skip to main content

Non-radiographic axial spondyloarthritis — SCE Rheumatology MCQ

Instant feedback + full explanation. One question, done properly.

ModerateMusculoskeletal MedicineNon-radiographic axial spondyloarthritisSCE Rheumatology

A 33-year-old man is assessed for a 5-year history of low back pain that began before the age of 30 years. He wakes with pain during the second half of the night, has alternating buttock pain and improves with exercise but not rest. He has previously had two ophthalmologist-confirmed episodes of acute anterior uveitis and an episode of atraumatic Achilles enthesitis. Examination shows reduced lumbar flexion but no peripheral synovitis. C-reactive protein and erythrocyte sedimentation rate are normal, and HLA-B27 is positive. Plain radiographs of the sacroiliac joints do not meet the modified New York criteria for sacroiliitis. An unenhanced MRI, including T1-weighted and STIR sequences of the sacroiliac joints and whole spine, does not meet ASAS/OMERACT criteria. Specialist musculoskeletal radiology review confirms the MRI interpretation and identifies no alternative cause for his symptoms. Which is the most appropriate diagnostic action now?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: B — Record a diagnosis of non-radiographic axial spondyloarthritis

Explanation lettering: C = shown as A · D = shown as B · E = shown as C · B = shown as D · A = shown as E

This presentation supports non-radiographic axial spondyloarthritis through the clinical arm of the ASAS framework: he is HLA-B27 positive and has multiple spondyloarthritis features, including inflammatory back pain, acute anterior uveitis and enthesitis. NICE states that a negative MRI does not exclude axial spondyloarthritis and, when HLA-B27 is positive, the diagnosis may be based on clinical features. Normal inflammatory markers are also non-exclusionary. A is incorrect because radiographic axial spondyloarthritis requires sacroiliitis meeting modified New York criteria on plain radiographs, which is absent. B gives excessive weight to normal inflammatory markers and negative imaging despite a strongly concordant clinical phenotype. C is unnecessary because the protocol-compliant MRI has already undergone specialist musculoskeletal radiology review. E is a plausible near-miss: NICE advises considering follow-up MRI when the diagnosis cannot be confirmed and suspicion remains high. Here, however, the positive HLA-B27 result and multiple characteristic clinical features permit a clinical diagnosis, so repeating MRI is not a prerequisite.

Reference: Spondyloarthritis in over 16s: diagnosis and management — Recommendations (Published 28 February 2017) — https://www.nice.org.uk/guidance/ng65/chapter/Recommendations