Objective: Toxoplasmosis is an infection caused by Toxoplasma gondii which is an obligate intracellular parasite. It generally courses as an asymptomatic infection, but it can lead to life threatening infections in pregnant women and immunocompromised patients.

In this study, we investigated retrospectively the distribution of anti-T. gondii IgG, IgM and IgG avidity test results in blood samples of suspect toxoplasmosis patients sent to the laboratory of the Department of Medical Microbiology.

Method and Method: In this study, blood samples sent to the Medical Microbiology Laboratory with suspected toxoplasmosis between October 2014 and October 2015 were analyzed with anti-T. gondii IgG, IgM and IgG avidity tests using Enyzme Linked Fluorescein Assay (ELFA).

Results: Anti-T. gondii IgG and IgM antibodies were found to be positive in 39.3% (247/628) and 6% (64/1050) of the patients tested, respectively. Anti T. gondii avidity was tested in 159 patients and it is evaluated as high avidity in 133 (83.6%), low avidity in 15 (9.4%) and borderline avidity indices in 11 (6.9%) of these patients.

Conclusion: Although the reliability of antibody tests is variable in immunocompromised patients, IgG avidity test is considered to be useful in diagnosis.