Crystal Arthropathies and Degenerative Joint Disorders — WACS Viva & Clinical Scenarios (Rheumatology and Clinical Immunology)

Exam-style crystal arthropathies and degenerative joint disorders viva scenarios with examiner probes and model answers for Internal Medicine candidates.

Scenarios covered

• SCENARIO 1: A 54-year-old male with hypertension, type 2 diabetes mellitus, and chronic kidney disease stage 3b presents to the emergency department with a 12-hour history of severe, excruciating pain, redness, and swelling of the right first metatarsophalangeal joint. He reports no preceding trauma. Outline your immediate diagnostic approach to safely exclude septic arthritis, interpret synovial fluid findings, and construct an acute pharmacotherapeutic management plan considering his underlying renal impairment.
• SCENARIO 2: A 48-year-old female presents for outpatient evaluation four weeks after the resolution of her second episode of podagra within the past twelve months. Her baseline serum urate is 520 micromol/L and estimated glomerular filtration rate is 82 mL/min/1.73 m². Formulate a comprehensive long-term strategy for urate-lowering therapy initiation, including indications, drug selection, target serum urate thresholds, flare prophylaxis duration, and patient counseling on treatment adherence.
• SCENARIO 3: A 72-year-old female presents with acute onset of severe pain, effusion, and warmth in her left knee. Plain radiography reveals linear, punctate radiodensities within the fibrocartilage of the menisci and hyaline articular cartilage. Detail the diagnostic evaluation using compensated polarised light microscopy, outline acute symptom control, and construct a structured laboratory panel to screen for associated secondary endocrine and metabolic conditions.
• SCENARIO 4: A 58-year-old male with chronic tophaceous gout and recurrent polyarticular arthritis has been taking allopurinol 100 mg daily irregularly. Physical examination reveals extensive subcutaneous nodular deposits over the olecranon bursa and proximal interphalangeal joints. A recent ultrasound of the knee demonstrates the double contour sign. Explain the principles of dose titration, target serum urate concentrations in severe tophaceous disease, screening for HLA-B*58:01 allele in high-risk populations, and the role of alternative or add-on pharmacological agents.
• SCENARIO 5: A 63-year-old female farmer presents with worsening mechanical bilateral knee pain and early morning stiffness lasting less than 20 minutes, exacerbated by weight-bearing and relieved by rest. Detail the clinical diagnostic criteria, Kellgren-Lawrence radiographic grading, step-wise multimodal conservative and pharmacological management, and clear indications for referral for total knee arthroplasty.