Polymyalgia rheumatica and GCA suspicion — KFP-style written assessment

KFP 1 (10 marks)

A 71-year-old woman presents with 5 weeks of bilateral shoulder pain, morning stiffness lasting about 75 minutes, and new hip girdle ache. CRP 48 mg/L, ESR 72 mm/h. RF and anti-CCP negative. No headache, no visual symptoms, no jaw or limb claudication. Examination: restricted active shoulder movement bilaterally, no peripheral synovitis, temples normal. ^[1]

1. Score her against the 2012 ACR/EULAR classification criteria and state the performance of the threshold she meets. (3) ^[1]
2. What single bedside investigation would most strengthen the diagnosis, and what finding are you looking for? (2) ^[3]
3. She is offered a rapid-access rheumatology appointment in 5 days. Should you start prednisolone today? Justify against the referral recommendations. (3) ^[9]
4. What GCA screening questions must you document before she leaves? (2) ^[2]

Model answers

1. Morning stiffness >45 minutes (2 points), hip pain (1 point), RF/anti-CCP negative (2 points), no peripheral joint pain (1 point) = 6 points, above the threshold of 4. A score of 4 or more carries 68% sensitivity and 78% specificity against all mimics (88% specificity versus shoulder conditions, 65% versus RA). ^[1]
2. Shoulder ultrasound: bilateral subacromial-subdeltoid bursitis supports PMR (unilateral sens 80%/spec 68%; bilateral sens 66%/spec 89%; bursal thickness over 3 mm separates PMR from rotator cuff tendinopathy — mean 6.9 mm vs 2.3 mm). Adding ultrasound to the criteria raises specificity to 81%. ^[3]
3. No. The international referral recommendations state that where suspected PMR is referred via rapid access, glucocorticoid commencement should be deferred until specialist evaluation — early steroids can blur the diagnostic picture. The exception that would override: any cranial or large-vessel feature, which mandates immediate treatment. ^[9]
4. New or changed headache; scalp or temporal artery tenderness; jaw claudication when chewing; any visual disturbance including transient monocular loss; limb claudication on walking or using arms; fever. Any positive answer converts the plan to immediate 40-60 mg prednisolone and 24-hour specialist review. ^[2]