Methylprednisolone pulses as an initial treatment in hyperinflammatory syndrome after COVID-19 in children: evaluation of laboratory data, serial echocardiography and outcome: a case series
Authors: Sadeghi Payman , Gorji Mojtaba , Assari Raheleh , Tahghighi Fatemeh , Raeeskarami Seyed Reza , Ziaee Vahid 
Published: December 2022

Abstract
Background
Hyper-inflammatory syndrome in children and young adult occur 2–6 weeks after COVID-19 infection or closed contact with COVID-19 persons. In this study, the laboratory data and echocardiography and abdominal ultrasonography assessments were evaluated before and after Methylprednisolone pulse as an initial treatment of hyper-inflammatory syndrome. Therefore, the aim of this study is to assessment the clinical manifestations and laboratory data and outcome after methylprednisolone pulse as an initial treatment.

Method
In this retrospective study, the demographic status, clinical features, laboratory data, echocardiography, abdominal ultrasound, treatment and outcome of 31 pediatric patients under 16 years old, with inflammatory process after COVID-19 were evaluated. The clinical assessments, laboratory data, sonography and echocardiography were evaluated before and after methylprednisolone pulse. The patients were divided in two age group < and ≥ 7 years old and the clinical manifestations were compared with each other. The Mann–Whitney U test was used to assess the difference in quantitative variables between two groups. To compare pre- and post- treatment values, Wilcoxol test was used. To assess the correlation between qualitative variables chi-square test was used. The level of significant was considered 0.05. These patients with fever and hyper-inflammation features admitted to the referral pediatric rheumatology ward in Children Medical Center of Tehran University of medical sciences, from April 2020 to May 2021 were assessed.

Result
The mean age ± SD were (5.94 ± 3) and 51.6% (16) patients were male and 48.4% (15) patients were female. The most documented of previous COVID infection were antibody positive in about 27 (87%) patients. Moreover, 1 (3.8%) was PCR positive, 2 (7.7%) were positive in both PCR and serology and 3(11.5%) had closed contact with COVID-19 patients. About 9(29%) of patients were admitted in Intensive Care Unit (ICU). There were significant correlation between days of delay in starting treatment and ICU admission (P-value = 0.02). The mortality rate was negative in patients and no re-hospitalization was documented. There were significant differences (P-value < 0.05) between lymphocytes, platelet, Erythrocyte Sedimentation rate, C-reactive protein, Aspartate transaminase, Alanine transaminase and ferritin before and after treatment. Skin rashes and cardiac involvement totally as carditis (myocarditis, vulvulitis and pericarditis) (33.3%) and coronary involvements (53.3%) were the most prominent initial presentation in patients. There were near significant correlation (P-value = 0.066) between ferritin level and carditis before treatment. Cervical lymphadenopathy was seen significantly more in ≥ 7 years old (P-value = 0.01).

Conclusion
Multisystem inflammatory system in children as a hyperinflammatory syndrome could be treated with first step methylprednisolone pulse with decreasing inflammation in laboratory data and cardiac involvements and good outcome. Furthermore, the ferritin level may be one of the predictor of severe hyper-inflammatory syndrome leading to aggressive and urgent treatment with methylprednisolone pulse.