Clinical Utility of HLA-B*58:01 Genotyping to Prevent Allopurinol-Induced SJS/TEN

Purpose: A 28-year-old male reported to our hospital with Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) overlap syndrome that developed as an adverse drug reaction (ADR) to allopurinol. HLA-B*58:01 allele is associated with an increased risk of developing allopurinol-induced SJS/TEN. Methods: Genomic DNA was extracted from peripheral blood leukocytes. DNA sequencing was done using SANGER sequencing method. Results: Pharmacogenetic testing results revealed positive for HLA-B*58:01 allele. Symptoms of the patient receded after allopurinol withdrawal. Conclusion: The thrust of personalized therapy is from decoding the individual specific genetic variations astutely for better therapeutic outcomes such as reducing the ADRs. Pharmacogenetic testing is emerging as a safe, fast, and economic screening tool for personalized therapy by preventing ADRs. Pharmacogenetic HLA-B*58:01 allele testing before allopurinol administration could significantly reduce the incidence of SJS/TEN and associated mortalities/morbidities and thereby represent a potential cost-effective intervention.