When each group was stratified according to CD4+ T-cell count, it was found that cavitation was significantly less common in those HIV-infected persons with CD4+ T-cell counts < 200 cells/μL than those with CD4+ T-cell counts ≥ 200 cells/μl, in both the TB group (10.86 vs 33.33%) and the non-TB group (2.55 vs 5.56%). Here, CD4 is linked to tuberculosis.