Setting: Severe skin reactions due to thiacetazone (T) in Human Immunodeficiency Virus (HIV) positive tuberculosis patients have been reported in several publications, one of them from Kenya. However, the abandoning of T may not be feasible in Kenya as this may increase the cost of drugs by about three-fold per regimen.
Objective: To compare the cost-effectiveness and total cost of three strategies in which T is replaced with ethambutol (E).
Design: Three strategies are compared with a baseline strategy in which T is not replaced. The indicator for cost-effectiveness is the cost-per-averted-death attributable to T.
Results: Education of patients on the possibility of side-effects and replacement of T with E is the most cost-effective strategy at HIV prevalence rates of 1-90%. Abandonment of T and replacement with E is the most cost-effective at over 90% HIV prevalence.
Conclusion: In Kenya, education of patients on the possibility of skin reactions should be preferred at low range HIV prevalence rates. Routine HIV testing would be the most attractive strategy in the middle range, and total replacement of T with E is to be preferred in the higher range of HIV prevalence.
PIP: In Kenya, the National Leprosy Tuberculosis Programme (NLTP) used previously reported data from Nairobi to compare the cost-effectiveness and total costs of a hypothetical strategy with three intervention strategies for the prevention and management of severe skin reactions caused by thiacetazone in treating HIV-positive patients with tuberculosis (TB). The hypothetical strategy was continued use of thiacetazone despite adverse skin reactions. The intervention strategies included patient education about possible side effects of anti-TB drugs (discontinue use if skin rash develops, report situation to clinic, replace thiacetazone with ethambutol when other skin diseases have been excluded), abandonment of thiacetazone and replacement with ethambutol, and HIV testing and pre- and post-test counseling. NLTP currently used the education strategy. It assumed a mortality rate of 5%. When the HIV prevalence rate is 1-90%, the education strategy is the most cost-effective strategy. In terms of total costs, the education strategy was also the most inexpensive strategy regardless of the HIV prevalence. At an HIV prevalence rate greater than 65%, the abandonment of thiacetazone strategy was the cheapest strategy. When the assumed mortality rate was 3%, the cost per averted death for the education strategy was reduced from about US$120 to about US$80 and the education strategy became the most cost-effective strategy over the entire range of HIV prevalence. In addition, the cost of HIV testing significantly increased the cost per averted death. Thus, the findings of this study are truly sensitive to different program conditions. Based on these findings, the authors recommended that the education strategy be applied with a range of HIV prevalence of 1-45%, that HIV testing be applied with a range of 46-72%, and that total abandonment be applied with an HIV prevalence greater than 72%.