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What is Hirschsprung disease has association with which of the following conditions? and explain in detail?
Small number of patients with MEN 2A have associated Hirschsprung disease. In MEN2A/Hirschsprung disease variant aganglioneuromatosis may be found throughout the colon or in smaller segments. Characteristic features of MEN 2A are medullary carcinoma of thyroid, pheochromocytoma and parathyroid adenoma. Ref: Harrisons Internal Medicine, 16th Edition, Chapter 295, Pages 2231-34.