Dapsone-induced peripheal neuropathy following chronic intake of therapeutic doses of dapsone'*"-8~'0~1z has been reported. In the Philippines, dapsone is readily available and dispensed in large quantities because of the high incidence of leprosy. We report about a case of peripheral neuropathy developing acutely after a suicidal ingestion of 6 g dapsone.A 17-year-old female, Filipina, was admitted because of cyanosis. A day earlier she had ingested 60 tablets of the 100 mg preparation of dapsone (Avlo-sulfon@). Hours later she developed dizziness and headaches. Later she suddenly experienced severe abdominal pain, vomiting, and cyanosis of the lips and nailbeds arid was admitted. Dapsone tablets were readily available in the house because an aunt who lives with the family had leprosy arid was undergoing treatment.On admission she was awake but restless, moving all her extremities equally. Deep tendon reflexes were normoactive, and no pathologic reflexes were elicited. On the fifth day, a steppage gait was noted. Neurologic evaluation revealed that she had mild weakness of the distal muscles of the lower extremities and had bilateral footdrop. Ankle jerks were absent, whereas the other reflexes were normoactive. There was equivocal impaired pinprick and light touch sensations up to the ankle level. Vibration and position senses were intact. There were no sensory or motor deficits in both upper extremities. On the 30th day, nerve stimulation studies revealed absent evoked motor responses in peroneal nerves, whereas the motor latencies, amplitudes, arid conduction velocities of the median and tibia1 nerves were normal. The left surd nerve conduction velocity was 42 misec (normal >40 misec) and had a reduced amplitude (8 pV; normal >10 JLV).Few fibrillations and positive waves were noted on both tibialis anterior muscles. A left sural nerve biopsy was performed at the ankle level on the same day. As we described b e f~r e ,~ after the nerve was fixed in glutaraldehyde and osmicated, we prepared single teased fiber preparations, semithin sections for histogram, and ultrathin sections for electronmicroscopy. From 100 sin-gle teased fiber nerve preparations, 24% showed linear rows of myelin ovoids coresponding to condition E of Dyck's classification* (Fig. 1 A ) . Semithin transverse sections disclosed similar findings consisting of a mild subperineurial edema and scattered myelin ovoicls or balls (Fig. 1B). No evident clustering of small inyelinated fibers was noted. The myelinated fiber histogram showed a preserved bimodal distribution and the densities of total, large, and small fibers (Fig. 1C). Ultrathin sections revealed varying degrccs of disintegration of the axixi with or without myelin breakdown. Other than thc occasional myelin debris noted in cytoplasm, the Schwann cells did not show reniarkable changes.Existence of' peripheral neuropathy is proven here clinically, electrophysiologically, and pathologically. As in most other previous cases, this present case also had predorriinantly motor syniptoniatology....
