Neurofibromatosis and leprosy'

SUMMARY Two patients with neurofibromatosis and leprosy are reported. Both had active lepro-matous leprosy and generalized neurofibromata. The bacilli appear in huge numbers within the cytoplasm of the cells making up the neurofibromata, which become distended and resemble lepra cells. Since these cells are believed to derive from Schwann cells, the findings in these patients sup-port the idea that leprosy affects nerves initially by proliferating in Schwann cells and producing changes within them. The coexistence of leprosy and neurofibromatosis in the same patient is interesting in that both appear to be disorders of the Schwann cell. Recent electron microscopic studies (Chino and Tsuruhara, 1968; Fisher and Vuzevski, 1968) have demonstrated that most cells in neurofibromata and acoustic tumours derive from Schwann cells. The evidence relates to the presence of a basement membrane 500A thick, unmyelinated axons invaginated into the cells, and a tendency for these cells to wrap themselves up in their own processes. In leprosy the traditional view, held by Dehio (1897) and elaborated by Khanolka