Difference in Toxoplasma gondii Seroprevalence Rates Due to Low and High CD4 Counts in Patients with HIV/AIDS

Since symptomatic toxoplasmosis in in human immunodeficiency virus (HIV)/Acquired immunodeficiency syndrome (AIDS) almost always occurs as a result of reactivation of chronic infection, screening Toxoplasma serology has an important role in the follow up of the main disease in these populations. In this meta-analysis, we aimed to reveal the difference in the seroprevalence rates of Toxoplasma gondii infection between groups in relation to CD4 counts (CD4-counts ≥200 and <200 cells/mm³) HIV-infected population.

The meta-analysis was performed by searching for the studies in English that were published in the last 20-year period in databases including PubMed, Google Scholar, Embase, Science Direct and Web of Science. The process of searching was carried out using the keywords: “Acquired immunodeficiency syndrome”, “AIDS”, “Human immunodeficiency virus”, “HIV”, “Toxoplasma”, “Toxoplasmosis”, “Toxoplasma gondii”, “seroprevalence”, “prevalence” and “immunoglobulin G”.

A total of 16 studies including 3982 seropositive samples of T. gondii, 2792 of which were in first group (HIV positive patients with CD4-counts ≥200 cells/mm³) and 1190 were in second group (HIV positive patients with CD4-counts <200 cells/mm³), were included in the meta-analysis. The seroprevalence of T. gondii was 40.03% in HIV-positive patients with CD4 counts ≥200 cells/mm³, and 43.5% in the group with CD4 counts <200 cells/mm³. Seroprevalence rates in the studies included in the meta-analysis showed variability (heterogeneity) in both groups and heterogeneity between studies was higher in group 1 [Group 1; Cochran Q=994.16, DF=15, I²=98.49%, p<0.0001 and group 2; Cochran Q=368.50, DF=15, I²=95.93%, p<0.0001].

We concluded that HIV/AIDS patients with low CD4 counts have higher epidemiological risk as well as immunological risk of toxoplasmosis. To the best of our knowledge, this is the first meta-analysis evaluating the seroprevalence of T. gondii in AIDS/HIV population by comparing the seroprevalance of T. gondii in subgroups formed according to CD4 counts.