Post-COVID-19 Multisystem Inflammatory Syndrome in Adults (MIS-A) With Elevated Levels of Soluble Urokinase Plasminogen Activator Receptor (suPAR) Treated With Anakinra: A Case Report

The COVID-19 pandemic has brought attention to a newly identified syndrome of multisystem inflammation. This potentially fatal complication of the disease was initially observed in children and later in adults. It affects primarily unvaccinated patients and may manifest within a timeframe of 2-12 weeks following infection. Soluble urokinase plasminogen activator receptor (suPAR), a novel biomarker, highlights the severity of inflammation and the degree of immune system activation. Herein, we report a case of a patient with multisystem inflammatory syndrome in adults (MIS-A) and markedly elevated suPAR levels, successfully treated with interleukin-1 (IL-1) receptor antagonist. A 59-year-old female was admitted to our hospital due to febrile illness (up to 40°C) with chills, vomiting, non-bloody diarrhea, and abdominal pain for four days prior to her admission. She tested positive for SARS-CoV-2 12 weeks before her presentation. During hospitalization, the patient deteriorated clinically with multiorgan involvement and hemodynamically instability, with concomitant markedly elevated inflammatory markers. Extensive workup with high suPAR levels led to post-COVID-19 MIS-A diagnosis, and treatment with dexamethasone and an interleukin-1 receptor antagonist (IL-1ra), anakinra, was administered. The subcutaneous injection of anakinra effectively and safely deterred MIS-A. Further research is needed to investigate the role of interleukin-1 inhibitors for the management of this potentially life-threatening condition.