Obtain full history of
gastrointestinal symptoms, failure to thrive, and associated endocrine or
neurologic diseases. Evaluate patient's intravascular volume status:
clinically, plasma electrolytes, coagulation profile, and hemoglobin level. If on total parenteral
nutrition, obtain albumin, glucose, phosphate, calcium, and magnesium
levels, liver function tests. In rare cases of associated MEN IIA (medullary thyroid
carcinoma, parathyroid adenoma, pheochromocytoma) or MEN IIB (medullary thyroid
carcinoma, mucosal neuromas [tongue, buccal mucosa, lips, conjunctivae,
pheochromocytoma]): request endocrine consultation.