Case Study: Ruling in Multisystem Inflammatory Syndrome - COVID 19 (MIS-C)

Multisystem Inflammatory Syndrome in Children (MIS-C) is a new diagnosis that has come up recently in the pediatric population. It has been classified as a Kawasaki disease-like multisystem inflammatory disease occurring post-COVID-19 infection. The criteria for the diagnosis of MIS-C is a positive serology for COVID-19 along with fulfilling full or partial criteria for diagnosis of Kawasaki disease. MIS-C is treated with high-dose steroids, aspirin, heparin, and repeat EKGs and echocardiograms. The broad diagnosis criterion ensures no cases are missed but at the same time, it is not very sensitive. MIS-C can be deadly in the pediatric population but are there differentials that need to be ruled out to make this criterion more sensitive for MIS-C? In this case report, we present a 12-year-old girl who was diagnosed and treated for MIS-C. MIS-C will be contrasted with Rickettsia typhi, a common flea-borne disease diagnosed in the south Texas population. Rickettsia serology is used to confirm the diagnosis of typhus but most infections are treated without confirmatory tests in the scenario of high clinical suspicion as the test has a high false-negative rate, especially early in the course of the disease. The clinical presentation of typhus overlaps with that of Kawasaki disease. In this case, we present the argument for more specific markers to differentiate MIS-C from typhus, which may cause harm due to the unnecessary treatment of children with steroids and anticoagulation therapy.