Anakinra-Dependent Recurrent Pericarditis: The Role of the R202Q Variant of the MEFV Gene

<b>Background</b>: the role of the R202Q (c.605G>A, p.Arg202Gln) missense variant of the MEFV gene has been debated as either a benign polymorphism or a potentially pathogenic mutation. We report and discuss here the case of a young female with corticosteroid-dependent recurrent pericarditis carrying the homozygous R202Q variant, exhibiting distinctive clinical features possibly influenced by this genetic variant. <b>Methods</b>: a 30-year-old woman with a previous diagnosis of cancer and recent respiratory infection presented with severe pleuritic chest pain, hypotension, tachycardia, and fever. Initial diagnostic evaluation indicated cardiac tamponade, and emergent pericardiocentesis was performed. Despite initial treatment with NSAIDs, colchicine, and corticosteroids, the patient experienced multiple recurrences. Genetic testing identified homozygous R202Q variant in the MEFV gene. Given the corticosteroid dependency and recurrent nature of her condition, IL-1 inhibitor anakinra was introduced, leading to significant improvement, although tapering below 150 mg per week failed to prevent recurrences. <b>Results</b>: the introduction of anakinra resulted in rapid symptom relief and resolution of pericardial effusion. However, attempts to taper or discontinue anakinra led to pericarditis recurrences. Ultimately, a maintenance dose of 50 mg every three days was established, which maintained remission for 18 months without recurrence. Despite multiple tapering attempts, further reduction in anakinra dosage was unsuccessful without triggering relapses. <b>Conclusions</b>: the R202Q variant, although typically considered benign, may contribute to an autoinflammatory phenotype resembling familial Mediterranean fever. This case underscores the potential pathogenicity of the homozygous R202Q variant in recurrent pericarditis and its responsiveness to IL-1 inhibition. In patients with corticosteroid-dependent recurrent pericarditis, genetic testing for the R202Q variant should be considered when anti-IL-1 drugs cannot be withdrawn. Further studies are warranted to elucidate the variant's role in pericardial inflammation and guide personalized treatment strategies.