[The diagnosis of leptospirosis in the hospital microbiology laboratory].

Confirmatory diagnosis of clinical leptospirosis may be achieved by each hospital laboratory performing all-purpose bacteriological methods. Direct microscopic examination of blood may frequently demonstrate circulating leptospiras in the first few days of pyrexia. Leptospiras may be tentatively cultured from blood in the same initial period of illness, in fluid semisynthetic commercial media according to the original Ellinghausen medium. Sero-conversion for leptospira antibodies is constantly observed on two serum samples taken in the first few days of illness and ten days thereafter respectively, in each case of current leptospirosis.