A retrospective comparative analysis of factors affecting the decision and outcome of initial intravenous immunoglobulin alone or intravenous immunoglobulin plus methylprednisolone use in children with the multisystem inflammatory syndrome

Background For children with the multisystem inflammatory syndrome(MIS-C), intravenous immunoglobulins (IVIG) with or without methylprednisolone are the most effective treatment. In this study, IVIG combined with methylprednisolone was compared to IVIG used alone in children with MIS-C. Methods This retrospective cohort study was carried out between April 1, 2020, and November 1, 2021. This study covered all children with MIS-C. According to whether they received IVIG alone or IVIG with methylprednisolone as an initial treatment for MIS-C, the patients were split into two groups. The IVIG dosage for the patients in group I was 2 gr/kg, whereas the IVIG dosage for the patients in group II was 2 gr/kg + 2 mg/kg/day of methylprednisolone. These two groups were contrasted in terms of the frequency of fever, length of hospital stay, and admission to the pediatric intensive care unit. Results The study comprised 91 patients who were diagnosed with MIS-C and were under the age of 18. 42 (46.2%) of these patients were in the IVIG alone group (group I), and 49 (53.8%) were in the IVIG + methylprednisolone group (group II). Patients in group II had a severe MIS-C ratio of 36.7%, which was substantially greater than the rate of severe MIS-C patients in group I (9.5%) (p 0.01). When compared to group I (9.5%), the rate of hypotension was considerably higher in group II (30.6%) ( p = 0.014). Additionally, patients in group II had considerably higher mean serum levels of C-reactive protein. The incidence of fever recurrence was 26.5% in group II and 33.3% in group I, however the difference was not statistically significant ( p > 0.05). Conclusions The choice of treatment for patients with MIS-C should be based on an individual evaluation. In MIS-C children with hypotension and/or with an indication for a pediatric intensive care unit, a combination of IVIG and methylprednisolone may be administered. For the treatment modalities of children with MIS-C, however, randomized double-blind studies are necessary.