HLA-B and Scarring: Further investigated the cross-reactivity of dapsone and other sulfa drugs in 6 dapsone-induced SCAR patients carried HLA-B*13:01, the result showed that dapsone-induced SCAR patients carried HLA-B*13:01 had a high cross-reactivity to sulfasalazine and sulfamethoxazole (sensitivity 66.7% and 83.3%, respectively), but not to probenecid, gliclazide and glimepiride (Additional file 2: Fig. S3A and B).