On this page
Study tools
Write your answer
Saved on this device. No marking — you are the marker.
Stem
A 38-year-old woman presents with a one-year history of episodic colour change in her fingers on cold exposure — they turn white, then blue, then red on rewarming. Over the last three months the attacks have become more frequent and severe, they are now affecting the index and middle fingers of the right hand more than the left, and she has developed a painful, shallow ulcer at the tip of the right index finger. On examination she has sclerodactyly, several periungual telangiectasiae, and two small digital pulp pitting scars. Nailfold capillaroscopy shows dilated, tortuous capillary loops with areas of dropout. ANA is positive at 1:1280.
Questions
a) Is this primary or secondary Raynaud phenomenon? List the four features in the stem that support your answer. (2 marks)
Model answer: This is SECONDARY Raynaud phenomenon (1 mark). Four supporting features (any four): (1) older age of onset (38, over 30); (2) asymmetric attacks (right index/middle fingers more than left); (3) digital ulcer and pitting scars (tissue ischaemia — never occurs in primary Raynaud); (4) ABNORMAL nailfold capillaroscopy (dilated tortuous loops with dropout); (5) positive ANA at high titre; (6) sclerodactyly and periungual telangiectasiae pointing to systemic sclerosis (1 mark for four). Primary Raynaud is benign, symmetric, in young women with normal nailfold capillaries, negative ANA and no tissue loss.
b) Systemic sclerosis is the most likely underlying disease. Which three autoantibodies would you request, and what does each associate with? (3 marks)
Model answer: Any three with correct association (1 mark each):
- Anti-centromere antibody — LIMITED cutaneous systemic sclerosis / CREST syndrome (Calcinosis, Raynaud, Esophageal dysmotility, Sclerodactyly, Telangiectasia) and pulmonary arterial hypertension.
- Anti-Scl-70 (anti-topoisomerase I) — DIFFUSE cutaneous systemic sclerosis and interstitial lung disease.
- Anti-RNA polymerase III — diffuse cutaneous disease and a high risk of scleroderma renal crisis. (Other acceptable: anti-U1-RNP — mixed connective tissue disease; anti-Th/To or anti-PM/Scl.)
c) Outline the general and pharmacological management of her Raynaud phenomenon, naming the first-line drug class and one agent added for severe disease. (3 marks)
Model answer: General — cold avoidance, hand and whole-body warming (gloves, heated clothing), smoking cessation, reduce caffeine and stress, and avoid beta-blockers and decongestants (unopposed α vasoconstriction worsens attacks) (1 mark). Pharmacological — calcium-channel blockers are first-line (nifedipine modified-release, or amlodipine); add a PDE-5 inhibitor (sildenafil or tadalafil) for refractory disease; topical nitrates (glyceryl trinitrate) are an alternative/adjunct (1 mark). Severe disease / recurrent ulcers — IV prostacyclin (iloprost) infusion in hospital for critical ischaemia, and the endothelin-receptor antagonist bosentan specifically reduces the number of NEW digital ulcers (1 mark). Treatment of the underlying systemic sclerosis and organ screening (PFTs, echocardiogram, HRCT chest) must proceed in parallel.
d) Two months later she develops sudden severe pain and black discolouration of the right middle fingertip with absent capillary refill. What is this complication, and what is the immediate management? (2 marks)
Model answer: This is CRITICAL DIGITAL ISCHAEMIA with tissue necrosis (gangrene) — a rheumatological emergency in systemic-sclerosis-associated Raynaud (1 mark). Immediate management: admit, warm the limb, give intravenous prostacyclin (iloprost) infusion (the specific acute therapy), provide analgesia, treat the underlying disease, care for the ulcer/wound with antibiotics if infected, and consider surgical digital sympathectomy for refractory cases or amputation if necrosis is irreversible (1 mark). Oral CCB or PDE-5 inhibitors alone are insufficient in an acute ischaemic crisis.