Neurological manifestations of snake bite in Sri Lanka.

BACKGROUND AND AIMS Snake bite is an important cause of mortality and morbidity in certain parts of Sri Lanka. This study was designed to determine the offending snakes, neurological manifestations, disease course, and outcome in neurotoxic envenomation. METHODS AND MATERIAL Fifty six consecutive patients admitted with neurological manifestations following snake bite were studied prospectively. Data were obtained regarding the offending snakes, neurological symptoms, time taken for onset of symptoms, neurological signs, and time taken for recovery. RESULTS The offending snake was Russell's viper in 27(48.2%), common and Sri Lankan krait in 19(33.9%), cobra in 3(5.4%), and unidentified in 7(12.5%). Ptosis was the commonest neurological manifestation seen in 48(85.7%) followed by ophthalmoplegia (75%), limb weakness (26.8%), respiratory failure (17.9%), palatal weakness (10.7%), neck muscle weakness (7.1%), and delayed sensory neuropathy (1.8%). Neurological symptoms were experienced usually within 6 hours after the bite. Following administration of antivenom, the signs of recovery became evident within a few hours to several days. The duration for complete recovery ranged from four hours to two weeks. CONCLUSIONS Complete recovery of neuromuscular weakness was observed in all patients except for one who died with intracerebral haemorrhage shortly after admission.