Before prescribing carbamazepine to a 26-year-old woman of Han Chinese ethnicity for trigeminal neuralgia, which pharmacogenetic screening test is recommended to prevent Stevens-Johnson syndrome and toxic epidermal necrolysis?
- A HLA-A*31:01 typing
- B HLA-B*57:01 typing
- C HLA-B*15:02 typing ✓
- D HLA-B*58:01 typing
Correct answer: C. HLA-B*15:02 typing
Explanation
HLA-B*15:02 is strongly associated with carbamazepine-induced SJS/TEN in Han Chinese and other Southeast Asian populations, and regulatory bodies recommend screening before prescribing. The distractors are all real pharmacogenetic markers, which makes this genuinely discriminating: HLA-B*57:01 predicts abacavir hypersensitivity, HLA-B*58:01 predicts allopurinol-induced severe cutaneous reactions, and HLA-A*31:01 associates with carbamazepine-induced maculopapular exanthem and DRESS, not SJS/TEN.
Reference: Fitzpatrick's Dermatology, 9th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.