Peripheral neuropathy in allergic granulomatous angiitis.

A 61-year-old woman began to suffer bronchial asthma in 1985. She then developed low back pain and numbness along the lower extremities, eventually leading to bilateral drop foot in 1990. At that time, she was diagnosed as having lumbar disc hernia, and extirpation of the discs at the L3-4 and L4-5 was performed. However, her clinical condition showed little improvement. Six months later, she was emaciated and bedridden with distal dominant muscular atrophy in all four limbs, purpura in the left leg and hypereosinophils. Motor conduction velocity (MCV) was not detected in the peroneal nerves. The toes gradually became cyanotic, and a skin biopsy from the cyanotic region revealed necrosis in the vessels surrounded by infiltration of a large number of neutrocytes and lymphocytes. She was diagnosed as having mononeuritis multiplex due to allergic granulomatous angiitis (AGA), which is characterized by bronchial asthma, hypereosinophilia and necrotizing vasculitis. Thirty mg/day prednisolone was then administered. However, the toes and calcaneal areas gradually became necrosed. Finally, amputation of both feet was necessary. We concluded that an early diagnosis of this syndrome is most important, and corticosteroids should be administered early.