Recurrent annual outbreaks of a hepato-myo-encephalopathy syndrome in children in western Uttar Pradesh, India

Abstract

Background & objectives: Outbreaks of an acute encephalopathy syndrome affecting children, with high case-fatality, have been reported in western Uttar Pradesh, India for the last many years.We investigated these cases in Bijnor district and present our findings. Methods: Fifty five children aged 2-10 yr hospitalized from 2003 to 2005 in Bijnor, Uttar Pradesh, with features of acute encephalopathy were selected by defined clinical criteria. Various laboratory investigations were performed. Results: The disease had peak incidence in early winter months. Previously healthy, 2-4 yr old rural children (mean age-3.78 yr) of very low socio-economic background were most vulnerable. Almost all had vomiting preceding unconsciousness and a majority had mild fever and abnormal behaviour/agitation. Abnormal posture of trunk and limbs were distinctive features. Fluctuation of blood pressure was seen in three-quarter cases. Serum aminotransferases, creatine phosphokinase and lactic dehydrogenase levels were found markedly raised virtually in all cases in whom the tests were performed. Serum glucose was found low (<50 mg/dl) in 47.3 per cent cases at presentation. Cerebrospinal fluid (CSF) was under normal or low pressure and without pleocytosis in all cases. No microorganism could be isolated from serum, CSF, urine and visceral specimens. Neuroimaging performed in two cases was also normal. Liver biopsy performed in 21 cases showed acute hepatotoxic injury in all with marked hydropic change and perivenular necrosis. Tibial muscle biopsy done in 8 cases showed focal necrosis while brain biopsy taken in 2 cases had mild spongiosis with focal gliosis. Forty two children succumbed to their illness (case fatality 76.4%), most within 72 h of presentation. Survivors did not show any neurological deficit. Interpretation & conclusion: Our findings showed that the outbreaks were due to a multi-system disease with toxic injury to liver, muscles and brain (hepato-myo-encephalopathy) and not due to viral encephalitis as believed so far. The cause remains unknown but several features suggest the possibility of phytotoxin-induced pathology.