Reactive arthritis

• Asymmetric oligoarthritis (knees, ankles), sacroiliitis, enthesitis, dactylitis; urethritis, cervicitis, circinate balanitis; conjunctivitis or uveitis; oral ulcers, keratoderma blennorrhagicum.

• Investigations: ESR/CRP, CBC, urine/genital chlamydia PCR, stool culture, HLA-B27, joint aspiration (sterile fluid – exclude septic arthritis).

Management

• Rest in the acute phase, physiotherapy, condom use, nutritional support, education (usually self-limiting).

NSAIDs (first-line)

• A: Ibuprofen (PO) 400–800 mg every 8 hours,

• OR C: diclofenac (PO) 50 mg every 8–12 hours (or diclofenac gel 1% every 6 hours),

• OR A: piroxicam (PO) 20 mg once daily, OR D: meloxicam (PO) 7.5–15 mg once daily,

• OR S: ketoprofen (PO) 75 mg every 8 hours (or ketoprofen gel 2.5% every 6 hours).

• Add a PPI when the risk of NSAID gastrointestinal complications is high.

• S: Dexketoprofen (PO) 25 mg every 8 hours is an alternative.

• Glucocorticoids: A: prednisolone (PO) 5–10 mg once daily (short course), OR S: triamcinolone acetonide 10–40 mg deep IM monthly or 20–40 mg intra-articular.

• Antibiotic only with ongoing infection (especially Chlamydia): A: doxycycline (PO) 100 mg every 12 hours for 7–14 days.

• Chronic or refractory (arthritis over 3–6 months): D: sulfasalazine (PO) 500 mg every 12 hours, increased by 500 mg weekly to 2–3 g/day in divided doses, OR S: Methotrexate (PO) 15–25 mg once weekly AND A: folic acid (PO) 5 mg weekly (not on the methotrexate day).