Abstract
Purpose: :
A prospective longitudinal study with 5 years follow up of consecutive patients presenting with idiopathic intermediate uveitis (IIU).
Methods: :
The patients were derived from both secondary and tertiary referral centres to reduce selection bias. Any patient with a systemic condition known to be associated with IIU (eg sarcoidosis), or a local inflammatory disorder (eg choroiditis), or who developed these during the study period was excluded. Recorded baseline variables were sex, age at onset, and retinal ischaemia evident on fluorescein angiography. The primary outcome measure was possession of the HLA-DR15 allele. Molecular genotyping for the HLA-class II allele HLADR15 was performed by PCR amplification with sequence-specific primers (PCR-SSP) following extraction of genomic DNA from EDTA anti-coagulated blood. Visual acuity, which was assessed at 3 months and 5 years, was a secondary outcome measure.
Results: :
HLA typing was performed in 85 patients with IIU and 300 local, healthy, ethnically matched controls. The mean age of participants in the study was 41 years (range: 14 - 74 years), 64% were female and 97% were of White ethnicity. 71/85 (84%) of patients with IIU were HLA-DR15 positive compared to 90/300 (30%) of local controls (OR:11.83, 95%CI 6.3- 22.1,p= 0.05). There was no significant association between possession of the HLA-DR15 allele and visual acuity. A total of 67 (79%) patients maintained good vision of 6/12 or better in at least one eye at the time of their final assessment regardless of their HLA-DR15 status. In the HLA-DR15 positive group 55/71(78%) of patients maintained good visual acuity at 5 years follow up. Good visual acuity at 5 years follow up was maintained by 12/14 (86%) patients who did not possess the HLA-DR15 allele (OR:0.58, 95%CI 0.16 - 2.8). Visual outcome showed a trend when comparisons were made between vision at 3 months (x2=0.67) and 5years (x2=0.80) in that patients who possessed good visual acuity at entry into the study tended to maintain good vision at 5-year and patients with poor vision at entry into the study demonstrated poor vision throughout.
Conclusions: :
HLA-DR15 was associated with IIU but was not associated with a worse visual outcome.
Keywords: inflammation • autoimmune disease • uvea