Evaluation of HLA Class I and HLA Class II Allele Profile and Its Relationship with Clinical Features in Patients with Alopecia Areata: A Case-Control Study.

BACKGROUND: Alopecia areata (AA) is an autoimmune disease where autoimmune dysregulations along with genetic susceptibility are hypothesized to play a role in pathogenesis.

OBJECTIVE: The aim of this study in to evaluate HLA-A, HLA-B, HLA-C, HLA-DQB1 and HLA-DRB1 profile and its relationship with clinical features in AA patients.

MATERIALS AND METHODS: Ninety-eight patients with AA and 100 healthy controls were included in the study. HLA-A, HLA-B, HLA-C, HLA-DQB1 and HLA-DRB1 frequencies were analyzed using polymerase chain reaction-sequence specific primers (PCR-SSP).

RESULTS: HLA-B*39 and HLA-HLA-DRB1*15 allele frequencies were increased (p = 0.022 and p = 0.023, respectively), HLA-A*11 and HLA-B*35 frequencies were decreased (p = 0.006 and p = 0.014, respectively) in AA patients. HLA-B*13 and HLA-DRB1*11 were associated with poor prognostic factors. A class I allele, HLA-B*13 was associated with recurrence (p = 0.023) and presence of nevus flammeus (p = 0.022), while the class II allele HLA-DRB1*11 was associated with widespread hair loss (diffuse or universal alopecia) (p = 0.026), presence of ophiasis (p = 0.049) and juvenile onset (p = 0.018).

CONCLUSION: Belonging to two different classes of HLA family, HLA-B*13 and HLA-DRB1*11 alleles identified separate set of risk factors. In addition to increasing the risk of AA, HLA alleles may affect the prognosis of the disease.