Objective: To investigate the implications of the HLA-B locus in the susceptibility to Henoch-Schönlein purpura (HSP) and determine if there are associations with renal and gastrointestinal (GI) manifestations of the disease.
Methods: A retrospective study was performed on an unselected population of patients with HSP from Northwest Spain. Forty-eight Caucasian patients (24 women), 11 of them older than 20 years, were studied. Patients and ethnically matched controls were HLA-B genotyped from DNA using molecular based methods.
Results: When patients with HSP were compared with matched controls, no differences in HLA-B frequencies were observed. No HLA-B associations with GI manifestations were observed. In contrast, an increased frequency of HLA-B35 was observed in patients with renal manifestations (10 of 31) compared to those without (0 of 17). No significant distortions in frequency were seen for any other HLA-B alleles with HSP subgroups.
Conclusion: Our results support a role of HLA-B35 in the susceptibility for nephritis in unselected patients with HSP.