Correlation Between HLA Allele and Drug Patch Test Result in Cutaneous Adverse Drug Reactions
Rujira Leetanaporn, Supharat Suvichapanich, Punna Kunhapan, Surakameth Mahasirimongkol, Supitchaya ThaiwatBackground
Drug patch testing was affected by multiple influencing factors. HLA allele‐associated drug allergy was mentioned as one factor influencing drug patch testing. We aimed to evaluate the correlation between drug patch test and HLA alleles in patients with cutaneous adverse drug reactions.
Methods
The study enrolled 30 patients, who had drug patch testing, to evaluate HLA alleles. We compared HLA alleles between patients with positive and negative patch test results and between those with positive patch tests and the Thai general population.
Results
Among the 30 patients, including 20 positive patch test patients and 10 negative‐patch test patients, a distribution for males (50%) was observed, with a mean age of 55.4 ± 15.5. The most prevalent cutaneous drug reactions in patch test‐positive patients were morbilliform drug eruption 8/20 (40.0%) and fixed drug eruption 7/20 (35.0%). NSAIDs and antibiotics were the dominant culprit drug groups. These groups account for 5/20 (25.0%) and 4/20 (20.0%) of patients, respectively. None of the HLA alleles was significantly identified in patients with positive patch test compared to patients with negative patch test. However, HLA‐B ∗ 54:01 and HLA‐C ∗ 07:01 were significantly associated with patients who had positive patch test results for NSAID‐induced minor drug reactions when compared with the Thai general population ( p ≤ 0.0001), with odds ratios of 34 and 10, respectively.
Conclusion
In this small pilot study, HLA‐B ∗ 54:01 and HLA‐C ∗ 07:01 alleles showed a preliminary association with positive patch test results in patients with NSAID‐induced minor drug reactions. We hypothesized that HLA alleles might influence the positive patch test reaction.