CUTANEOUS HYPERSENSITIVITY REACTIONS TO THIACETAZONE, HIV-INFECTION AND THIACETAZONE CONCENTRATIONS IN PLASMA

We have studied the relationship between the plasma concentration-time profile of thiacetazone over the 24 h between doses [AUC(0,24h)] and the incidence of cutaneous reactions among HIV-infected patients with tuberculosis in Kenya. Cutaneous reactions due to thiacetazone occurre d in 4/14 [28.6%] HIV + ve patients compared with 3/47 [6.4%] HIV-ve p atients [RR = 4.48, 95% CI-1.1 to [17.7], and all resolved on alternat ive therapy. Among the HIV + ve patients, those with cutaneous reactio ns had higher AUC(0,24h) values, although the difference was not signi ficant. These results do not exclude pharmacokinetic change as being a t least partly responsible for cutaneous reactions to TCZ in HIV + ve patients, and do not refute an immunological basis for the reaction. W ith regard to the operational use of TCZ in Africa, there is no indica tion that a modification of the dose will reduce the frequency of drug reactions.