Complications Of A Severe Case Of Multisystem Inflammatory Syndrome In Children

ABSTRACT

Case Presentation A 10 year old male with prior COVID-19 exposure presented with 7 days of fever, rash, cough, vomiting, and hypotension. Laboratory evaluation was notable for SARS-CoV2 antibodies, elevated cardiac enzymes, BNP, and inflammatory markers. Initial echocardiogram showed normal cardiac function and a small LAD coronary aneurysm. He was diagnosed with Multisystemic Inflammatory Syndrome in Children (MIS-C) and given methylprednisolone and IVIG. Within 24 hours, he developed severe LV dysfunction and progressive cardiorespiratory failure requiring VA-ECMO cannulation and anticoagulation with bivalirudin. Cardiac biopsy demonstrated lymphocytic infiltration consistent with myocarditis. On VA-ECMO, he had transient periods of complete AV block. With immunomodulator treatment (anakinra, infliximab) and 5 days of plasmapheresis, inflammatory symptoms and cardiac function improved. He weaned off ECMO, and anticoagulation was transitioned to enoxaparin. He had left sided weakness 5 days later, and brain MRI revealed an MCA infarct. Ten days later, he had focal right sided weakness and repeat MRI showed multiple hemorrhagic cortical lesions, thought to be thromboembolic with hemorrhagic conversion secondary to an exaggerated inflammatory response to an MSSA bacteremia in the setting of MIS-C. Enoxaparin was discontinued. After continued recovery and a slow anakinra and steroid wean, he has normal coronary arteries, cardiac function, and baseline ECG but requires ongoing neurorehabilitation. Discussion(s) COVID-19 infection in children is often mild, but MIS-C is an evolving entity that can present with a wide range of features and severity. This case highlights two concepts. While first degree AV block is often reported in MIS-C, there is potential for progression to advanced AV block. Close telemetry monitoring is critical, especially if there is evidence of myocarditis. MIS-C shares features with Kawasaki disease, with a notable difference being a higher likelihood of shock and cardiac dysfunction in MIS-C. In MIS-C patients with cardiovascular collapse requiring ECMO, there is a risk for stroke. There should be a low threshold for neuroimaging and multidisciplinary effort to guide anticoagulation in these complex cases.