Unique presentations of the post COVID-19 infection, multisystem inflammatory syndrome in children

Introduction: The epidemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV- 2), causing coronavirus disease 2019 (COVID-19), continues to affect most of the world's population. In children, the respiratory and systemic involvement appears to have a much more benign course in comparison to adults, with almost no fatalities reported. However, we are now encountering a post-infectious immune mediated condition, termed, multisystem inflammatory syndrome in children (MIS-C). In most cases the main features are prolonged fever and elevated inflammatory markers. Many of the patients present with abdominal pain and varying degrees of myocardial involvement, from mild reduction in cardiac output to the most alarming manifestation of cardiovascular shock. Results: We present two patients with unusual manifestations of MIS-C related to post COVID-19 infection: an infant born to a mother who was severely ill at the very end of pregnancy, presenting with prolonged fever, rash, pericardial effusion, and evidence of coronary arteries wall dilation thickening as a result of inflammation, and, a teenage girl with severe cardiac tamponade without the more common cardiac manifestations of myocardial involvement. Discussion: Post COVID-19 MIS-C can present with a wide variety of manifestations. The pathophysiologic mechanisms underlying these inflammatory responses in infants are yet to be elucidated. Physicians should be aware of such presentations since rapid diagnosis and treatment are key for a favourable outcome. Statement of novelty: We present two unique manifestations of post COVID-19 infection which, to date, are not discussed frequently in the literature.