Association of HLA subtype DRB10407 in Colombian patients with actinic prurigo.

BACKGROUND

Human leukocyte antigen (HLA) DRB1*0407 had been associated with actinic prurigo in different populations. This class II HLA-DR subtype had not been studied in Colombia.

OBJECTIVE

The objective of this study was to establish whether there was an association of actinic prurigo with HLA DR in a Colombian population.

MATERIALS AND METHODS

Forty patients with a clinical diagnosis of actinic prurigo and 40 healthy subjects, paired by age, sex and birthplace, were studied. HLA typing for HLA DRB1 and DRB1*04, if necessary, was performed by the PCR-SSP method using blood samples.

RESULTS

A high frequency of HLA DRB10407 was found in the patients (97.5% vs. 30%; P<0.00001). The allelic frequency of HLA DRB10407 was 63.8% in the case group, and 14.5% in the controls (P<0.00001). In the control group, there was a higher frequency of the alleles DRB101 (14.5% vs. 1.25%; P=0.0027) and DRB113 (23.7% vs. 2.5%; P=0.00013).

LIMITATIONS

The small number of controls does not allow us to drive conclusions about other HLA alleles.

CONCLUSIONS

HLA subtype DRB10407, found in actinic prurigo patients in studies conducted in England, Scotland, Ireland and Mexico, was also associated in Colombian patients. This finding, concordant in patients from different ethnic groups, could be helpful in the diagnosis of this disease and probably important in its pathogenesis. DRB101 and DRB1*13 alleles were more frequent in controls than in patients; we do not know whether they play any role in the resistance to the disease.