OR5.1 | Inflammatory Arthritis — Graded Quiz

Correct. Methotrexate (anchor DMARD) combined with hydroxychloroquine forms a standard csDMARD combination for RA. Long-term steroids alone are avoided due to adverse effects.

Methotrexate is the anchor DMARD in RA and is used as first-line in a treat-to-target strategy. For moderate-to-severe disease, combination csDMARD therapy (MTX + hydroxychloroquine + sulfasalazine — 'triple therapy') or MTX + a biologic (TNF inhibitor) is recommended if targets are not met at 3-6 months.

RA requires DMARDs — colchicine/indomethacin are for gout; allopurinol is urate-lowering; long-term steroids alone are inappropriate as they cause bone loss, infection, and diabetes.

Correct. NSAIDs are first-line for axial AS, providing both analgesia and a possible disease-modifying effect on radiographic progression. Physiotherapy is essential to maintain spinal mobility.

NSAIDs (e.g., naproxen, diclofenac, indomethacin) are first-line for axial spondyloarthritis/ankylosing spondylitis, providing both pain relief and possibly slowing radiographic progression. Physiotherapy is concurrent. DMARDs (e.g., sulfasalazine) are used for peripheral joint involvement; biologics (anti-TNF, anti-IL-17) are second line.

For axial AS, NSAIDs are the first-line pharmacological treatment. Methotrexate and hydroxychloroquine are ineffective for axial disease. High-dose steroids are not appropriate long-term.

Correct. Psoriasis + dactylitis + DIP joint involvement + pencil-in-cup deformity + seronegative = psoriatic arthritis.

Psoriatic arthritis: seronegative (RF/anti-CCP negative), associated with psoriasis, characteristically involves DIP joints (unlike RA which spares DIPs), causes dactylitis (sausage digit), and the pencil-in-cup deformity on X-ray indicates arthritis mutilans — osteolysis of the terminal phalanx head into the cupped base of the middle phalanx.

Seronegative RA typically spares DIP joints and does not cause dactylitis or pencil-in-cup deformity. Gout presents with tophi and crystal arthritis. Reactive arthritis follows an infection.

Correct. C1-C2 instability with cord compression in RA requires immediate immobilisation with a rigid cervical collar and urgent surgical referral for posterior fusion.

Atlanto-axial subluxation (C1-C2 instability due to pannus erosion of the transverse ligament and odontoid peg in RA) with myelopathy requires urgent surgical stabilisation — typically posterior C1-C2 fusion. This is a serious extra-articular/spinal complication of RA that must be recognised.

Atlanto-axial subluxation with myelopathy is a surgical emergency in RA. NSAIDs are inadequate; MTX dose increase will not protect the cord; C1-C2 steroid injection is not appropriate for an unstable spine.

Correct. Anti-TNF agents are the primary biologic class for active AS failing NSAIDs. Anti-IL-17A (secukinumab) is also approved as an alternative.

Anti-TNF agents (adalimumab, etanercept, infliximab, certolizumab) and anti-IL-17A agents (secukinumab, ixekizumab) are the approved biologics for active ankylosing spondylitis failing NSAIDs. Anti-TNF is the most established second-line biologic class.

Tocilizumab (anti-IL-6) is ineffective for axial AS. Rituximab (anti-CD20) and abatacept (CTLA4-Ig) are used in RA, not AS.

Correct. OA is characterised by brief stiffness (<30 min), mechanical worsening, normal/near-normal ESR, and X-ray features of osteophytes/sclerosis without erosions — the reverse of inflammatory arthritis.

Osteoarthritis (OA) vs inflammatory arthritis: OA shows brief morning stiffness (<30 min), normal or mildly elevated inflammatory markers, and radiological features of joint space narrowing + osteophytes + subchondral sclerosis — opposite of inflammatory arthritis (erosions, periarticular osteoporosis, elevated ESR/CRP, prolonged morning stiffness >1 hour).

The ESR of 18 mm/hr (near normal), brief stiffness, and X-ray showing osteophytes/sclerosis without erosions all point to OA. Inflammatory arthritis would show elevated ESR/CRP, prolonged morning stiffness, and X-ray erosions.

Correct. Methotrexate is a category X teratogen — it must be stopped at least 3 months (some guidelines say 1-3 months) before conception. Hydroxychloroquine and sulfasalazine are compatible with pregnancy.

Methotrexate is an absolute contraindication in pregnancy — it is a folate antagonist and causes miscarriage, major structural malformations, and fetal death. It must be stopped at least 3 months before conception. Hydroxychloroquine and sulfasalazine are generally considered safe in pregnancy and can be continued.

Methotrexate is absolutely contraindicated in pregnancy at any dose. It is a known teratogen causing aminopterin syndrome. It must be stopped well before conception, and RA should be managed with pregnancy-compatible DMARDs.

Correct. The ankylosed AS spine is at high risk for fracture after minimal trauma — CT is mandatory even with a normal X-ray; MRI is added if neurological deficit is confirmed.

In ankylosing spondylitis, the rigid ankylosed spine is highly vulnerable to fracture even after minor trauma — the spine behaves like a long bone. Plain X-rays may miss fractures (especially in a fully ankylosed rigid spine). CT (and MRI if neurological deficit present) is mandatory. Neurological deficit + fracture requires urgent surgical stabilisation.

A normal X-ray does NOT exclude fracture in an ankylosed AS spine. CT is mandatory. Applying traction or starting physiotherapy without imaging is dangerous.

Correct. Anaemia of chronic disease in RA is characterised by normocytic normochromic picture, elevated ferritin (or normal), low serum iron, and low TIBC — reflecting iron sequestration by hepcidin in the context of systemic inflammation.

Anaemia of chronic disease (ACD) is the most common anaemia in active RA. It is normocytic normochromic (sometimes microcytic), with elevated ferritin (acute phase reactant), low serum iron, low TIBC, and reduced transferrin saturation. It results from hepcidin-mediated iron sequestration and reduced erythropoietin response, both driven by chronic inflammation (IL-6, TNF-alpha).

The normocytic normochromic picture with elevated ferritin (not reduced, as in iron deficiency) points to anaemia of chronic disease. IDA shows microcytic hypochromic cells with low ferritin; haemolysis shows elevated LDH/bilirubin; megaloblastic shows macrocytosis.

Correct. Bilateral ground-glass opacities in a patient on methotrexate mandates immediate methotrexate cessation — MTX pneumonitis carries up to 5-10% mortality if drug is continued. Corticosteroids are added after stopping MTX.

Methotrexate-induced pneumonitis is a serious adverse effect presenting with dry cough, dyspnoea, and bilateral pulmonary infiltrates on CT. It requires immediate cessation of methotrexate and corticosteroid therapy. RA-associated interstitial lung disease is an alternative diagnosis but methotrexate must be stopped first as it can be fatal if continued.

Methotrexate pneumonitis is an emergency requiring immediate drug cessation, not dose escalation or continuation. NSAIDs have no role in managing MTX-induced lung toxicity.