Isolation of leptospires and demonstration of antibodies in human leptospirosis in Madras, India.

Among 25 clinically suspected cases of leptospirosis, organisms could be isolated from blood and urine of only 10 cases but demonstrated in 15 cases. Antibody titres at a low level were observed to one or more leptospiral antigens in all 25 cases. Nine of the repeated samples from 12 cases showed a four-fold rise in titre. The highest antibody titres were seen against autumnalis. The predominant clinical picture was of fever, myalgia, conjunctival suffusion and jaundice with renal involvement.