High prevalence of previously undiagnosed axial spondyloarthritis in patients referred with anterior uveitis and chronic back pain - the SpEYE study

Objective To reduce the diagnostic delay in axial spondyloarthritis (axSpA), guidelines recommend to refer patients with acute anterior uveitis (AAU) and chronic back pain (CBP) to a rheumatologist. This observational study evaluated the prevalence of previously unrecognized axSpA in AAU patients with CBP in daily practice, referred by ophthalmologists who had received instructions to increase awareness.

Methods All AAU patients referred with CBP (≥3 months, started <45 years of age), from five Ophthalmology clinics underwent rheumatologic assessment, including pelvic X-rays. Patients with previously diagnosed rheumatic disease and established other cause of AAU were excluded. The primary endpoint was a clinical axSpA diagnosis by the rheumatologist.

Results Eighty-one patients fulfilled the referral criteria (52% male, 56% HLA-B27 positive, median age 41 years, median CBP duration 10 years). In total, 58% (n=47) had recurring AAU, of whom 87% already had CBP during previous AAU attacks. After assessment, 23% (n=19) of patients were clinically diagnosed with definite-axSpA (10/19 radiographic), 40% (n=32) were suspicious of axSpA and 37% (n=30) did not have axSpA. AxSpA was diagnosed more often in men (33% of the men versus 13% of women).

Conclusion A high prevalence of axSpA was found in AAU patients referred because of CBP. There was substantial diagnostic delay in the majority of patients with recurring AAU, as many already had back pain during previous AAU flares. In AAU, screening for CBP and prompt referral has a high diagnostic yield, and should consistently be promoted among ophthalmologists.