Complete remission of refractory pemphigus vulgaris in a Chinese patient with mutated NUDT15 by combination of minimal doses of azathioprine and prednisone.

Although azathioprine (AZA) combined with corticosteroids remains the first-line therapy to treat patients with pemphigus vulgaris (PV), there are increasing reports of AZA-induced leukopenia, which provides the rationale for monitoring the blood cell count and testing the genotypes at the thiopurine methyltransferase (TPMT) and the nucleoside diphosphate-linked moiety X-type motif 15 (NUDT15) genes. Here, we reported a case of persistent refractory PV in a Chinese patient with three runs of AZA-corticosteroids treatment. In the first two runs he received AZA-corticosteroids at standard or slightly reduced doses and developed leukopenia.