Axonal neuropathy, long limbs and bumpy tongue: think of MEN2B.

INTRODUCTION: Multiple endocrine neoplasia type 2 (MEN 2) is an uncommon autosomal dominant cancer syndrome which can be associated with nerve conduction abnormalities. METHODS: A 14-year-old boy with a family history of consanguinity developed progressive gait clumsiness, pes cavus, hypotonia, and mucosal tumors of the lips and tongue since the age of 3 years. At age 11 years, he was diagnosed with an hereditary motor neuropathy (Charcot-Marie-Tooth syndrome). RESULTS: Physical examination revealed a Marfanoid habitus, mucocutaneous verrucous tumors, thyroid nodules, and cervical adenopathy. Genetic testing demonstrated the p.M918T mutation in the RET gene, and blood tests showed elevated levels of calcitonin. CONCLUSIONS: Clinical suspicion in MEN2 is crucial for early diagnosis and subsequent therapy. Mucosal neuroma and a Marfanoid habitus are especially useful. Other neurologic manifestations should not disguise the endocrine disorder, because early diagnosis and treatment of medullary thyroid carcinoma determines the prognosis.