HLA-B 15:13 Positive in an Indonesian Patient with Phenytoin-Induced SJS/TEN

Steven-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are severe forms of delayed hypersensitivity reaction with an underlying immunologic mechanism involving the interaction between HLA and drug molecules. A-35-year-old Javanese-Indonesian-male, with a history of seizures, presented with skin peeling, mucosal erosions, and purulent eye discharges. He was clinically diagnosed as overlapping SJS/TEN, and both phenytoin and valproic acid became the suspected drugs. Unfortunately, the seizure relapsed and alternative antiepileptic drugs were urgently needed. HLA typing was then performed, revealing the presence of HLA-B*15:13, which has been proven to be correlated with phenytoin adverse reaction by previous study. Thus, phenytoin was totally discontinued and he only prescribed monotherapy valproic acid. Given the high prevalence and common use of phenytoin in clinical practice, HLA evaluation before phenytoin prescription in Indonesia is important. Further studies are recommended to provide more evidence regarding the role of HLA-B*15:13 in phenytoin-induced severe hypersensitivity reactions in Indonesia.