skip to main content

Monoarthritis in RA — SCE Rheumatology MCQ

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

ModerateRheumatoid arthritisMonoarthritis in RASCE Rheumatology

A 57-year-old man with established RA presents with a single swollen ankle after increasing prednisolone. Examination shows the joint is hot and very tender. Investigations show temperature is 38.1°C and CRP has risen from 12 to 96 mg/L. What is the most appropriate investigation?

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

Reveal the answer and explanation

Correct answer: D — Urgent synovial fluid microscopy, culture and crystal analysis

Acute monoarthritis in an immunosuppressed RA patient requires aspiration for infection and crystals. RF or anti-CCP titres do not distinguish flare from septic arthritis. A septic joint can coexist with chronic inflammatory arthritis and must be excluded before steroid injection.

Reference: NICE NG100; BSR biologic DMARD safety guideline; BNF