Multisystem inflammatory syndrome in children: clinical presentation, management, and short- and long-term outcomes.

Objective: In this study, it was aimed to evaluate the demographic, clinical and laboratory characteristics of MIS-C patients in our hospital, to share our treatment approach, and to assess the outcomes of short- and long-term follow-up.

Methods: MIS-C patients who were admitted and treated in our hospital between July 2020 and July 2021 were evaluated. Demographic, clinical, laboratory, and follow-up data were collected from patient records retrospectively.

Results: A total of 123 patients with MIS-C (median age, 9.6 years) were included the study. Nineteen (15.4%) were mild, 56 (45.6%) were moderate, and 48 (39%) were severe MIS-C. High CRP, ferritin, pro-BNP, troponin, IL-6, and D-dimer values were found in proportion to the severity of the disease (p < 0.001, p < 0.001, p < 0.001, p < 0.001, p = 0.005, p < 0.001), respectively. Two (1.6%) patients died. The mean follow-up period was 7.8 months. Valve failure, left ventricular dysfunction/hypertrophy, coronary involvement, and pericardial effusion were the most common cardiac pathologies in the short- and long-term follow-up of the patients. In the long-term follow-up, the most common reasons for admission to the hospital were recurrent abdominal pain (14.2%), cardiac findings (14.2%), pulmonary symptoms (8%), fever (7.1%), neuropsychiatric findings (6.2%) and hypertension (3.5%). Neuropsychiatric abnormalities were observed significantly more common in severe MIS-C patients at follow-up (p = 0.016). In the follow-up, 6.2% of the patients required recurrent hospitalization.

Conclusion: MIS-C is a serious and life-threatening disease, according to short-term outcomes. In addition to the cardiac findings of patients with MIS-C, long-term outcomes such as neuropsychiatric findings, persistent gastrointestinal symptoms, fever and pulmonary symptoms should be monitored. Key Points • In MIS-C patients, attention should be paid not only to cardiac findings, but also to symptoms related to other systems. • Patients should be followed up in terms of neuropsychiatric findings, persistent gastrointestinal symptoms, fever and pulmonary symptoms that may occur during follow-up.