Prozone effects in microscopic agglutination tests for leptospirosis in the sera of mice infected with the pathogenic Leptospira interrogans serovar Canicola

• Published in: Memórias do Instituto Oswaldo Cruz Vol. 108; no. 5; pp. 668 - 670
• Main Authors: Shimabukuro, Fabio Hiroto, Costa, Veruska Maia da, Silva, Rodrigo Costa da, Langoni, Hélio, da Silva, Aristeu Vieira, de Carvalho, Lídia Raquel, Domingues, Paulo Francisco
• Format: Journal Article
• Language: English; Portuguese
• Published: Brazil Instituto Oswaldo Cruz, Ministério da Saúde 01.08.2013; Fundação Oswaldo Cruz (FIOCRUZ)
• Subjects: Agglutination Tests; Animals; Antibodies, Bacterial - blood; Antibodies, Bacterial - immunology; Enzyme-Linked Immunosorbent Assay; Female; Humans; Leptospira interrogans; Leptospira interrogans serovar canicola - immunology; leptospirosis; Leptospirosis - diagnosis; Leptospirosis - microbiology; Mice; microscopic agglutination test; PARASITOLOGY; prozone effect; Technical Notes; Treponema pallidum; TROPICAL MEDICINE; prozone effect; leptospirosis; microscopic agglutination test
• ISSN: 0074-0276; 1678-8060; 1678-8060; 0074-0276
• DOI: 10.1590/0074-0276108052013022

Mice experimentally infected with a pathogenic strain of Leptospira interrogans serovar Canicola produced false negative results (prozone effect) in a microscopic agglutination test (MAT). This prozone effect occurred in several serum samples collected at different post-infection times, but it was more prominent in samples collected from seven-42 days post-infection and for 1:50 and 1:100 sample dilutions. This phenomenon was correlated with increased antibody titres in the early post-infection phase. While prozone effects are often observed in serological agglutination assays for the diagnosis of animal brucellosis and human syphilis, they are not widely reported in leptospirosis MATs.