Seroprevalence of Toxoplasma gondii infection among HIV-positive patients in Southwest Iran and associated risk factors: a case-control study

Abstract

Background: The current study aimed to determine the seroprevalence of Toxoplasma gondii infection among HIV-positive patients and healthy subjects.

Methods: This study was carried out on HIV-positive patients and healthy individuals in Southwest Iran. Five millilitres of venous blood samples were collected aseptically from each individual. Sera and buffy coats were isolated from each sample and evaluated for anti-Toxoplasma antibodies and T. gondii DNA using ELISA kit and real-time PCR, respectively. Statistical analysis was performed using SPSS 18 software.

Results: Of 64 AIDS/HIV-positive patients, six (9.3%, 95% CI 7.2 to 11.3%) were seropositive for only IgG and five (7.8%, 95% CI 6.0 to 9.5%) were seropositive for both IgG and IgM. Moreover, among 64 healthy controls, 10 (15.6%, 95% CI 12.1 to 19.0%) were seropositive for only IgG and 2 (3.1%, 95% CI 2.4 to 3.7%) were seropositive for both IgG and IgM. Toxoplasma gondii DNA was detected in six samples (9.3%, 95% CI 7.2 to 11.3%) in the AIDS/HIV-positive patients group and eight samples (5.95%, 95% CI 4.6 to 7.2%) in the control group using real-time PCR. Consumption of undercooked meat was documented as an associated risk factor for T. gondii seropositivity in AIDS patients (OR 4.06, 95% CI 0.966 to 17.09; p=0.045).

Conclusions: Our findings showed a lower prevalence of Toxoplasma infection in AIDS/HIV-positive patients vs healthy controls; however, a considerable number of AIDS/HIV-positive patients were also seen to be at risk of toxoplasmosis. Based on the findings, screening and prophylaxis for toxoplasmosis should be implemented for all AIDS/HIV-positive patients in Southwest Iran.

Keywords: Toxoplasma gondi; AIDS/HIV-positive patients; ELISA; case-control; real-time PCR.