HLA-DRB1 and pemphigus: Methods PubMed, Wiley Online Library, ScienceDirect, Google Scholar, Cochrane Library, Chinese National Knowledge Infrastructure and Wanfang databases were searched for studies including: (i) ‘pemphigus’; and (ii) ‘human leukocyte antigen’, ‘HLA’, ‘major histocompatibility complex’, ‘MHC’ or ‘DRB1’.