HLA DRB1* and DQB1* alleles are associated with disease severity in patients with pemphigus vulgaris

Pemphigus vulgaris (PV) is a rare autoimmune disease that involves the skin and mucosa. The etiology of PV is multifactorial and includes genetic, environmental, hormonal, and immunological factors.

The purpose of this study was to examine the relationships between human leukocyte antigen (HLA) class II alleles associated with PV and variations in the disease phenotype.

Forty-four PV patients were diagnosed and analyzed at the Bullous Disorders Unit in cooperation with the Institute of Immunology, Faculty of Medicine, Comenius University, Bratislava, Slovakia. HLA class II alleles previously found to be associated with PV (DRB1*04:02, DRB1*04:04, DRB1*14:54, DRB1*14:04, DRB1*14:05, DQB1*03:02 and DQB1*05:03) were analyzed according to disease severity, PV type, and gender distribution.

Correlations emerged between PV severity scores and HLA alleles. The DRB1*04:02 and DQB1*03:02 alleles were associated with severe PV (P = 0.001); DRB1*04:02 was associated with the mucocutaneous type (P = 0.024), and DQB1*03:02 was found more frequently in female than in male patients (P = 0.016). Analyses of the other alleles did not reveal significant associations with the clinical parameters evaluated.

The HLA DRB1* and DQB1* alleles influence susceptibility to PV and may contribute to PV severity and type. These results suggest that genetic background may contribute to disease outcome by affecting the disease course and efficacy of treatment because some of the alleles were found significantly more frequently in patients with severe disease.