[Placebo-controlled graded oral penicillin challenge in low-risk patients living with HIV without prior skin testing]

To evaluate the single-blind, placebo-controlled penicillin challenge in HIV/AIDS patients without prior skin testing.

A prospective study was conducted in patients attending the Outpatient Center for the Prevention and Care of AIDS and Sexually Transmitted Infections in Puebla, Mexico. Statistical analysis included percentages, frequencies, means, standard deviations, and medians; χ² (Fisher's exact test), one-way Kruskal-Wallis test, Cramer's V test; and binomial distribution. The Statistical Package for the Social Sciences 26 (SPSS) was used for data analysis.

A total of 104 patients aged 18 years or older (mean age 34.6 ± 10.5 years) were registered: women (n = 3; 2.9%), men (n = 101; 97.1%). Regarding the study variables, the following results were found: 7 (6.7%) positive penicillin challenges, 2 (1.9%) positive placebo challenges, and 95 (91.3%) no reaction; effect size V = 0.038, p = 0.701 (placebo-penicillin), V = 1, p = 0.000 (no reaction-penicillin reaction), with a binomial distribution and B(7; 0.1533). Regarding comorbidities, a difference was observed between the groups (p<0.05) in symptoms during the challenge: pruritus in the penicillin reaction group (p = 0.03) and anxiety in the placebo group (p = 0.005).

In HIV/AIDS patients categorized as low risk, the single-blind, placebo-controlled penicillin challenge allowed for the elimination of potential allergy, because the benefit of the antibiotic is crucial for a successful disease outcome.