Limping as Presenting Symptom of Multisystem Inflammatory Syndrome in Children (MIS-C): a Case Report of Large Vessel Vasculitis in MIS-C.

Background: Multisystem Inflammatory Syndrome of children (MIS) is a pathological condition that occurs in response to a SARS-CoV-2 infection, the syndrome has been described as a "Kawasaki disease"-like illness and the spectrum of associated abnormalities, including vascular complications, remain to be fully defined.

Objective: The aim of this article was to present a case of MISC presented with limping and associated with large vessel vasculitis.

Case presentation: In this article we present a case of 10-year-old male presented to emergency department complaining of limping of one-week duration and left hip pain, associated with high grade prolonged fever, abdominal pain and weight loss. The patient was ill looking, couldn't bear weight and was admitted to pediatric intensive care unit. Laboratory workup have rule out infectious and malignant causes as well as known rheumatological causes. Inflammatory markers were elevated. Ultrasound, Doppler ultrasound, CT scan of the affected hip showed evidence of vasculitis extending from the left femoral artery reaching the left common iliac artery with intramural thrombus. According to WHO criteria the patient diagnoses was MIS-C. treatment was started immediately with IVIG and steroids in addition to anticoagulants, dramatic improvement was noticed within 24 hours. Patient was discharged after 10 days of hospitalization.

Conclusion: MIS-C is a new emerging medical diagnosis after the pandemic of COVID-19. it is described a Kawasaki-like syndrome that affect small to medium vessels. This case reports a large vessel vasculitis associated with MIS-C, it helps the understand the extend of this new syndrome and the variety of complaints that may result from large vessels involvement.