ELISA for the detection of specific IgM and IgG in human leptospirosis

Abstract

ELISA was used to detect specific IgM and IgG in sera from humans with current or past leptospirosis. A serological pattern of a high IgM titre (≥1280), or moderately increased IgM (160-640) in conjunction with a low IgG titre (≤20), with serovar copenhageni antigen was characteristic for approximately two-thirds of the sera from serovar icterohaemorrhagiae patients obtained in the first two months of the disease. The antigen was the supernatant of a heated and centrifuged culture of leptospires. Antigens were prepared from serovars copenhageni, grippotyphosa, hardjo and patoc. Sera from patients with icterohaemorrhagiae, grippotyphosa and hardjo infections showed cross-reactivity when different antigens were used. In past infections the IgG titres were clearly higher with the homologous antigen. ELISA for IgM and IgG allows the rapid diagnosis of acute leptospirosis.