CD4 cell count recovery in HIV/TB co-infected patients versus TB uninfected HIV patients

There is lack of data comparing the improvement in CD4 count following antitubercular (ATT) and antiretroviral therapy (ART) in patients presenting with Human Immunodeficiency Virus/Tuberculosis (HIV/TB) dual infection compared with CD4 matched cohort of TB uninfected HIV patients initiated on ART. We sought to test the hypothesis; TB additionally contributes to reduction in CD4 count in HIV/TB co-infected patients and this would result in greater improvement in count following treatment compared with CD4 matched TB uninfected individuals.

In a retrospective cohort study design we studied the change in CD4 cell counts in two groups of patients - those with CD4 cell count >100 cells / mm 3 (Group 1) and <100/mm 3 (Group 2) at presentation. In each group the change in CD4 cell count in dually infected patients following six-month ATT and ART was compared to cohorts of CD4 matched TB uninfected patients initiated on ART.

In Group 1 (52 patients) dually infected subjects' CD4 count improved from 150 cells/ mm 3 to 345 cells/mm 3 (P=0.001). In the control TB uninfected patients, the change was from 159 cells/mm 3 to 317 cells/mm 3 (P=0.001). Additional improvement in dually infected patients compared to the control group was not statistically significant (P=0.24). In Group 2 (65 patients) dually infected subjects count improved from 49 cells/mm3 to 249 cells/mm 3 (P=0.001) where as in control TB uninfected patients improvement was from 50 cells/ mm 3 to 205 cells/mm 3 (P=0.001), there being statistically significant additional improvement in dually infected subjects (P=0.01).

Greater increment in CD4 counts with ATT and ART in dually infected patients suggests that TB additionally influences the reduction of CD4 counts in HIV patients.