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 (> 39degreesC), 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.