Prevalence and Predictors of CD4+ T-Lymphocytopenia Among HIV-Negative Tuberculosis Patients in Uganda.

Purpose: CD4+ T-lymphocytopenia is a risk for tuberculosis (TB) infection, reactivation and severe disease. We sought to determine the prevalence and predictors of CD4 T-lymphocytopenia among HIV-negative patients with bacteriologically confirmed TB in Uganda.

Patients and methods: Eligible participants were adult HIV-negative patients with bacteriologically confirmed TB at the National TB Treatment Centre in Uganda. CD4+ and CD8+ T-lymphocyte counts were determined by flow cytometry. We defined CD4+ T-lymphocytopenia as a CD4+ T-lymphocyte count of <418 cells/mm³ as per the population estimate for Ugandans. We performed logistic regression analysis to determine predictors of CD4+ T-lymphocytopenia.

Results: We enrolled 216 participants whose mean age (standard deviation (±SD)) was 32.5 (±12.1) years, of whom 146 (67.6%) were males. The prevalence of CD4+ T-lymphocytopenia was 25% (54/216) (95% confidence interval (CI): 19.6-31.2%). Patients with anaemia (adjusted odds ratio (aOR): 3.83, 95% CI: 1.59-9.23, p = 0.003), weight loss (aOR: 3.61, 95% CI: 1.07-12.23, p = 0.039) and a low CD8+ T-cell count (aOR: 6.10, 95% CI: 2.68-13.89, p < 0.001) were more likely to have CD4+ T-lymphocytopenia while those with monocytosis (aOR: 0.35, 95% CI: 0.14-0.89, p = 0.028) were less likely to have CD4+ T-lymphocytopenia.

Conclusion: There was a high prevalence of CD4+ T-lymphocytopenia among HIV-negative TB patients. Patients with weight loss, anaemia and a low CD8+ count were more likely to have CD4+ T-lymphocytopenia while those with monocytosis were less likely to have CD4+ lymphocytopenia. The findings suggest that CD4+ lymphocytopenia is indicative of severe disease and globally impaired cell-mediated immune responses against TB.