[Anti-Toxoplasma gondii IgG antibodies in HIV-infected patients]

Toxoplasma gondii infection is mostly asymptomatic, since multiplication of the parasites is limited by immunological mechanisms. Immunocompromised patients are an exception. Immunity decrease in HIV-infected persons results in opportunistic infections, including toxoplasmosis reactivation. The basis of the diagnosis are serological investigations, revealing IgM, IgA and IgG antibodies in serum. In HIV-infected patients their titres are often low, what makes disease phase definition and therapeutic decisions difficult. Another marker of toxoplasmosis activity is the determination of IgG antibodies avidity. The aim of the study was determination of anti-T. gondii IgG antibodies presence and their avidity in HIV-infected patients with respect to CD4 lymphocyte count. The results suggest no effect of IgG antibodies presence on CD4 lymphocyte count. Low titres of IgG antibodies were noted in the patients but the high avidity index of the determined antibodies indicated chronic T. gondii infection.