THE THYROID GLAND
1. what is the colour of the normal thyroid gland ?
answer : brownish-red colour .
2. the thyroid gland is highly vascular. TRUE OR FALSE ?
answer : true .
3. which of the following statements about thyroid is true ?
a- thyroid is located anteriorly in the upper neck
b- thyroid is located posteriorly in the upper neck
c- thyroid is located anteriorly in the lower neck
d- thyroid is located posteriorly in the lower neck
answer : c . the thyroid is located anteriorly in the lower neck .
4. what is the vertical extension of the thyroid in relation to the vertebrae ?
a- C4 to T1
b- C5 to T1
c- C6 to T1
d- C3 to T1
answer : b . fifth cervical vertebra to the first thoracic vertebra . C5 to T1.
5. thyroid is ensheathed by a fascia . what is it ?
answer : pretracheal layer of the deep cervical fascia .
6. what are the number of lobes in thyroid ?
answer : 2 lobes . right and left lobes connected by a narrow, median isthmus .
7. what is the weight of the thyroid ?
answer : 25 g ( usually but can vary ) .
8. among men and women, who have heavier thyroids ?
answer : women have slightly heavier thyroids when compared to males.
9. a woman came to the doctor with complaints of increase in the size of thyroid during menstruation . if u were the doctor there, what would u do ?
answer : I would tell her that it is perfectly normal for the size of a woman’s thyroid to increase during menstruation .
10. a pregnant woman came to ur clinic with complaints of enlarged thyroid . what would you suggest ?
answer : I would tell her that there is nothing to worry , because it is absolutely normal for a woman’s thyroid to enlarge during pregnancy and menstruation .
11. how will you normally estimate the size of the thyroid gland ?
answer : by doing diagnostic ultrasound .
12. As I already told u women have heavier thyroids than men, hence the volume of thyroid in women is slightly more than in men. But there is a phase of life in both males and females where no significant difference between the volumes of the male and female thyroid was observed. When is that phase ?
answer : from 8 months to 15 years . between these ages the volumes of both male and female thyroid show no significant difference .
13. what is the shape of the lobes of the thyroid gland ?
answer : approximately conical .
14. the bases of the thyroid lobes are level with which tracheal cartilage ?
answer : 4th or 5th tracheal cartilages .
15. what is the length of each thyroid lobe ?
answer : 5cms long .
16. the posteromedial aspects of the thyroid lobes are attached to which structure ?
answer : cricoid cartilage .
17. what is the name of the ligament which attaches the lobes of thyroid to the cricoid cartilage posteromedially ?
answer : lateral thyroid ligament .
18. what is the part of the thyroid that connects the lower parts of the two lobes called ?
answer : isthmus .
19. what would you suggest to a healthy patient who has no isthmus ?
answer : I would suggest that it is physiologically normal for a person to be born without an isthmus and this happens occasionally . I would assure him that there is nothing to worry .
20. what is the length of the isthmus ?
answer : 1.25 cms transversely and vertically .
21. the isthmus normally lies anterior to which tracheal cartilages ?
answer : it usually lies anterior to second and third tracheal cartilages. ( it can lie slightly higher or slightly lower sometimes because of the variations in size and site of the thyroid gland )
22. what is the tumor marker of the medullary carcinoma of the thyroid?
answer : calcitonin .
23. what is the most common position of the thyroglossal cyst ?
answer : below the hyoid bone . ( check again ).
24. what is the name of the surgery done to treat the thyroglossal cyst/fistula ?
answer : sistrunk’s operation .
25. what is the hormone secreted by the thyroid that controls the calcium metabolism ?
answer : calcitonin .
26. superior thyroid artery is a branch of which artery ?
answer : external carotid artery .
( the branches of the external carotid artery are 1. superior thyroid artery 2.lingual artery 3.posterior auricular artery 4.facial artery 5.occipital artery 6.ascending pharyngeal artery 7.maxillary artery 8.superficial temporal artery ------ SLPFOAMS ------ SISTER LUCY’S POWDERED FACE OFTEN ATTRACTS MEDICAL STUDENTS . )
27. which is the only medial branch of the external carotid artery ?
answer : ascending pharyngeal artery . ( out of context but important .)
28. the thyroid develops from ?
a- ectoderm
b- mesoderm
c- dorsal pharyngeal gut endoderm
d- ventral pharyngeal gut endoderm
answer : d . ventral pharyngeal gut endoderm .
29. the development of thyroid occurs in which week of the intrauterine life ?
answer : 4th week .
30. what are the cells in the thyroid which produce the calcitonin ?
answer : C cells ( also called as the parafollicular cells .)
31. what is the function of calcitonin ?
answer : lowers blood calcium by inhibiting the bone resorption and inhibiting the calcium recovery from renal tubule ultrafiltrate .
32. the embryonic thyroid descends from a foramen located in the posterior part of the tongue . what is it ?
answer : it is called the foramen caecum .
33. the thyroid usually reaches the front of the trachea by the end of how many months of the intrauterine life ?
answer : by the end of 2nd month of intrauterine life .
34. the thyroglossal duct is originally a hollow tube running from foramen caecum to pharynx . TRUE OR FALSE ?
answer : true . ( check again )
35. thyroglossal duct tissue normally becomes solid and remains uncanalised after transit of the thyroid . TRUE OR FALSE ?
answer : FALSE ( check again )
36. the pyramidal lobe of the thyroid represents part of the thyroglossal duct . TRUE OR FALSE?
answer : TRUE ( check again ) .
37. most common histological type of thyroid cancer ?
answer : papillary carcinoma .
38. thyroid carcinoma with best prognosis ?
answer : papillary carcinoma .
39. screening method for medullary carcinoma of thyroid ?
a- serum calcitonin
b- serum calcium
c- serum ALP
d- serum acid phosphatase
answer : a . serum calcitonin .
40. the carcinoma of thyroid associated with hypocalcemia ?
answer : medullary carcinoma of thyroid . ( remember it secretes calcitonin ).
41. medullary carcinoma of thyroid arises from ?
a- parafollicular cells
b- cells lining the acini
c- capsule of thyroid
d- stroma of the gland
answer : a . parafollicular cells .
42. papillary carcinoma of thyroid usually presents as ?
answer : single nodule + local lymph node .
43. which of the following is/are used in the management of thyroid malignancy?
a- Iodine 131
b- Iodine 125
c- Technitium 99
d- Phosphorus 32
e- strontium
answer is a . Iodine 131 .
44. which of the following factors contribute to the development of duodenal ulcer ?
a- Iodine 131
b- Iodine 125
c- Technitium 99
d- Phosphorus 32
answer : a . iodine 131 .
45. characteristic eye sign in dysthyroid status ?
a- exopthalmos
b- ptosis
c- optic neuropathy
d- myopathy
answer : a . exopthalmos .
45. hurthle cells are seen in ?
a- hashimoto’s thyroiditis
b- follicular cell carcinoma
c- hurthle cell thyroid adenoma
d- all the above
answer is d . all the above .
46. the C cells of the thyroid parenchyma belongs to the APUD system of dispersed neuron-endocrine cells . what is APUD system ?
answer : AMINE PRECURSOR UPTAKE AND DECARBOXYLATION SYSTEM .
47. how did the C cells get their name ?
answer : C stands for Clear cells , because they have pale staining cytoplasm and hence appear clear .
48. what is arteria thyroidea ima ?
answer : an artery supplying thyroid which is seen occasionally and arises from the brachiocephalic trunk or aortic arch .
49. what are the two main arteries that supply the thyroid ?
answer : superior and inferior thyroid arteries . superior thyroid artery is a branch of the external carotid artery and the inferior thyroid artery is branch of the thyrocervical trunk .
50. C cells populate which part of the lateral lobe of the thyroid ?
a- upper one-third of the lateral lobe of thyroid
b- middle one-third of the lateral lobe of thyroid
c- lower one-third of the lateral lobe of the thyroid
d- distributed equally all over the lateral lobe of the thyroid
answer : b . C cells populate the middle one-third of the lateral lobe of the thyroid .
( typically found scattered within thyroid follicles , inside the basal lamina but not reaching the follicle lumen .)
51. pick out the correct statements .
a- the external laryngeal nerve runs close to the superior thyroid artery .
b- the recurrent laryngeal nerve runs close to the inferior thyroid artery .
c- the external laryngeal nerve runs close to the inferior thyroid artery .
d- the recurrent laryngeal nerve runs close to the superior thyroid artery .
answer : both a and b are correct . ( so the surgeon has to be very careful while ligating those arteries, while performing thyroidectomy ).
52. what are the branches of the thyrocervical trunk ?
answer : 1. inferior thyroid artery 2.suprascapular artery 3.transverse cervical artery ( also called transversalis artery colli ) .
53. thyrocervical trunk arises from which artery ?
answer : subclavian artery .
54. what are the active thyroid hormones secreted by the follicular epithelial
cells of the thyroid ?
answer: tri-iodothyronine T3 and tetra-iodothyronin T4 ( thyroxine ) .
55. treatment of medullary carcinoma of the thyroid with lymphnode metastasis?
a- subtotal thyroidectomy + radioiodine
b- subtotal thyroidectomy + radiotherapy
c- neartotal thyroidectomy + radioiodine
d- neartotal thyroidectomy + radiotherapy
e- total thyroidectomy + radiotherapy
answer : e . total thyroidectomy + radiotherapy .
56. what is near total thyroidectomy ?
a- right lobectomy + isthmusectomy
b- left lobectomy + isthmusectomy
c- bilateral lobectomy with isthmusectomy
d- right lobectomy + isthmusectomy + left half lobectomy
e- right and left lobectomy
answer : d .
57. papillary carcinoma of thyroid with bone metastasis is treated by?
a- subtotal thyroidectomy + radioiodine
b- subtotal thyroidectomy + radiotherapy
c- near total thyroidectomy + radioiodine
d- near total thyroidectomy + radiotherapy
e- total thyroidectomy + chemotherapy
answer : c and d . both . near total thyroidectomy with radioiodine and radiotherapy.
58. most common cause of thyroiditis is ?
a- hashimoto’s thyroiditis
b- reidl’s thyroiditis
c- subacute thyroiditis
d- viral thyroiditis
answer : a . hashimoto’s thyroiditis .
59. recurrent laryngeal nerve is in close association with ?
a- superior thyroid artery
b- inferior thyroid artery
c- middle thyroid vein
d- superior thyroid vein
answer : b . inferior thyroid artery .
60. thyroglossal cyst may occasionally give rise to which carcinoma ?
a- papillary
b- anaplastic
c- medullary
d- follicular
answer : a . papillary carcinoma of the thyroid .
61. a post-thyroidectomy patient develops signs and symptoms of tetany. The management is ?
a- I.V calcium gluconate
b- Bicarbonate
c- Calcitonin
d- Vitamin D
Answer : a . I.V calcium gluconate .
62. hypoparathyroidism following thyroid surgery occurs with in ?
a- 24 hours
b- 2-5 days
c- 7-14 days
d- 2-3 weeks
Answer : b . 2-5 days .
63. what are the normal levels of calcium in our body ?
answer : calcium,ionized - wholeblood – 1.1 to 1.4 mmol/litre – 4.5 to 5.6 mg/dl(meq/l) .
calcium - serum - 2.2 to 2.6 mmol/litre – 9 to 10.5 mg/dl(meq/l) .
64. a patient undergoes thyroid surgery following which he develops perioral tingling . his blood calcium is 8.9 meq/l. next step in the management is ?
a- vitamin D orally
b- oral calcium and vitamin D
c- intravenous calcium gluconate and serial monitoring
d- wait for calcium to decrease to less than 7 meq/l before taking further action
answer : b . oral calcium and vitamin D .
65. a patient after undergoing thyroid surgery presents with perioral paraesthesia . serum calcium level is 7 mg/dl . what will be the best management ?
a- oral vitamin D3
b- oral vitamin D3 and calcium
c- I.V calcium gluconate
d- Oral calcium
Answer : d . oral calcium .
66. which of the following is not a complication of total thyroidectomy ?
a- bleeding
b- airway obstruction
c- hoarseness
d- hypercalcemia
answer : d . hypercalcemia .
67. in post operative room after thyroid surgery , patient developed sudden respiratory distress , dressing was removed and it was found to be slightly blood stained and wound was bulging . what will be the first thing to be done ?
a- tracheostomy
b- cricothyroidectomy
c- laryngoscopy and intubation
d- remove the stitch and take the patient to O.T
answer : d . remove the stitch and take the patient to the O.T .
67. a patient presents with swelling in the neck following a thyroidectomy. What is the most likely resulting complication ?
a- respiratory obstruction
b- recurrent laryngeal nerve palsy
c- hypovolemia
d- hypocalcemia
answer : a . respiratory obstruction .
68. a patient presents with neck swelling and respiratory distress few hours after a thyroidectomy surgery. Next management would be ?
a- open immediately
b- tracheostomy
c- wait and watch
d- oxygen by mask
answer : a . open immediately .
69. after thyroidectomy patient developed stridor within 2 hours. All are likely causes of stridor except ?
a- hypocalcemia
b- recurrent laryngeal nerve palsy
c- laryngomalacia
d- wound hematoma
answer : a . hypocalcemia due to hypoparathyroidism after thyroid surgey normall results with in 2-5 days .
70. which of the following will not lead to respiratory distress after thyroid surgery?
a- laryngomalacia
b- bilateral recurrent laryngeal nerve palsy
c- hypocalcemia
d- none
answer : d . none . all the 3 can lead to respiratory distress .
71. how does hypocalcemia result in respiratory distress ?
answer : pending .
72. papillary carcinoma of the thyroid ( PCT ) patients are ?
a- euthyroid
b- hypothyroid
c- hyperthyroid
d- T3 thyrotoxicosis
Answer : a . euthyroid .
73. medullary carcinoma of thyroid is derived from which cells ?
a- follicular
b- para follicular
c- oxyphilic
d- lymphocytes
answer : para follicular cells ( also called C cells ) .
74. HURTHLE cell carcinomas are derived from which cells ?
a- follicular cells
b- para follicular cells
c- oxyphilic cells
d- lymphocytes
answer : c . oxyphilic cells .
75. patients with MEN 2a also may have hirschsprung’s and lichen cutaneous amyloidosis ? TRUE OR FALSE ?
answer : true .
76. the malignancy which is common on long standing goiter ?
a- PCT
b- MCT
c- FCT
d- Anaplastic
Answer : c . Follicular carcinoma of the thyroid .
77. cancer common in iodine deficient areas ?
a- papillary
b- medullary
c- anaplastic
d- follicular
answer : c and d . follicular and anaplastic both are common .
78. least malignant thyroid cancer ?
e- papillary
f- medullary
g- anaplastic
h- follicular
answer : e . papillary .
79. commonest tumor of the thyroid ?
answer : papillary carcinoma of the thyroid .
80. which of the following gene defects is associated with development of the medullary carcinoma of the thyroid ?
a- RET proto oncogene
b- FAP gene
c- RB gene
d- BRCA 1 gene
Answer : a . RET proto oncogene .
81. what are the other diseases associated with the RET gene ?
answer : medullary thyroid carcinoma, hirschsprung’s disease and pheochromocytoma.
82. RET proto-oncogene encodes for ?
a- tyrosine kinase receptor on the cytoplasmic membrane
b- protein kinase
c- IP3
d- All the above
Answer : a . tyrosine kinase receptor on the cytoplasmic membrane .
83. RET gene is located on which chromosome ?
Answer : 10 th chromosome .
84. rearrangement of RET gene leads to ?
a- PTC
b- MTC
c- FCT
d- Lymphoma
Answer : a. papillary thyroid cancer .
85. gene implicated in papillary thyroid cancer is ?
a- RET
b- K ras
c- C myc
d- APC
Answer : a . RET gene .
86. point mutation of RET gene leads to ?
answer : familial medullary carcinoma ( MEN 2A AND MEN 2B ).
87. RET ligand is identified as ?
Answer: GDNF ( glial cell line-derived neurotropic factor ).
88. psammoma bodies are seen in all of the following conditions except ?
a- serous cystadenoma of ovary
b- papillary carcinoma of thyroid
c- meningioma
d- mucinous cystadenoma of ovary
answer : d .
89. all of the following are early life threatening complications of thyroid operation except ?
a- tracheomalacia and collapse of larynx
b- wound hematoma with compression of the trachea
c- hypocalcemia
d- thyroid storm
answer : c . hypocalcemia .
90. in pregnancy ?
a- thiouracil is contraindicated
b- surgery is contraindicated
c- radioiodine is contraindicated
d- none
answer: c . only radioiodine is contraindicated .
91. amyloid stroma is seen in which carcinoma of thyroid?
Answer : medullary carcinoma of thyroid .
92. lateral aberrant thyroid refers to ?
a- congenital thyroid abnormality
b- metastatic foci from primary in the thyroid
c- struma ovarii
d- lingual thyroid
answer : b . metastatic foci from primary carcinoma in the thyroid .
93. a patient with long standing multinodular goiter develops hoarseness of voice ; also the swelling undergoes sudden increase in size. Likely diagnosis is ?
answer : follicular carcinoma of thyroid .
94. a patient has pituitary tumor and pheochromocytoma and a thyroid nodule . which carcinoma is most likely to occur ?
answer : medullary carcinoma of the thyroid . the condition is MEN 2a or MEN 2b. MEN 1 comprises of parathyroid , pituitary and pancreatic tumors. MEN 2a comprises of parathyroid, medullary carcinoma of thyroid and pheochromocytoma tumors. MEN 2b comprises of medullary carcinoma of thyroid, pheochromocytoma and neuromas .
95. a patient presented with headache and flushing . he has a family history of his relative having died of a thyroid tumor. The investigation that would be required for this patient will be ?
a- chest x-ray
b- measurement of 5-HIAA
c- measurement of catecholamine
d- intravenous pyelography
answer : c . measurement of catecholamines . headache and flushing suggest symptoms of adrenal tumor and a history of thyroid tumor in the relative suggest the MEN syndrome type 2a or 2b . so the adrenal tumor is probably pheochromocytoma and so catecholamines have to be measured .
96. cancer that develops after irradiation ?
a- PCT
b- MCT
c- FCT
d- Anaplastic
Answer : papillary carcinoma of the thyroid .
97. what is an oncogene ?
answer : gene that contributes directly to tumor genesis .
98. mutated p53 gene is formed in most of ?
a- anaplastic carcinomas
b- PCT
c- MCT
d- FCT
Answer : a . anaplastic carcinomas .
99. deletion of which chromosome accompanies transformation of follicular adenoma to follicular adeno carcinoma ?
answer : 3p .
100. treatment of choice for medullary carcinoma of thyroid is ?
a- total thyroidectomy
b- partial thyroidectomy
c- iodine 131 ablation
d- hemithyroidectomy
answer : a . total thyroidectomy .
Tuesday, April 29, 2008
Wednesday, April 23, 2008
113 - connective tissue diseases mcqs part 2
- which of the following antibodies are most specific for SLE ?
a- anti dS-DNA
b- anti SS DNA
c- anti histone
d- anti Ro
answer is a . anti dS-DNA .
- anti nuclear antibodies are seen in all except ?
a- SLE
b- Systemic sclerosis
c- Morphea
d- Pemphigus vulgaris
Answer is d. pemphigus vulgaris is not characterized by anti-nuclear antibodies .
- keratoderma blenorrhagica is pathognomonic of ?
a- behcet’s disease
b- reiter’s disease
c- lyme’s disease
d- glucaganoma
answer is b . reiter’s disease .
- small vessels are involved in ?
a- takayasu arteritis
b-
c- PAN
d- Temporal arteritis
Answer is c . PAN .
- commonest cardiac lesion in rheumatoid arthritis ?
a- pancarditis
b- pericarditis
c- myocarditis
d- endocarditis
answer is b . pericarditis .
112 - connective tissue disorders mcqs
1. martel’s sign is seen in ?
a- rheumatoid arthritis
b- ankylosing spondylitis
c- gout
d- osteoarthritis
answer is c . martel’s sign is seen in gout .
2. onion skin spleen is seen in ?
a- ITP
b- Thalassemia
c- SLE
d- Scleroderma
Answer is c . SLE .
3. heberden’s nodes are seen in ?
a- rheumatoid arthritis
b- rheumatic arthritis
c- osteoarthritis
d- SLE
Answer is c . osteoarthritis .
4. lupus pernio is ?
a- sarcoidosis
b- skin TB
c- SLE complication
d- DLE and SLE
Answer is a . lupus pernio is sarcoidosis .
5. anti-topoisomerase 1 is a marker of ?
a- systemic sclerosis
b- classic polyarteritis nodosa
c- nephrotic syndrome
d- rheumatoid arthritis
answer is a. systemic sclerosis .
a- rheumatoid arthritis
b- ankylosing spondylitis
c- gout
d- osteoarthritis
answer is c . martel’s sign is seen in gout .
2. onion skin spleen is seen in ?
a- ITP
b- Thalassemia
c- SLE
d- Scleroderma
Answer is c . SLE .
3. heberden’s nodes are seen in ?
a- rheumatoid arthritis
b- rheumatic arthritis
c- osteoarthritis
d- SLE
Answer is c . osteoarthritis .
4. lupus pernio is ?
a- sarcoidosis
b- skin TB
c- SLE complication
d- DLE and SLE
Answer is a . lupus pernio is sarcoidosis .
5. anti-topoisomerase 1 is a marker of ?
a- systemic sclerosis
b- classic polyarteritis nodosa
c- nephrotic syndrome
d- rheumatoid arthritis
answer is a. systemic sclerosis .
Friday, April 18, 2008
111 - nervous system mcqs - part 5
17 . a woman complains of headache associated with paresthesias of the right upper and lower limb : likely diagnosis ?
a- trigeminal neuralgia
b- glossopharyngeal neuralgia
c- migraine
d- cluster headache
answer is c .
18 . opthalmoplegic migraine means :
a- when headache is followed by complete paralysis of the third and sixth nerve on the same side as the hemicrania
b- when the headache is followed by partial paralysis of the third nerve on the same side as the hemicrania without any scotoma .
c- headache associated with third ,fourth and sixth nerve paralysis
d- headache associated with optic neuritis
answer is b .
19 . a woman has bilateral headache that worsens with emotional stress, she has two children , both doing badly in school, diagnosis is ?
a- migraine
b- cluster headache
c- tension headache
d- trigeminal neuralgia
answer is c . tension headache .
20 . a 64 year old lady kamla complains of severe unilateral headache on the right side and blindness for 2 days . on examination there is a thick cord like structure on the lateral side of the head . the ESR is 80 mm/hr in the first hour . the most likely diagnosis is ?
a- temporal arteritis
b- migraine
c- cluster headache
d- sinusitis
answer is a . temporal arteritis .
a- trigeminal neuralgia
b- glossopharyngeal neuralgia
c- migraine
d- cluster headache
answer is c .
18 . opthalmoplegic migraine means :
a- when headache is followed by complete paralysis of the third and sixth nerve on the same side as the hemicrania
b- when the headache is followed by partial paralysis of the third nerve on the same side as the hemicrania without any scotoma .
c- headache associated with third ,fourth and sixth nerve paralysis
d- headache associated with optic neuritis
answer is b .
19 . a woman has bilateral headache that worsens with emotional stress, she has two children , both doing badly in school, diagnosis is ?
a- migraine
b- cluster headache
c- tension headache
d- trigeminal neuralgia
answer is c . tension headache .
20 . a 64 year old lady kamla complains of severe unilateral headache on the right side and blindness for 2 days . on examination there is a thick cord like structure on the lateral side of the head . the ESR is 80 mm/hr in the first hour . the most likely diagnosis is ?
a- temporal arteritis
b- migraine
c- cluster headache
d- sinusitis
answer is a . temporal arteritis .
110 - nervous system mcqs - part 4
13 . a 45 year old man presents with a daily head ache . he describes two attacks per day , over the past three years . each attack lasts about an hour and awakens the patient from sleep .the patient has noted associated tearing and reddening of his right eye as well as nasal stuffiness. The pain is deep, excruciating and limited to the right side of the head . the neurological examination is non focal . the most likely diagnosis of this patient’s headache is ?
a- migraine headache
b- cluster headache
c- tension headache
d- brain tumor
answer is b. cluster headache .
14 . cluster headache is characterized by , all except ?
a- affects predominantly females
b- unilateral headache
c- onset typically in 20-50 years of life
d- associated with conjunctival congestion
answer is a . affects predominantly females . cluster headache predominantly affects males . males are 7- 8 times more commonly affected than women .
15 - a female has episodic , recurrent headache in left hemicranium with nausea and parasthesia on right upper and lower limbs, he is most probably suffering from ?
a- migraine
b- glossopharyngeal neuralgia
c- herpes zoster infection of the trigeminal neuralgia
d- brain tumor
answer is a . migraine .
16 - a female aged 30, presents with episodic throbbing headache for past 4 years . it usually involves one half of the face and is associated with nausea and vomiting. There is no aura . most likely diagnosis is ?
a. migraine
b. cluster headache
c. angle closure glaucoma
d. temporal arteritis
answer is a . migraine .
a- migraine headache
b- cluster headache
c- tension headache
d- brain tumor
answer is b. cluster headache .
14 . cluster headache is characterized by , all except ?
a- affects predominantly females
b- unilateral headache
c- onset typically in 20-50 years of life
d- associated with conjunctival congestion
answer is a . affects predominantly females . cluster headache predominantly affects males . males are 7- 8 times more commonly affected than women .
15 - a female has episodic , recurrent headache in left hemicranium with nausea and parasthesia on right upper and lower limbs, he is most probably suffering from ?
a- migraine
b- glossopharyngeal neuralgia
c- herpes zoster infection of the trigeminal neuralgia
d- brain tumor
answer is a . migraine .
16 - a female aged 30, presents with episodic throbbing headache for past 4 years . it usually involves one half of the face and is associated with nausea and vomiting. There is no aura . most likely diagnosis is ?
a. migraine
b. cluster headache
c. angle closure glaucoma
d. temporal arteritis
answer is a . migraine .
109 - cluster headache case presentation mcq
a 45 year old man presents with a daily head ache . he describes two attacks per day , over the past three years . each attack lasts about an hour and awakens the patient from sleep .the patient has noted associated tearing and reddening of his right eye as well as nasal stuffiness. The pain is deep, excruciating and limited to the right side of the head . the neurological examination is non focal . the most likely diagnosis of this patient’s headache is ?
a- migraine headache
b- cluster headache
c- tension headache
d- brain tumor
answer is b. cluster headache .
a- migraine headache
b- cluster headache
c- tension headache
d- brain tumor
answer is b. cluster headache .
108 - nervous system mcqs - part 3
9 . following sensory impairments occur in extensive damage to primary somatosensory area of cerebral cortex , except :
a- pressure
b- sensory localization
c- exact weight determination
d- pain
answer is d . pain .
10 . lesion in which of the following structure leads to kluver-bucy syndrome?
a- amygdala
b- hippocampus
c- temporal lobe
d- hypothalamus
answer is a . this syndrome is characterized by excessive sex drive ,eating non edible things etc . experimentally observed in monkeys .
11 . extra pyramidal symptoms are seen in all except ?
a- paralysis agitans
b- carbonmonoxide poisoning
c- cerebrovascular accident
d- multiple sclerosis
answer is d . multiple sclerosis .
12 . what test is not useful in a patient with history of syncopal attacks ?
a- electrophysiological testing
b- tilt table testing
c- PET scan
d- Holter monitoring
Answer is c . PET scan .
a- pressure
b- sensory localization
c- exact weight determination
d- pain
answer is d . pain .
10 . lesion in which of the following structure leads to kluver-bucy syndrome?
a- amygdala
b- hippocampus
c- temporal lobe
d- hypothalamus
answer is a . this syndrome is characterized by excessive sex drive ,eating non edible things etc . experimentally observed in monkeys .
11 . extra pyramidal symptoms are seen in all except ?
a- paralysis agitans
b- carbonmonoxide poisoning
c- cerebrovascular accident
d- multiple sclerosis
answer is d . multiple sclerosis .
12 . what test is not useful in a patient with history of syncopal attacks ?
a- electrophysiological testing
b- tilt table testing
c- PET scan
d- Holter monitoring
Answer is c . PET scan .
107 - nervous system mcqs - part 2
5 . spinal segment in knee jerk include all of the following except ?
a- L1
b- L2
c- L3
d- L4
Answer is L1 .
6 . all of the following are features of pseudotumor cerebri except ?
a- normal sized ventricles on CT scan
b- increased protein in CSF
c- papilledema
d- absence of focal neurological deficit
answer is b. increased protein in CSF .
7 . prosapagnosia is characterized by ?
a- inability to read
b- inability to identify faces
c- inability to write
d- inability to speak
answer is b . inability to identify faces .
8 . which of the following is false about pseudotumor cerebri?
a- increased intracranial tension
b- convulsions
c- papilledema
d- normal CT scan
answer is b . convulsions are not a feature of pseudotumor cerebri .
a- L1
b- L2
c- L3
d- L4
Answer is L1 .
6 . all of the following are features of pseudotumor cerebri except ?
a- normal sized ventricles on CT scan
b- increased protein in CSF
c- papilledema
d- absence of focal neurological deficit
answer is b. increased protein in CSF .
7 . prosapagnosia is characterized by ?
a- inability to read
b- inability to identify faces
c- inability to write
d- inability to speak
answer is b . inability to identify faces .
8 . which of the following is false about pseudotumor cerebri?
a- increased intracranial tension
b- convulsions
c- papilledema
d- normal CT scan
answer is b . convulsions are not a feature of pseudotumor cerebri .
106 - nervous system mcqs - part 1
1 . UMN lesion is characterized by :
a- weakness and spasticity
b- fasciculations
c- rigidity
d- localized muscular atrophy
answer is a .
2 . which of the following signs is not suggestive of a cervical spinal
cord iinjury ?
a- Flaccidity
b- increased rectal sphincter tone
c- diaphragmatic breathing
d- priapism
answer is b . the cervical spinal cord injury is characterized by decreased rectal sphincter tone and not increased rectal sphincter tone.
3 . with which one of the following, Lower motor neuron lesions are associated ?
a- flaccid paralysis
b- hyperactive stretch reflex
c- spasticity
d- muscular inco-ordination.
Answer is a . flaccid paralysis .
4 . all the following are features of cerebellar disease ?
a- intention tremors
b- past pointing
c- hypertonia
d- ataxia
answer is c . hypertonia .
a- weakness and spasticity
b- fasciculations
c- rigidity
d- localized muscular atrophy
answer is a .
2 . which of the following signs is not suggestive of a cervical spinal
cord iinjury ?
a- Flaccidity
b- increased rectal sphincter tone
c- diaphragmatic breathing
d- priapism
answer is b . the cervical spinal cord injury is characterized by decreased rectal sphincter tone and not increased rectal sphincter tone.
3 . with which one of the following, Lower motor neuron lesions are associated ?
a- flaccid paralysis
b- hyperactive stretch reflex
c- spasticity
d- muscular inco-ordination.
Answer is a . flaccid paralysis .
4 . all the following are features of cerebellar disease ?
a- intention tremors
b- past pointing
c- hypertonia
d- ataxia
answer is c . hypertonia .
Monday, April 14, 2008
105 - guillian-barre syndrome
What is Guillain-Barré syndrome?
Guillain-Barré syndrome is a disorder in which the body's immune system attacks part of the peripheral nervous system. The first symptoms of this disorder include varying degrees of weakness or tingling sensations in the legs. In many instances the weakness and abnormal sensations spread to the arms and upper body. These symptoms can increase in intensity until certain muscles cannot be used at all and, when severe, the patient is almost totally paralyzed. In these cases the disorder is life threatening - potentially interfering with breathing and, at times, with blood pressure or heart rate - and is considered a medical emergency. Such a patient is often put on a respirator to assist with breathing and is watched closely for problems such as an abnormal heart beat, infections, blood clots, and high or low blood pressure. Most patients, however, recover from even the most severe cases of Guillain-Barré syndrome, although some continue to have a certain degree of weakness.
Guillain-Barré syndrome can affect anybody. It can strike at any age and both sexes are equally prone to the disorder. The syndrome is rare, however, afflicting only about one person in 100,000. Usually Guillain-Barré occurs a few days or weeks after the patient has had symptoms of a respiratory or gastrointestinal viral infection. Occasionally surgery or vaccinations will trigger the syndrome.
After the first clinical manifestations of the disease, the symptoms can progress over the course of hours, days, or weeks. Most people reach the stage of greatest weakness within the first 2 weeks after symptoms appear, and by the third week of the illness 90 percent of all patients are at their weakest.
What causes Guillain-Barré syndrome?
No one yet knows why Guillain-Barré—which is not contagious—strikes some people and not others. Nor does anyone know exactly what sets the disease in motion.
What scientists do know is that the body's immune system begins to attack the body itself, causing what is known as an autoimmune disease. Usually the cells of the immune system attack only foreign material and invading organisms. In Guillain-Barré syndrome, however, the immune system starts to destroy the myelin sheath that surrounds the axons of many peripheral nerves, or even the axons themselves (axons are long, thin extensions of the nerve cells; they carry nerve signals). The myelin sheath surrounding the axon speeds up the transmission of nerve signals and allows the transmission of signals over long distances.
In diseases in which the peripheral nerves' myelin sheaths are injured or degraded, the nerves cannot transmit signals efficiently. That is why the muscles begin to lose their ability to respond to the brain's commands, commands that must be carried through the nerve network. The brain also receives fewer sensory signals from the rest of the body, resulting in an inability to feel textures, heat, pain, and other sensations. Alternately, the brain may receive inappropriate signals that result in tingling, "crawling-skin," or painful sensations. Because the signals to and from the arms and legs must travel the longest distances they are most vulnerable to interruption. Therefore, muscle weakness and tingling sensations usually first appear in the hands and feet and progress upwards.
When Guillain-Barré is preceded by a viral or bacterial infection, it is possible that the virus has changed the nature of cells in the nervous system so that the immune system treats them as foreign cells. It is also possible that the virus makes the immune system itself less discriminating about what cells it recognizes as its own, allowing some of the immune cells, such as certain kinds of lymphocytes and macrophages, to attack the myelin. Sensitized T lymphocytes cooperate with B lymphocytes to produce antibodies against components of the myelin sheath and may contribute to destruction of the myelin. Scientists are investigating these and other possibilities to find why the immune system goes awry in Guillain-Barré syndrome and other autoimmune diseases. The cause and course of Guillain-Barré syndrome is an active area of neurological investigation, incorporating the cooperative efforts of neurological scientists, immunologists, and virologists.
How is Guillain-Barré syndrome diagnosed?
Guillain-Barré is called a syndrome rather than a disease because it is not clear that a specific disease-causing agent is involved. A syndrome is a medical condition characterized by a collection of symptoms (what the patient feels) and signs (what a doctor can observe or measure). The signs and symptoms of the syndrome can be quite varied, so doctors may, on rare occasions, find it difficult to diagnose Guillain-Barré in its earliest stages.
Several disorders have symptoms similar to those found in Guillain-Barré, so doctors examine and question patients carefully before making a diagnosis. Collectively, the signs and symptoms form a certain pattern that helps doctors differentiate Guillain-Barré from other disorders. For example, physicians will note whether the symptoms appear on both sides of the body (most common in Guillain-Barré) and the quickness with which the symptoms appear (in other disorders, muscle weakness may progress over months rather than days or weeks). In Guillain-Barré, reflexes such as knee jerks are usually lost. Because the signals traveling along the nerve are slower, a nerve conduction velocity (NCV) test can give a doctor clues to aid the diagnosis. In Guillain-Barré patients, the cerebrospinal fluid that bathes the spinal cord and brain contains more protein than usual. Therefore a physician may decide to perform a spinal tap, a procedure in which the doctor inserts a needle into the patient's lower back to draw cerebrospinal fluid from the spinal column.
How is Guillain-Barré treated?
There is no known cure for Guillain-Barré syndrome. However, there are therapies that lessen the severity of the illness and accelerate the recovery in most patients. There are also a number of ways to treat the complications of the disease.
Currently, plasma exchange (sometimes called plasmapheresis) and high-dose immunoglobulin therapy are used. Both of them are equally effective, but immunoglobulin is easier to administer. Plasma exchange is a method by which whole blood is removed from the body and processed so that the red and white blood cells are separated from the plasma, or liquid portion of the blood. The blood cells are then returned to the patient without the plasma, which the body quickly replaces. Scientists still don't know exactly why plasma exchange works, but the technique seems to reduce the severity and duration of the Guillain-Barré episode. This may be because the plasma portion of the blood contains elements of the immune system that may be toxic to the myelin.
In high-dose immunoglobulin therapy, doctors give intravenous injections of the proteins that, in small quantities, the immune system uses naturally to attack invading organisms. Investigators have found that giving high doses of these immunoglobulins, derived from a pool of thousands of normal donors, to Guillain-Barré patients can lessen the immune attack on the nervous system. Investigators don't know why or how this works, although several hypotheses have been proposed.
The use of steroid hormones has also been tried as a way to reduce the severity of Guillain-Barré, but controlled clinical trials have demonstrated that this treatment not only is not effective but may even have a deleterious effect on the disease.
The most critical part of the treatment for this syndrome consists of keeping the patient's body functioning during recovery of the nervous system. This can sometimes require placing the patient on a respirator, a heart monitor, or other machines that assist body function. The need for this sophisticated machinery is one reason why Guillain-Barré syndrome patients are usually treated in hospitals, often in an intensive care ward. In the hospital, doctors can also look for and treat the many problems that can afflict any paralyzed patient - complications such as pneumonia or bed sores.
Often, even before recovery begins, caregivers may be instructed to manually move the patient's limbs to help keep the muscles flexible and strong. Later, as the patient begins to recover limb control, physical therapy begins. Carefully planned clinical trials of new and experimental therapies are the key to improving the treatment of patients with Guillain-Barré syndrome. Such clinical trials begin with the research of basic and clinical scientists who, working with clinicians, identify new approaches to treating patients with the disease.
What is the long-term outlook for those with Guillain-Barré syndrome?
Guillain-Barré syndrome can be a devastating disorder because of its sudden and unexpected onset. In addition, recovery is not necessarily quick. As noted above, patients usually reach the point of greatest weakness or paralysis days or weeks after the first symptoms occur. Symptoms then stabilize at this level for a period of days, weeks, or, sometimes, months. The recovery period may be as little as a few weeks or as long as a few years. About 30 percent of those with Guillain-Barré still have a residual weakness after 3 years. About 3 percent may suffer a relapse of muscle weakness and tingling sensations many years after the initial attack.
Guillain-Barré syndrome patients face not only physical difficulties, but emotionally painful periods as well. It is often extremely difficult for patients to adjust to sudden paralysis and dependence on others for help with routine daily activities. Patients sometimes need psychological counseling to help them adapt.
What research is being done?
Scientists are concentrating on finding new treatments and refining existing ones. Scientists are also looking at the workings of the immune system to find which cells are responsible for beginning and carrying out the attack on the nervous system. The fact that so many cases of Guillain-Barré begin after a viral or bacterial infection suggests that certain characteristics of some viruses and bacteria may activate the immune system inappropriately. Investigators are searching for those characteristics. Certain proteins or peptides in viruses and bacteria may be the same as those found in myelin, and the generation of antibodies to neutralize the invading viruses or bacteria could trigger the attack on the myelin sheath. As noted previously, neurological scientists, immunologists, virologists, and pharmacologists are all working collaboratively to learn how to prevent this disorder and to make better therapies available when it strikes.
Guillain-Barré syndrome is a disorder in which the body's immune system attacks part of the peripheral nervous system. The first symptoms of this disorder include varying degrees of weakness or tingling sensations in the legs. In many instances the weakness and abnormal sensations spread to the arms and upper body. These symptoms can increase in intensity until certain muscles cannot be used at all and, when severe, the patient is almost totally paralyzed. In these cases the disorder is life threatening - potentially interfering with breathing and, at times, with blood pressure or heart rate - and is considered a medical emergency. Such a patient is often put on a respirator to assist with breathing and is watched closely for problems such as an abnormal heart beat, infections, blood clots, and high or low blood pressure. Most patients, however, recover from even the most severe cases of Guillain-Barré syndrome, although some continue to have a certain degree of weakness.
Guillain-Barré syndrome can affect anybody. It can strike at any age and both sexes are equally prone to the disorder. The syndrome is rare, however, afflicting only about one person in 100,000. Usually Guillain-Barré occurs a few days or weeks after the patient has had symptoms of a respiratory or gastrointestinal viral infection. Occasionally surgery or vaccinations will trigger the syndrome.
After the first clinical manifestations of the disease, the symptoms can progress over the course of hours, days, or weeks. Most people reach the stage of greatest weakness within the first 2 weeks after symptoms appear, and by the third week of the illness 90 percent of all patients are at their weakest.
What causes Guillain-Barré syndrome?
No one yet knows why Guillain-Barré—which is not contagious—strikes some people and not others. Nor does anyone know exactly what sets the disease in motion.
What scientists do know is that the body's immune system begins to attack the body itself, causing what is known as an autoimmune disease. Usually the cells of the immune system attack only foreign material and invading organisms. In Guillain-Barré syndrome, however, the immune system starts to destroy the myelin sheath that surrounds the axons of many peripheral nerves, or even the axons themselves (axons are long, thin extensions of the nerve cells; they carry nerve signals). The myelin sheath surrounding the axon speeds up the transmission of nerve signals and allows the transmission of signals over long distances.
In diseases in which the peripheral nerves' myelin sheaths are injured or degraded, the nerves cannot transmit signals efficiently. That is why the muscles begin to lose their ability to respond to the brain's commands, commands that must be carried through the nerve network. The brain also receives fewer sensory signals from the rest of the body, resulting in an inability to feel textures, heat, pain, and other sensations. Alternately, the brain may receive inappropriate signals that result in tingling, "crawling-skin," or painful sensations. Because the signals to and from the arms and legs must travel the longest distances they are most vulnerable to interruption. Therefore, muscle weakness and tingling sensations usually first appear in the hands and feet and progress upwards.
When Guillain-Barré is preceded by a viral or bacterial infection, it is possible that the virus has changed the nature of cells in the nervous system so that the immune system treats them as foreign cells. It is also possible that the virus makes the immune system itself less discriminating about what cells it recognizes as its own, allowing some of the immune cells, such as certain kinds of lymphocytes and macrophages, to attack the myelin. Sensitized T lymphocytes cooperate with B lymphocytes to produce antibodies against components of the myelin sheath and may contribute to destruction of the myelin. Scientists are investigating these and other possibilities to find why the immune system goes awry in Guillain-Barré syndrome and other autoimmune diseases. The cause and course of Guillain-Barré syndrome is an active area of neurological investigation, incorporating the cooperative efforts of neurological scientists, immunologists, and virologists.
How is Guillain-Barré syndrome diagnosed?
Guillain-Barré is called a syndrome rather than a disease because it is not clear that a specific disease-causing agent is involved. A syndrome is a medical condition characterized by a collection of symptoms (what the patient feels) and signs (what a doctor can observe or measure). The signs and symptoms of the syndrome can be quite varied, so doctors may, on rare occasions, find it difficult to diagnose Guillain-Barré in its earliest stages.
Several disorders have symptoms similar to those found in Guillain-Barré, so doctors examine and question patients carefully before making a diagnosis. Collectively, the signs and symptoms form a certain pattern that helps doctors differentiate Guillain-Barré from other disorders. For example, physicians will note whether the symptoms appear on both sides of the body (most common in Guillain-Barré) and the quickness with which the symptoms appear (in other disorders, muscle weakness may progress over months rather than days or weeks). In Guillain-Barré, reflexes such as knee jerks are usually lost. Because the signals traveling along the nerve are slower, a nerve conduction velocity (NCV) test can give a doctor clues to aid the diagnosis. In Guillain-Barré patients, the cerebrospinal fluid that bathes the spinal cord and brain contains more protein than usual. Therefore a physician may decide to perform a spinal tap, a procedure in which the doctor inserts a needle into the patient's lower back to draw cerebrospinal fluid from the spinal column.
How is Guillain-Barré treated?
There is no known cure for Guillain-Barré syndrome. However, there are therapies that lessen the severity of the illness and accelerate the recovery in most patients. There are also a number of ways to treat the complications of the disease.
Currently, plasma exchange (sometimes called plasmapheresis) and high-dose immunoglobulin therapy are used. Both of them are equally effective, but immunoglobulin is easier to administer. Plasma exchange is a method by which whole blood is removed from the body and processed so that the red and white blood cells are separated from the plasma, or liquid portion of the blood. The blood cells are then returned to the patient without the plasma, which the body quickly replaces. Scientists still don't know exactly why plasma exchange works, but the technique seems to reduce the severity and duration of the Guillain-Barré episode. This may be because the plasma portion of the blood contains elements of the immune system that may be toxic to the myelin.
In high-dose immunoglobulin therapy, doctors give intravenous injections of the proteins that, in small quantities, the immune system uses naturally to attack invading organisms. Investigators have found that giving high doses of these immunoglobulins, derived from a pool of thousands of normal donors, to Guillain-Barré patients can lessen the immune attack on the nervous system. Investigators don't know why or how this works, although several hypotheses have been proposed.
The use of steroid hormones has also been tried as a way to reduce the severity of Guillain-Barré, but controlled clinical trials have demonstrated that this treatment not only is not effective but may even have a deleterious effect on the disease.
The most critical part of the treatment for this syndrome consists of keeping the patient's body functioning during recovery of the nervous system. This can sometimes require placing the patient on a respirator, a heart monitor, or other machines that assist body function. The need for this sophisticated machinery is one reason why Guillain-Barré syndrome patients are usually treated in hospitals, often in an intensive care ward. In the hospital, doctors can also look for and treat the many problems that can afflict any paralyzed patient - complications such as pneumonia or bed sores.
Often, even before recovery begins, caregivers may be instructed to manually move the patient's limbs to help keep the muscles flexible and strong. Later, as the patient begins to recover limb control, physical therapy begins. Carefully planned clinical trials of new and experimental therapies are the key to improving the treatment of patients with Guillain-Barré syndrome. Such clinical trials begin with the research of basic and clinical scientists who, working with clinicians, identify new approaches to treating patients with the disease.
What is the long-term outlook for those with Guillain-Barré syndrome?
Guillain-Barré syndrome can be a devastating disorder because of its sudden and unexpected onset. In addition, recovery is not necessarily quick. As noted above, patients usually reach the point of greatest weakness or paralysis days or weeks after the first symptoms occur. Symptoms then stabilize at this level for a period of days, weeks, or, sometimes, months. The recovery period may be as little as a few weeks or as long as a few years. About 30 percent of those with Guillain-Barré still have a residual weakness after 3 years. About 3 percent may suffer a relapse of muscle weakness and tingling sensations many years after the initial attack.
Guillain-Barré syndrome patients face not only physical difficulties, but emotionally painful periods as well. It is often extremely difficult for patients to adjust to sudden paralysis and dependence on others for help with routine daily activities. Patients sometimes need psychological counseling to help them adapt.
What research is being done?
Scientists are concentrating on finding new treatments and refining existing ones. Scientists are also looking at the workings of the immune system to find which cells are responsible for beginning and carrying out the attack on the nervous system. The fact that so many cases of Guillain-Barré begin after a viral or bacterial infection suggests that certain characteristics of some viruses and bacteria may activate the immune system inappropriately. Investigators are searching for those characteristics. Certain proteins or peptides in viruses and bacteria may be the same as those found in myelin, and the generation of antibodies to neutralize the invading viruses or bacteria could trigger the attack on the myelin sheath. As noted previously, neurological scientists, immunologists, virologists, and pharmacologists are all working collaboratively to learn how to prevent this disorder and to make better therapies available when it strikes.
104 - duchenne muscular dystrophy ( DMD )
Alternative Names
Pseudohypertrophic muscular dystrophy; Muscular dystrophy - Duchenne type
Definition
Duchenne muscular dystrophy is an inherited disorder, characterized by rapidly-worsening muscle weakness that starts in the legs and pelvis, and later affects the whole body.
Causes
Duchenne muscular dystrophy is a rapidly-worsening form of muscular dystrophy. It is caused by a defective gene for dystrophin (a protein in the muscles). However, it often occurs in people without a known family history of the condition. This disorder is marked by worsening loss of muscle function, which begins in the lower limbs.
Duchenne muscular dystrophy is inherited in what is known as an X-linked recessive pattern. The defective gene is found on the X chromosome. Because women have two X chromosomes, if one contains a normal copy of the gene, that gene will make enough of the protein to prevent symptoms. But boys have an X chromosome from their mother and a Y from father, so if the X chromosome is defective, there is no second X to make up for it and they will develop the disease.
The sons of carrier females (women with one defective chromosome but no symptoms themselves) each have a 50% chance of having the disease, and the daughters each have a 50% chance of being carriers.
Symptoms usually appear before age 6 and may appear as early as infancy. There is progressive muscle weakness of the legs and pelvis, which is associated with a loss of muscle mass (wasting). Muscle weakness also occurs in the arms, neck, and other areas, but not as severely or as early as in the lower half of the body.
Calf muscles initially grow larger -- the enlarged muscle tissue is eventually replaced by fat and connective tissue (a condition called pseudohypertrophy). Muscle contractures occur in the legs. Thus, the muscles are unusable because the muscle fibers shorten and fibrosis (scarring) occurs in connective tissue.
By age 10, braces may be required for walking, and by age 12, most patients are confined to a wheelchair. Bones develop abnormally, causing skeletal deformities of the spine and other areas.
Muscular weakness and skeletal deformities contribute to frequent breathing disorders. Cardiomyopathy occurs in almost all cases. Intellectual impairment may occur, but it is not inevitable and does not worsen as the disorder progresses.
Duchenne muscular dystrophy occurs in approximately 2 out of 10,000 people. Because this is an inherited disorder, risks include a family history of Duchenne muscular dystrophy. In contrast, Becker muscular dystrophy is a form that progresses (gets worse) much more slowly.
Symptoms
• Muscle weakness
o Rapidly progressive
o Frequent falls
o Difficulty with motor skills (running, hopping, jumping)
• Progressive difficulty walking
o Ability to walk may be lost by age 12
• Fatigue
• Intellectual retardation (possible)
• Skeletal deformities
o Chest and back (scoliosis)
• Muscle deformities
o Contractures of heels, legs
o Pseudohypertrophy of calf muscles
Exams and Tests
Muscle wasting (atrophy) begins in the legs and pelvis, then progresses to the muscles of the shoulders and neck, followed by loss of arm muscles and respiratory muscles. Calf muscle enlargement (pseudohypertrophy) is quite obvious.
Cardiomyopathy is commonly present, but signs of congestive heart failure or arrhythmias (irregular heartbeats) are rare. Respiratory disorders are common during the later stages, including pneumonia and aspiration of food or fluid into the lungs.
• A serum CPK is highly elevated.
• A neurological exam shows weakness and lack of coordination or balance.
• An EMG (electromyography) shows that weakness is caused by destruction of muscle tissue, rather than nerve damage.
• A muscle biopsy confirms the diagnosis.
Treatment
There is no known cure for Duchenne muscular dystrophy. Treatment is aimed at control of symptoms to maximize the quality of life. Gene therapy may become available in the future.
Activity is encouraged. Inactivity (such as bedrest) can worsen the muscle disease. Physical therapy may be helpful to maintain muscle strength and function. Orthopedic appliances (such as braces and wheelchairs) may improve mobility and the ability for self-care.
Support Groups
The stress of illness can often be helped by joining a support group where members share common experiences and problems. See muscular dystrophy - support group. The Muscular Dystrophy Association is an excellent source of information on this disease.
Outlook (Prognosis)
Duchenne muscular dystrophy results in rapidly progressive disability. Death usually occurs by age 25, typically from respiratory (lung) disorders.
Possible Complications
• Deformities
• Permanent, progressive disability
o Decreased mobility
o Decreased ability for self-care
• Mental impairment (varies, usually minimal)
• Pneumonia or other respiratory infections
• Respiratory failure
• Cardiomyopathy
• Congestive heart failure (rare)
• Heart arrhythmias (rare)
When to Contact a Medical Professional
Call your health care provider if your child has symptoms that indicate Duchenne muscular dystrophy.
Call your health care provider if symptoms worsen, or new symptoms develop, particularly fever with cough or breathing difficulties.
Prevention
Genetic counseling is advised if there is a family history of the disorder. Duchenne muscular dystrophy can be detected with about 95% accuracy by genetic studies performed during pregnancy.
Pseudohypertrophic muscular dystrophy; Muscular dystrophy - Duchenne type
Definition
Duchenne muscular dystrophy is an inherited disorder, characterized by rapidly-worsening muscle weakness that starts in the legs and pelvis, and later affects the whole body.
Causes
Duchenne muscular dystrophy is a rapidly-worsening form of muscular dystrophy. It is caused by a defective gene for dystrophin (a protein in the muscles). However, it often occurs in people without a known family history of the condition. This disorder is marked by worsening loss of muscle function, which begins in the lower limbs.
Duchenne muscular dystrophy is inherited in what is known as an X-linked recessive pattern. The defective gene is found on the X chromosome. Because women have two X chromosomes, if one contains a normal copy of the gene, that gene will make enough of the protein to prevent symptoms. But boys have an X chromosome from their mother and a Y from father, so if the X chromosome is defective, there is no second X to make up for it and they will develop the disease.
The sons of carrier females (women with one defective chromosome but no symptoms themselves) each have a 50% chance of having the disease, and the daughters each have a 50% chance of being carriers.
Symptoms usually appear before age 6 and may appear as early as infancy. There is progressive muscle weakness of the legs and pelvis, which is associated with a loss of muscle mass (wasting). Muscle weakness also occurs in the arms, neck, and other areas, but not as severely or as early as in the lower half of the body.
Calf muscles initially grow larger -- the enlarged muscle tissue is eventually replaced by fat and connective tissue (a condition called pseudohypertrophy). Muscle contractures occur in the legs. Thus, the muscles are unusable because the muscle fibers shorten and fibrosis (scarring) occurs in connective tissue.
By age 10, braces may be required for walking, and by age 12, most patients are confined to a wheelchair. Bones develop abnormally, causing skeletal deformities of the spine and other areas.
Muscular weakness and skeletal deformities contribute to frequent breathing disorders. Cardiomyopathy occurs in almost all cases. Intellectual impairment may occur, but it is not inevitable and does not worsen as the disorder progresses.
Duchenne muscular dystrophy occurs in approximately 2 out of 10,000 people. Because this is an inherited disorder, risks include a family history of Duchenne muscular dystrophy. In contrast, Becker muscular dystrophy is a form that progresses (gets worse) much more slowly.
Symptoms
• Muscle weakness
o Rapidly progressive
o Frequent falls
o Difficulty with motor skills (running, hopping, jumping)
• Progressive difficulty walking
o Ability to walk may be lost by age 12
• Fatigue
• Intellectual retardation (possible)
• Skeletal deformities
o Chest and back (scoliosis)
• Muscle deformities
o Contractures of heels, legs
o Pseudohypertrophy of calf muscles
Exams and Tests
Muscle wasting (atrophy) begins in the legs and pelvis, then progresses to the muscles of the shoulders and neck, followed by loss of arm muscles and respiratory muscles. Calf muscle enlargement (pseudohypertrophy) is quite obvious.
Cardiomyopathy is commonly present, but signs of congestive heart failure or arrhythmias (irregular heartbeats) are rare. Respiratory disorders are common during the later stages, including pneumonia and aspiration of food or fluid into the lungs.
• A serum CPK is highly elevated.
• A neurological exam shows weakness and lack of coordination or balance.
• An EMG (electromyography) shows that weakness is caused by destruction of muscle tissue, rather than nerve damage.
• A muscle biopsy confirms the diagnosis.
Treatment
There is no known cure for Duchenne muscular dystrophy. Treatment is aimed at control of symptoms to maximize the quality of life. Gene therapy may become available in the future.
Activity is encouraged. Inactivity (such as bedrest) can worsen the muscle disease. Physical therapy may be helpful to maintain muscle strength and function. Orthopedic appliances (such as braces and wheelchairs) may improve mobility and the ability for self-care.
Support Groups
The stress of illness can often be helped by joining a support group where members share common experiences and problems. See muscular dystrophy - support group. The Muscular Dystrophy Association is an excellent source of information on this disease.
Outlook (Prognosis)
Duchenne muscular dystrophy results in rapidly progressive disability. Death usually occurs by age 25, typically from respiratory (lung) disorders.
Possible Complications
• Deformities
• Permanent, progressive disability
o Decreased mobility
o Decreased ability for self-care
• Mental impairment (varies, usually minimal)
• Pneumonia or other respiratory infections
• Respiratory failure
• Cardiomyopathy
• Congestive heart failure (rare)
• Heart arrhythmias (rare)
When to Contact a Medical Professional
Call your health care provider if your child has symptoms that indicate Duchenne muscular dystrophy.
Call your health care provider if symptoms worsen, or new symptoms develop, particularly fever with cough or breathing difficulties.
Prevention
Genetic counseling is advised if there is a family history of the disorder. Duchenne muscular dystrophy can be detected with about 95% accuracy by genetic studies performed during pregnancy.
Saturday, April 5, 2008
103 - low molecular weight heparins
In medicine, low-molecular-weight heparin (LMWH) is a class of medication used as an anticoagulant in diseases that feature thrombosis, as well as for prophylaxis in situations that lead to a high risk of thrombosis.[1]
Heparin is a naturally-occurring polysaccharide that inhibits coagulation, the process whereby thrombosis occurs (see Heparin: Mechanisms of action). Natural heparin consists of molecular chains of varying lengths, or molecular weights. Chains of molecular weight from 5000 to over 40,000
Heparin derived from natural sources, mainly porcine intestine or bovine lung, can be administered therapeutically to prevent thrombosis (see anticoagulation). However, the effects of natural, or unfractionated heparin can be difficult to predict. After a standard dose of unfractionated heparin, coagulation parameters must be monitored very closely to prevent over- or under-anticoagulation.
Low-molecular-weight heparins (LMWHs), in contrast, consist of only short chains of polysaccharide. LMWHs are defined as heparin salts having an average molecular weight of less than 8000 Da and for which at least 60% of all chains have a molecular weight less than 8000 Da. These are obtained by various methods of fractionation or depolymerisation of polymeric heparin. They have a potency of greater than 70 units/mg of anti-factor Xa activity and a ratio of anti-factor Xa activity to anti-thrombin activity of >1.5.[3]
Low-molecular-weight heparin products
The anhydromannose in IdoA(2S)-anhydromannose can be reduced to an anhydromannitol
Various methods of heparin depolymerisation are used in the manufacture of low-molecular-weight heparin.[4] These are listed below:
- Oxidative depolymerisation with hydrogen peroxide. Used in the manufacture of ardeparin (Normiflo®)
- Deaminative cleavage with isoamyl nitrite. Used in the manufacture of certoparin (Sandoparin®)
- Alkaline beta-eliminative cleavage of the benzyl ester of heparin. Used in the manufacture of enoxaparin (Lovenox® and Clexane®)
- Oxidative depolymerisation with Cu2+ and hydrogen peroxide. Used in the manufacture of parnaparin (Fluxum®)
- Beta-eliminative cleavage by the heparinase enzyme. Used in the manufacture of tinzaparin (Innohep® and Logiparin®)
- Deaminative cleavage with nitrous acid. Used in the manufacture of dalteparin (Fragmin®), reviparin (Clivarin®) and nadroparin (Fraxiparin®)
Deaminative cleavage with nitrous acid results in the formation of an unnatural anhydromannose residue at the reducing terminal of the oligosaccharides produced. This can subsequently be converted to anhydromannitol using a suitable reducing agent as shown to the left.
UA(2S)-GlcNS(6S)
Likewise both chemical and enzymatic beta-elimination result in the formation of an unnatural unsaturated uronate residue(UA) at the non-reducing terminal, as shown to the left.
Differences between low molecular weight heparin products
Comparisons between LMWHs prepared by similar processes vary. For example, a comparison of Dalteparin and Nadroparin suggests they are more similar than products produced by different processes. However comparison of enoxaparin and tinzaparin shows they are very different from each other with respect to chemical, physical, and biological properties.
As might be expected, products prepared by distinctly-different processes are dissimilar in physical, chemical, and biological properties.
see references.[5][6][7][8][9][10].
Differences from unfractionated heparin
Its differences with unfractioned heparin include:
- Average molecular weight: heparin is about 20000 Da and LMWH is about 3000 Da
- Once-daily dosing, rather than a continuous infusion of unfractionated heparin
- No need for monitoring of the APTT coagulation parameter
- Possibly a smaller risk of bleeding
- Smaller risk of osteoporosis in long-term use
- Smaller risk of heparin-induced thrombocytopenia, a feared side-effect of heparin.
- The anticoagulant effects of heparin are typically reversible with protamine sulfate, while the effect on LMWH is limited
- Has less of an effect on thrombin compared to heparin, but maintains the same effect on Factor Xa.
Clinical uses
Because it can be given subcutaneously and does not require APTT monitoring, LMWH permits outpatient treatment of conditions such as deep vein thrombosis or pulmonary embolism that previously mandated inpatient hospitalization for unfractionated heparin administration
The use of LMWH needs to be monitored closely in patients at extremes of weight or in-patients with renal dysfunction. An anti-factor Xa activity may be useful for monitoring anticoagulation. Given its renal clearance, LMWH may not be feasible in patients that have end-stage renal disease.
Use in venothromboembolic disease associated with cancer
The CLOT study, published in 2003, showed that, in patients with malignancy and acute venous thromboembolism, dalteparin was more effective than coumarin in reducing the risk of recurrent embolic events.[11]
References
- ^ Weitz JI (1997). "Low-molecular-weight heparins". N Engl J Med 337 (10): 688-98. PMID 9278467.
- ^ Linhardt, R.J. Gunay, N. S. (1999). "Production and chemical processing of low molecular weight heparins". Sem. Thromb. Hem. 25 (3): 5-16.
- ^ European Pharmacopedia Commission (1991). "{{{title}}}". Pharmeuropa 3: 161-165.
- ^ Linhardt, R.J. Gunay, N. S. (1999). "Production and chemical processing of low molecular weight heparins". Sem. Thromb. Hem. 25 (3): 5-16.
- ^ Green, D. Hirsh, J. Heit, J. et al (1991). "Low molecular weight heparin: A critical analysis of clinical trials". Pharmacol. Rev. 2: 45-50.
- ^ Barrowcliffe, T. W. (1995). "Low molecular weight heparin(s)". Br. J. Haematol. 90: 1-7.
- ^ Donayre C. E. (1996). "Current use of low molecular weight heparins". Semin. Vascul. Surg. 9: 362-371.
- ^ Hunt, D. (1998). "Low molecular weight heparins in clinical practice". Southern Medical J. 91: 2-10.
- ^ Fareed, J. Jeske, W. Hoppensteadt, D. Clarizio, R. Walenga, J. M. (1998). "Low molecular weight heparins: Pharmacologic profile and product differentiation". Am. J. Cardiol. 82: 3L-10L.
- ^ Ramos-Sánchez MC, Barrio-Arredondo MT, De Andrés Santos AI, MartÃn-Gil J, MartÃn-Gil F.J. (1995). "Thermal analysis of aqueous solutions of heparins". Thermochim Acta 262: 109-115.
- ^ Lee AY, Levine MN, Baker RI, Bowden C, Kakkar AK, Prins M, Rickles FR, Julian JA, Haley S, Kovacs MJ, Gent M (2003). "Low-molecular-weight heparin versus a coumarin for the prevention of recurrent venous thromboembolism in patients with cancer". N Engl J Med 349 (2): 146-53. PMID 12853587.
102 - enoxaparin
How does it work?
Enoxaparin is a medicine known as a low molecular weight heparin. It is an anti-clotting or anticoagulant medicine, and works by interfering with the body's natural blood clotting mechanism.
What is it used for?
Angina not well controlled by medical treatment
Blood clot lodged in a vein of the leg
Heart attack
Prevention of blood clot formation in the veins after surgery
Prevention of blood clot formation in the veins in people bedridden due to illness
Prevention of blood clots during haemodialysis
Warning!
This medicine is not recommended for use in children as no dose has been established.
It is recommended that blood tests to monitor the levels of platelets in the blood are performed prior to and during treatment with this medicine.
Blood potassium levels should be measured before starting treatment and at regular intervals throughout, particularly if treatment lasts longer than 7 days.
Use with caution in
Decreased liver function
Diabetes affecting the eyes
History of reduced platelet count (thrombocytopenia) caused by heparin treatment
People who have previously had a peptic ulcer
People who have recently had a stroke
People who have recently had eye surgery
People who have recently had surgery of the brain or spinal cord (neurosurgery)
People with problems stopping bleeding
Severe uncontrolled high blood pressure
Severely decreased kidney function
Not to be used in
Active peptic ulcer
Bacterial infection of the heart valves and the lining surrounding the heart (bacterial endocarditis)
Major bleeding disorders such as haemophilia
People with an increased risk of bleeding (haemorrhage)
Reduced platelet count in the blood
Stroke associated with internal bleeding of the brain
This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.
Pregnancy and Breastfeeding
Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
This medicine is not recommended for use in pregnancy unless considered essential by your doctor. Seek medical advice from your doctor.
It is not known whether this medicine passes into breast milk. Mothers who need to take this medicine should not breastfeed. Seek medical advice from your doctor.
Side effects
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.
Allergy to active ingredients (hypersensitivity)
Alteration in results of liver function tests
Bleeding (haemorrhage)
High blood potassium level (hyperkalaemia)
Thinning of the bones (osteoporosis) with long term use
Decrease in the number of platelets in the blood (thrombocytopenia)
Presence of blood clots in the spinal cord (intra-spinal haematoma)
Blood clots which form a solid swelling at the injection site (haematoma)
Pain and irritation at the injection site
Death of skin cells (necrosis) at the site of injection
The side effects listed above may not include all of the side effects reported by the drug's manufacturer.
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