2 OUTBREAKS OF ARSENIC REACTIVE ENCEPHALO PATHY AMONG PATIENTS TREATED FOR AFRICAN TRYPANOSOMIASIS, UGANDA, 1992-1993

Since 1988, the french non-governmental organisation Medecins Sans Fro ntieres is running a control program of human african trypanosomiasis in the district of Moyo, North-Uganda. Between 1988 and 1993, more tha n 7,000 patients were diagnosed and treated. Since 1988, it has been n oted that incidence of melarsoprol reaction had increased systematical ly between June and October of each year, indicating strong seasonal v ariation. In 1992 and 1993, two outbreaks of arsenical reactive enceph alopathy (ARE) occurred in the sleeping sickness center of Adjumani. T he incidence of ARE suddenly exceeded 10% of the patients treated by m elarsoprol during August 1992 and September 1993. The onset of 80% of those ''epidemic'' cases, occurred between the 5th and the 11th day of treatment. Two retrospective studies were conducted in 1992 (75 cases ) and in 1993 (51 cases). Among the risk factors studied, two appear t o increase the risk of ARE: the prescription of thiabendazole to treat strongyloidiasis during the melarsoprol cure and the bad general clin ical conditions of patients. These observations suggest that exogenous co-factors could be involved in the occurrence of ARE. Recommandation s were to. avoid administration of diffusible anti-helminthic treatmen t during the cure, and to improve the general conditions of patients b efore the cure of melarsoprol.