The beneficial effects of adjunctive recombinant human interleukin-2 for multidrug resistant tuberculosis

INTRODUCTION: Multidrug-resistant tuberculosis (MDR-TB) is a hard-to-treat disease with a poor outcome of chemotherapy. In the present study, the efficacy and safety of recombinant human interleukin-2 (rhIL-2) were investigated in patients with MDR-TB. MATERIAL AND METHODS: Fifty culture-confirmed patients with MDR-TB were included. Twenty-five patients were randomly assigned to the trial group (injection of 500 000 IU of rhIL-2 once every other day at the first, third, fifth and seventh months in addition to standard multidrug therapy) and another 25 patients to the control group with standard multidrug therapy. All patients were monitored clinically, and T-cell subsets were analyzed by flow cytometry. RESULTS: The rates of sputum negative conversion and X-ray resolution in the trial group were higher than those of the control, and the improvements were significant by completion of treatment. In addition, CD4(+)CD25(+) T cells in the controls rose gradually during treatment. The levels at the end of the seventh month were significantly higher than before, which were also significantly different when compared with those from the trial group at the same time. However, there were no such changes associated with treatment in the trial group. No significant differences appeared in other T cell subsets. CONCLUSIONS: Exogenous IL-2 in the present regimen improves immunity status. Adjunctive immunotherapy with a long period of rhIL-2 is a promising treatment modality for MDR-TB.