[A case of leptospirosis diagnosed early by flaB-PCR].

We report a case of leptospirosis that was diagnosed in the early stage of infection by using flaB-PCR. The flaB gene of Leptospira was amplified from the DNA extract of the patient's blood at hospital day 1, while leptospiral antibody was negative by the method of microscopic agglutination test and micocapsule agglutination test at that time. Seroconversion occurred at hospital day 6 and Leptospira was isolated from the patient's blood at hospital day 16, demonstrating that flaB-PCR method was very useful in early diagnosis of leptospirosis.