HIV and Diarrhea: Clinical Characteristics and Etiology at a High-Complexity Center in Southwest Colombia.

Objective: Human immunodeficiency virus (HIV) infection remains highly prevalent and represents a significant economic burden on healthcare systems. The World Health Organization (WHO) reported 39 million people living with HIV (PLWH) in 2023. In Colombia, 185,954 prevalent cases were reported during 2024. Diarrhea affects up to 50% of PLWH. This study aimed primarily to estimate the prevalence of infectious versus noninfectious etiology of diarrhea among adults with HIV and to compare immunological and clinical events. Design/Method: Cross-sectional observational study included adult patients with HIV and diarrhea who received care at Fundación Valle del Lili between 2014 and 2022. Clinical variables, diarrhea etiology, treatment, and clinical events were analyzed according to the chronologic classification of diarrhea using chi-squared and F tests for qualitative variables and Kruskal-Wallis and ANOVA tests for quantitative variables. Effect sizes are reported as odds ratios (ORs) with 95% confidence intervals (CIs) for binary outcomes between infectious and noninfectious diarrhea. Limitations include the cross-sectional design, single-center setting, and convenience sampling. Results: Among the patients, 73.8% were male, and the mean age was 42 years. De novo diagnosis was made in 26.2% and 90.5% of previously diagnosed individuals receiving antiretroviral therapy. The 23% had AIDS-defining conditions. One-third of the patients had acute diarrhea. Infectious etiology was found in 65.5% of patients and was associated with higher viral loads and lower CD4 (+) T-cell counts compared to noninfectious diarrhea. Antibiotic therapy was used in 57%, and diarrhea had resolved in 77/84 (91.7%) by discharge. Associated mortality was 2.8%. Conclusions: The predominant cause of diarrhea was infectious. Infectious etiology and persistent diarrhea were associated with higher viral loads and lower CD4 (+) T-cell counts, which may be linked to poorer clinical outcomes in HIV-infected patients. Further studies are required to better understand these relationships.