100586 - Acral Recurrent Swelling in Chronic Urticaria: When Should We Suspect Autoinflammatory Disease? A 10-Year Diagnostic Challenge

Background:

Recurrent dactylitis in adults is uncommon and may reflect autoinflammatory, autoimmune, or urticarial disorders. Distinguishing between chronic urticaria with deep swelling and systemic autoinflammatory disease may be challenging when systemic features are absent.

Case Presentation:A 46-year-old male presented with a 10-year history of recurrent painful swelling of digital pulps of fingers and toes, warm and occasionally mildly erythematous, self-limited within 2–3 days and responsive to dexketoprofen. Frequency is currently 1–2 episodes/month (maximum remission: 5 months). No clear triggers were identified.

He subsequently developed transient, non-pruritic erythematous macular lesions (<1 cm) on soles, trunk, and lower limbs, blanching on pressure and resolving within 4–5 days. No fever, serositis, arthritis, uveitis, thrombosis, Raynaud phenomenon, or constitutional symptoms were reported.

Inflammatory markers were repeatedly normal or minimally elevated (CRP ≤7 mg/L). ANA, RF, cryoglobulins, viral serologies, and complement were normal. Transient lupus anticoagulant and borderline anti-β2-glycoprotein I positivity were detected once, with later normalization. Total IgE was elevated (peak 1000 IU/mL). Autoinflammatory NGS panel (MEFV, NLRP3, NLRP12, MVK, TNFRSF1A) was negative.

Skin biopsies (2021, 2023) showed minimal inflammatory changes consistent with urticaria; urticarial vasculitis was considered but not confirmed after multidisciplinary review. Cardiac and abdominal imaging were normal.

Conclusions:Chronic recurrent urticaria with deep acral swelling may clinically mimic angioedema or autoinflammatory disease. Autoinflammatory syndromes should be considered when flares are accompanied by red flags such as recurrent unexplained fever, serositis (abdominal or pleuritic pain), inflammatory arthritis, aphthous ulcers, persistent elevation of acute phase reactants, lymphadenopathy, ocular inflammation, or marked fatigue.

In their absence, with stable long-term course, normal inflammatory markers, and negative genetic testing, a systemic monogenic autoinflammatory syndrome is unlikely. Careful phenotyping and longitudinal follow-up remain essential to detect potential evolution toward a defined systemic inflammatory disorder