HLA AND SUSCEPTIBILITY TO 2 DISTINCT TYPES OF DRUG-INDUCED CUTANEOUS REACTIONS

The purpose of this work was to investigate HLA predisposition in two types of cutaneous drug reactions, which involve type IV hypersensitiv ity: maculopapular papular rash, a common clinical form, and acute gen eralized exanthematous pustulosis, a rare form. The frequency of the D RB11301 DQB1*0603 haplotype was increased in the maculopapular rash ( 17.5% versus 6.4% in the control, relative risk (RR) = 3.7), whereas t he HLA-B51(5) phenotype was increased in acute generalized exanthemato us pustulosis (46.7% versus 14.6%, RR = 5.1); but the differences were not significant after correction for the p value. The culprit drugs w ere stratified in three categories: pristinamycin, other antibiotics a nd non-antibiotics: no HLA association could be established with the c ulprit drugs. DRB101 allele frequency was decreased in both types of cutaneous drug reactions, suggesting that this allele could confer a p rotective effect to the both types. Although these results suggest a H LA predisposition to cutaneous drug reaction, they need to be validate d on a larger sample of patients.