Cost-effectiveness of including tuberculin skin testing in an IPT program for HIV-infected persons in Uganda

SETTING: Tuberculosis (TB) is the most common opportunistic infection among persons with human immunodeficiency virus or the acquired immune-deficiency syndrome (HIV/AIDS). Isoniazid preventive therapy (IPT) effectively treats latent TB infection (LTBI) and prevents progression to active TB.

OBJECTIVE: To analyse the costs and cost-effectiveness of tuberculin skin testing (TST) prior to offering IPT.

DESIGN: We implemented a program for LTBI screening and IPT using TST for persons with HIV at a voluntary counseling and testing (VCT) center in Kampala, Uganda. Cost-effectiveness analyses using Markov methods were adopted to compare strategies of using and not using TST before offering IPT.

RESULTS: The program enrolled 7073 persons with HIV. Based on the prevalence of LTBI in the population, 34/100 HIV-infected patients would benefit from IPT. The results showed that 28% of LTBI patients would be treated using the TST strategy, and 40% would be treated with a non-TST strategy. Compared to no intervention, the estimated incremental cost of identifying and providing IPT using TST was $211 per patient; the incremental cost using a non-TST strategy was $768 per patient.

CONCLUSION: At a large VCT center in Uganda, the inclusion of TST to identify the HIV-infected persons who will most benefit from IPT is cost-effective.