A Young Adult with Covid-19 Associated Multisystem Inflammatory Syndrome

Background: Coronavirus Disease 2019 (COVID-19) is an evolving entity with a myriad of clinical presentations and complications. Most cases of COVID-19 associated multisystem inflammatory syndrome (MIS) have been reported in children with little data in adults. Here we present a case of MIS in a 19-year-old African American adult. Case Presentation: The patient is a previously healthy 19-year-old African American female who presented with 5 days of nausea, vomiting, diarrhea, fever, chills, headache, and malaise. She was diagnosed with COVID- 19 24 days before presentation and remained asymptomatic since testing positive. On presentation, the patient's vitals were significant for a fever of 102.2 F, blood pressure of 97/56, and heart rate of 123. Laboratory workup showed elevated creatinine, and inflammatory markers including procalcitonin, lactate dehydrogenase, ferritin, Creactive protein, and, D-dimer. A multidisciplinary approach comprising of critical care, cardiology, rheumatology, and infectious disease was undertaken. The initial hospital course was complicated by hypotension requiring pressor support, and an episode of supraventricular tachycardia which resolved with adenosine. Additionally, the patient had a brief episode of paroxysmal atrial fibrillation, which self resolved. Initial transthoracic echocardiogram (TTE) showed an ejection fraction (EF) of 30% with left wall hypokinesis. The patient was successfully treated with 1 dose of intravenous immunoglobulin (IVIG), and Solu-Medrol 1 g daily for three days. The patient was monitored with serial troponins, B-natriuretic peptide, and inflammatory markers. Acute kidney injury present on admission resolved within two days. A follow-up TTE obtained three days later showed a significant improvement in EF to 45%. The patient's symptoms resolved within three days of treatment. Discussion: MIS should be considered in adults presenting with atypical gastrointestinal, cardiac, and musculoskeletal symptoms with elevated inflammatory markers in the setting of a recent diagnosis of COVID-19. Cardiac manifestations such as arrhythmias and wall motion abnormalities should be expected. Unlike MIS in children who display features of Kawasaki disease, adults often lack these overlapping features. Inflammatory markers including procalcitonin, lactate dehydrogenase, C-reactive protein, and ferritin can be used to monitor treatment response as they trend down with appropriate management. Intravenous steroids and IVIG can be effective in managing this clinical entity by improving cardiac parameters such as EF, although long term prognosis remains to be analyzed. Despite limited data, it is reasonable to postulate that MIS may be caused by Covid-19 associated cytokine storm and severe inflammatory response that entails multisystem dysfunction even in individuals without underlying medical conditions.