An observational study to detect leptospirosis in Mumbai, India, 2000.

BACKGROUND Leptospirosis is relatively uncommon in children. Following torrential rains and flooding an outbreak of leptospirosis was suspected in Mumbai. AIMS To investigate the possibility of an outbreak of leptospirosis and describe the clinical illness. METHODS From 24 July to 14 September 2000, children with a history of abrupt onset of high fever (>39 degrees C), who presented to our hospital, were admitted and tested serologically for anti-Leptospira antibodies by a quantitative enzyme linked immunosorbent assay (ELISA) test. An IgM titre of more than 20U/ml confirmed the diagnosis of leptospirosis. Clinical features in the confirmed leptospirosis and leptospirosis negative groups were analysed. RESULTS Of 53 children screened, 18 (34%) had leptospirosis. In all 18, the disease was anicteric and responded well to intravenous penicillin. Four clinical features present at the time of admission were significantly associated with leptospirosis: a history of contact with flood water (18/18 v 16/35), conjunctival suffusion (5/18 v 1/35), abdominal pain (9/18 v 5/35), and skin rash (5/18 v 1/35). As the number of these four features concomitantly present increased, the chances of the child having leptospirosis also increased significantly. A history of contact with flood water had a sensitivity of 100%, and the presence of conjunctival suffusion, abdominal pain, and skin rash had a specificity of 97%, 86%, and 97%, respectively, for identifying children with leptospirosis. CONCLUSION Leptospirosis should be suspected in febrile children with contact with flood water.