Fecal Gram stain morphotype and their distribution patterns in a Cameroonian cohort with and without HIV infection

Targeting the gut microbiota in diagnosing diseases has recently gained interest in microbiome studies. Early and fast disease prognosis could be derived from Gram stain assessment of fecal flora distribution. Gram staining could guide the culturomics and sequencing approaches. The present study aimed at identifying fecal Gram stain morphotype and distribution patterns among HIV-negative and HIV-positive individuals, and assessing the associations of this flora with diet, CD4+ T cell count, and antiretroviral treatment; hence Gram stain was performed for all the stool samples. The study was carried out between August 2018 and February 2019. In this study, we recruited 213 participants, of which 108 were infected with HIV and 105 HIV-negative individuals without a known history of drugs consumption for the last 6 months as control. Findings revealed that the occurrence of a single pattern was significantly associated with age (p = 0.016) and diet (p = 0.012) between HIV-infected and HIV-negative individuals. Also, for the Gram stain fecal flora distribution count, the frequency of scanty pattern was significantly associated with age (p = 0.027) and the nature of drinks consumed (p = 0.039). Furthermore, the mean CD4+ T cell count was significantly higher in a diverse pattern (730 cells/mm3) compared to the depleted pattern (285 cell/mm3) (p = 0.015). HIV-negative individuals had a significant high Gram stain flora diverse pattern when compared to HIV-positive individuals and those on Antiretroviral treatment (ART) (p = 0.010). The Gram stain flora distribution among the participants showed a significant high abundance pattern among HIV-positive individuals on ART and HIV-negative individuals, compared to HIV-positive individuals who were not yet on ART (p = 0.0001). The Gram stain flora morphotype and distribution pattern decrease with the reduction of CD4+ T cell count and vice versa. Besides, we found that diet rich in energy-yielding and protective food, younger age participants and HAART were associated with Gram stain fecal flora distribution. Further works are warranted to ascertain these associations for possibilities of utilizing Gram fecal flora to infer immune status and better guide interpretation of patients’ prognosis in HIV condition.