Neurofibromatosis Type I, Pheochromocytoma, Fibrous Osseous Dysplasia, and Osteoporosis A Rare and Unusual Combination

摘要

Neurofibromatosis (NF) is a rare autosomal dominant inherited disease. It affects the central and peripheral neural system, skin, bones, and the vascular system. There are two distinct forms, type I, or von Reckling-hausen's disease (NF1) and type II (NF2). The most common form (1:3000-4000), occurring in 85% to 90% of all cases, is type I (NF1). The NF1 gene, a tumor suppressor gene, produces neurofibromin, which downregulates ras protein. Fibrous osseous dysplasia (FOD) is characterized by fibroblast-like spindle cells and osseous tissue. It occurs in the tibia or fibula during childhood.NF1 sometimes coexists with benign or malignant, unilateral or bilateral pheochromocytomas. Decreased bone mineral density has also been reported in NF1 patients with kyphoscoliosis.We present a 48-year-old man with neurofibromatosis type I, pheochromocytoma, FOD, and osteoporosis. To our knowledge, there is no other reported case of the combination of NF1, FOD, pheochromocytoma, and osteoporosis. A brief review of the relevant published data is presented.