HLA-DRB1*01 association with Henoch-Schonlein purpura in patients from northwest Spain

Objective. To examine the HLA-DRB1 phenotypes of patients with Henoch-Schon lein purpura (HSP) and determine if associations exist with disease suscept ibility, clinical heterogeneity, or severe systemic complications. Methods. A retrospective study was performed on an unselected population of patients from Northwest Spain with HSP classified according to proposed cr iteria. Patients were included in this study if they had at least one year of followup. Fifty Caucasian patients (25 women), 11 of them older than 20 years, were studied. Patients and ethnically matched controls were HLA-DRB1 genotyped from DNA using molecular based methods. Results, During the course of the disease, renal manifestations, especially hematuria, and severe gastrointestinal (GI) manifestations (bowel angina o r GI bleeding) were observed in more than 60% of the patients. Twenty perce nt of patients had persistent renal involvement (renal sequelae). Patients with HSP had a significantly higher frequency of the HLA-DRB1*01 phenotype compared to matched controls. The HLA-DRB1*07 phenotype was also significan tly reduced compared with controls. Patients with severe GI manifestations or with persistent renal involvement did not exhibit any specific HLA-DRB1 association other than the underlying association with HLA-DRB1*01. Conclusion. HSP in a population from Northwest Spain is significantly assoc iated with HLA-DRB1*01.