125 - diagnose this case 2

2^nd case: a 25 year old young woman has recurrent episodes of headache and sweating. Her mother had renal calculi and died after having a neck mass. The physical examination reveals a thyroid nodule but no clinical sign of thyrotoxicosis. Before performing thyroid surgery , the surgeon should order ?

1. measurement of thyroid hormones
2. serial determinations of serum calcium, phosphorous protein and alkaline phosphatase
3. 24 hours urine test for 5 HIAA excretion
4. Serial 24 hours test for catecholamines,metanephrines and vanillylmandelic acid excretion

Answer : d . pheochromocytoma must be excluded by measurement of urinary catecholamines levels in all cases before embarking upon thyroid surgery to avoid the potential hazards of this condition .

Assays employed for diagnosis of pheochromocytoma include those for :

1. vanillyl mandelic acid
2. metanephrines
3. free catecholamines

- the patient in question is a case of inherited MEN 2a syndromes . the presence of headache and sweating in a patient with thyroid nodule warrants prompt investigation for a possible pheochromocytoma as part of MEN 2 syndrome , more so in a patient with a positive familiy history ( as suggested by presence of renal calculi and thyroid nodule in mother )

- pheochromocytoma secrete large amounts of catecholamines , the secretion of which is further increased during surgery . this may result in large swings in blood pressure and arrythmias, and increases the risk of surgical mortality. Stable alpha adrenergic blockage is essential before embarking on thyroid surgery .

--- the option c is concerned with the diagnosis of carcinoid syndrome .

--- serum calcium and phosphorous alkaline phosphatase may aid in the diagnosis of hyperparathyroidism a part of MEN 2a but again offer no specific advantage to surgeons prior to surgery of thyroid .

124 - diagnose this case 1

1^st case : a 20 year old male presented with chronic constipation, headache and palpitations . on examination he had marfanoid habitus, neuromas of tongue , medullated corneal nerve fibres and nodule of 2 x 2 cms size in the left lobe of thyroid gland . the patient is a case of ?

1. sporadic medullary carcinoma of thyroid
2. familial medullary carcinoma of thyroid ( FMCT )
3. MEN 2a
4. MEN 2b

Answer : d. MEN 2b.

Explanation : the association of medullary carcinoma of thyroid and pheochromocytoma, with mucosal neuromas and marfanoid habitus is designated MEN 2b .

Mucosal neuromas and marfanoid habitus are the most distinctive features of MEN 2b and are recognized in childhood.

True neuromas are present on the tip of the tongue, under the eyelids and throughout the gastrointestinal tract and are tree neuromas distinct from neurofibromas .

1.the features of WERNER syndrome or MEN 1 are :

- parathyroid hyperplasia or adenoma

- pituitary hyperplasia or adenoma

- pancreatic islet cell hyperplasia or adenoma or carcinoma

other less common features of MEN 1 are :

- foregut carcinoid

- pheochromocytoma

- subcutaneous or visceral lipomas

- dermal angiofibromas and

- collagenomas

2. the features of MEN 2a are :

- pheochromocytoma

- medullary carcinoma of thyroid

- parathyroid hyperplasia or adeonoma

other less common features of MEN 2a are : ( chf )

- cutaneous lichen amyloidosis

- hirschsprung disease

- familial medullary thyroid cancer ( FMTC )

3. the features of MEN 2b are :

- medullary thyroid cancer

- pheochromocytoma

- mucosal and gastrointestinal neuromas

less common features of MEN 2b are :

- marfanoid habitus .

--- remember MEN 1 is otherwise called WERNER syndrome and MEN 2 is called SIPPLE syndrome .