Gut Microbiome and Its Physiological Interaction with Immune Function in HIV-Positive Children in Abuja: A Preliminary Analysis

The gut microbiome plays a critical role in immune homeostasis, and its disruption in paediatric HIV infection may exacerbate immune dysfunction beyond the direct effects of the virus. This study conducted a preliminary analysis of gut microbiome composition and its relationship with immune function parameters in HIV-positive children receiving antiretroviral therapy in Abuja, North Central Nigeria. A cross-sectional design enrolled 40 HIV-positive children aged 5 to 12 years on stable antiretroviral therapy and 20 age-matched HIV-negative controls. Stool samples were analysed using 16S rRNA gene sequencing to characterise microbial diversity. CD4 count, viral load, and serum immunoglobulin G were measured from blood samples. Alpha diversity metrics and multivariate community analyses were applied, with correlation analyses linking microbiome indices to immune parameters. Results showed significantly reduced gut microbial diversity in HIV-positive children, with loss of Bifidobacterium and Lactobacillus species and expansion of potentially pathogenic Proteobacteria. Microbial diversity correlated positively with CD4 count and immunoglobulin G. Viral suppression was associated with partial microbiome restoration. This study provides preliminary evidence for gut-immune axis disruption in HIV-infected Nigerian children, addressing a significant evidence gap. Probiotic adjunct therapy and dietary microbiome support are proposed for future interventional investigation. Keywords: gut microbiome, HIV, immune function, CD4 count, paediatric Abuja.