Frequency of class 1 human leukocyte antigen allele subtypes in Egyptian patients with idiopathic uveitis

Bacground Idiopathic uveitis is the most common uveitis type and is viewed as an inconclusive diagnosis for patients as well as physicians. Human leukocyte antigen (HLA) typing helps in understanding the pathogenesis of several diseases. Limited knowledge is known regarding the association of HLA with idiopathic uveitis. Aim This was a cross-sectional observational case-control study evaluating HLA-A and HLA-B allelic and phenotypic frequencies in patients with idiopathic uveitis. Patients and methods HLA-A and HLA-B molecular typing by PCR-sequence-specific oligonucleotide probes and LIRAS interpretation software was performed for 60 patients with idiopathic uveitis and 60 controls recruited from Kasr Al-Ainy Hospitals, Cairo University. Results Anterior uveitis pattern was the most common (55%), followed by pan-uveitis (35%) and posterior uveitis (10%). Overall, 40% of patients had bilateral uveitis, whereas 60% had unilateral uveitis. A total of 23 HLA-A and 43 HLA-B variant alleles were detected. HLA-A*09 and HLA-AFNx0110 allele and phenotype frequencies were significantly higher in the patient group (P=0.023 and 0.034, and P=0.013 and 0.029, respectively). HLA-B*07 allele and phenotype frequencies were significantly higher in the control group (P=0.007 and 0.006, respectively). HLA-B*27 and HLA-B*05 were detected in 8.3 and 26.7%, respectively, with no significant difference. Conclusion HLA-A*09 and HLA-A*10 alleles were statistically significantly higher in patients with idiopathic uveitis. HLA-B*07 might be a protective allele against disease development. Larger cohort needs to be tested to validate these findings. Routine HLA typing and proper follow-up for primarily diagnosed idiopathic uveitis is recommended as it might reveal secondary causes for uveitis, especially in patients with positive HLA-B*27 and HLA-B*05.