De novo multiple endocrine neoplasia type 2B with noncardiogenic pulmonary edema as the presenting symptom.

Multiple endocrine neoplasia (MEN) type 2B is a rare hereditary disorder characterized by medullary thyroid carcinoma, pheochromocytoma, and neuroma. Early signs of MEN 2B are usually neuroma, gastrointestinal problems, and medullary thyroid carcinoma. Noncardiogenic pulmonary edema is rare as a presenting symptom. We report a 31-year-old male who was admitted to our hospital because of noncardiogenic pulmonary edema. He was 168 cm in height, weighed 55 kg, and had an arm span of 166 cm. No marfanoid habitus was evident, but thickened lips and tongue neuroma were present. Chronic constipation had been present since childhood, and the patient had a two-year history of untreated hypertension. Noncardiogenic pulmonary edema and toxic megacolon were noted, and abdominal computed tomography revealed bilateral adrenal tumors. Ultrasonography of the thyroid showed two mass lesions. Intubation and mechanical ventilation were performed because of severe hypoxemia. Endocrinological examinations showed high levels of serum and urinary fractionated catecholamines, serum calcitonin, serum carcinoembryonic antigen, and serum intact parathyroid hormone. It was suggested that the high level of catecholamine from pheochromocytoma had caused the pulmonary edema. RET gene analysis showed a codon 918 mutation in exon 16 resulting in an ATG (methionine) to ACG (threonine) substitution, but analysis of the patient's parents showed the wild type. Therefore, the patient was diagnosed as having de novo MEN 2B. He underwent laparoscopic bilateral adrenectomy and total thyroidectomy. However, the values of serum calcitonin and CEA did not decrease to the normal ranges. Patients with early-stage MEN 2B have distinct characteristics that can aid early detection of the disease, thus possibly allowing them to be saved.