Polymorphismes génétiques et allergies médicamenteuses

Ten-to-twenty percent of hospitalised patients experience secondary drug reactions, and a third of these reactions may be allergic in nature. Multiple immune mechanisms may be at the base of these reactions. Antibiotics (especially β-lactams) are the principle type of drugs concerned, and they most often induce IgE-mediated allergic reactions. Information on the risk factors for drug allergies is limited, and few studies on genetic polymorphisms have been reported, except those involving certain enzymes that participate in drug metabolism or those concerning certain HLA haplotypes. Data coming from immunogenetic investigations should result in new diagnostic tools and, certainly, in better prediction of these events. Nevertheless, the results of such studies will vary depending on the population involved. Identification of genetic markers that are sufficiently predictive in clinical practice is going to require screening of hundreds of single nucleotide polymorphisms in the genome to be able to identify the subpopulation of patients that are at risk for each class of drugs.