Sero-prevalence of cryptococcal antigen and its immune-virological correlates in HIV-1 positive individuals: a prospective cross-sectional study

Abstract

Background: Cryptococcal infection remains a leading cause of mortality among HIV-1-positive individuals, particularly in regions with limited access to antiretroviral therapy and diagnostics. This study aimed to assess Cryptococcal Antigen (CrAg) seroprevalence and its immune-virological correlates among ART-naïve and ART-experienced HIV-1 positive individuals.

Methods: This prospective cross-sectional study was conducted from May 2023 to August 2024 at Edo State University Teaching Hospital, Nigeria. Blood samples were analyzed for CD4 + T-cell counts using a Partec™ CyFlow analyzer, HIV-1 viral load using the COBAS^® AmpliPrep/COBAS^® TaqMan^® Test, and CrAg detection with the Immy Latex-Crypto Antigen Lateral Flow Assay.

Results: Among 229 HIV-1 positive individuals, 72.5% were aged 15-20 years, and 69% were female. Most (68.6%) were ART-experienced, while 31.4% were ART-naïve. Severe immunosuppression (CD4 + < 200 cells/mm³) was present in 64.6%, and 71.2% had viral loads > 1,000 copies/mL. Cryptococcal infection (CI) prevalence was 10.04%. No significant link was found between CI and age or gender, but ART-naïve status, low CD4 + counts, and high viral loads were significantly associated with CI. ART-naïve individuals had higher viral loads (median 4.95 vs. 4.19 log10 copies/mL, p = 0.00). A stronger inverse correlation between CD4 + counts and viral load was observed in ART-experienced patients (r = -0.535).

Conclusions: These findings emphasize the necessity for routine Cryptococcal screening, particularly in ART-naïve and severely immunocompromised individuals, to facilitate timely interventions and improve clinical outcomes.

Keywords: ART; CD4 + T-cell counts; Cryptococcal antigen; HIV-1; Immune-Virological correlates; Sero-Prevalence; Viral load.

Fig. 1

Comparison of CD4 T-cell count and HIV-1 Viral Load among Cryptococcal positive individuals. Dots represent each participant along the predefine levels of CD4 T-cell counts and HIV-1 viral Load. A represent CD4 T-cell counts levels. B represents HIV-1 Viral Load; Mann-whitney test (P ≤ 0.05)

Fig. 2

Correlation analysis between CD4 T-cell counts-HIV-1 viral load of ART Naïve and CD4 T-cell counts- HIV-1 viral load of ART Experienced individual positive with CrAg. A represents the CD4 T-cell counts-HIV-1 viral load of ART Naïve and B represents the CD4 T-cell counts-HIV-1 viral load of ART Experienced individual positive with crAg. (P ≤ 0.05)