Toxoplasma gondii seroprevalence in people newly diagnosed with HIV in Poland: implications for neurotoxoplasmosis risk assessment

INTRODUCTION: Toxoplasma gondii (T. gondii) remains the primary pathogen causing focal cerebral lesions in human immunodeficiency virus (HIV)-positive persons, despite the general reduction of the incidence of opportunistic infections with the wide rollout of antiretroviral therapy. Therefore, serology testing at baseline remains a standard of HIV care. The aim of our study was to investigate the prevalence of T. gondii immunoglobulin G (IgG) and IgM antibodies among people who have been newly diagnosed with HIV. MATERIAL AND METHODS: A retrospective analysis of medical records of individuals newly registered in Warsaw's HIV Outpatient Clinic from January 1, 2021, to April 4, 2023, was performed. Demographics, transmission mode, and HIV status data were analyzed. Toxoplasma IgM and IgG antibodies were assessed using VIDAS® (bioMérieux, Lyon, France). Stratification was based on IgG antibody presence and chi-square test used for group comparison using Quick Statistics Calculators (https://www.socscistatistics. com/, accessed on November 10, 2023). RESULTS: Among 464 healthcare clients, 92.0% were male, with men who have sex with men (MSM) as the main HIV transmission mode (76.1%). Toxoplasma IgM antibodies were present in one (0.2%) and IgG antibodies were present in 142 (30.6%) persons. The median age was 32 years [interquartile range (IQR): 26.25-40.0], median CD4+ count was 365.5 cells/μL (IQR: 263-506), and median HIV viral load 46,576 copies/mL (IQR: 8,762.25-187,585.25). Persons with Toxoplasma IgG present were more likely to be female (13.4% vs. 5.6%, p = 0.0043), ≥ 30 years old (69.0% vs. 56.5%, p = 0.0112), acquiring HIV through heterosexual contacts (23.9% vs. 11.8%, p = 0.0013), and through intravenous drug injections (2.8% vs. 0.0%, p = 0.0085). No significant differences in T. gondii IgG prevalence were observed in persons regarding CD4 count and HIV viral load. CONCLUSIONS: Positive T. gondii IgG antibodies were present in 30.6% of newly registered healthcare clients and IgM in one person. This reflects trends in the general population. Factors correlated with positive T. gondii IgG antibodies were female sex, older age, heterosexual contacts, and intravenous drug injection modes of HIV acquisition.