Rapid resolution of severe pericardial effusion using anakinra in a patient with COVID-19 vaccine-related acute pericarditis relapse: a case report.

Background: Pericarditis, along with myocarditis, is being increasingly reported after the coronavirus disease 2019 (COVID-19) vaccine, but the best treatment strategy in this specific setting is still unclear. Case summary: We report a case of acute pericarditis after the second dose of mRNA COVID-19 vaccine with recurrence of large pericardial effusion after a previous pericardiocentesis and anti-inflammatory drugs tapering. The patient was successfully treated with the recombinant interleukin-1 receptor antagonist anakinra, with full reabsorption of the pericardial effusion and an abrupt drop of the inflammatory markers within 72 h. The patient was discharged a few days later, with a further decrease of the inflammatory markers and no residual symptoms. Discussion: Anakinra is being increasingly used in the treatment of recurrent pericarditis due to its capability to interrupt the autoinflammatory response leading to deleterious cytokine storms. On account of its high efficacy and rapid onset, it has been reported to rapidly reverse large inflammatory pericardial effusions. Pericarditis and myocarditis have been reported after the COVID-19 vaccine, but this is the first case of COVID-19 vaccine-related pericarditis and pericardial effusion successfully treated with anakinra, avoiding a second pericardiocentesis.