Article in Japanese

A case of multisystem inflammatory syndrome in children associated with COVID-19

Masami ASAI^1）,Mihoko MIZUNO^1）,Ryuji YASUI^1）,Yusuke KOBAYAKAWA^1）,Yuko TSUNODA^1）,Kozue HAYAKAWA^1）

Most cases of coronavirus disease 2019 (COVID-19) are mild in children, but multisystem inflammatory syndrome in children (MIS-C) secondary to COVID-19 is occasionally reported. Here, we report the case of an 8-year-old boy who was asymptomatic after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, but subsequently developed MIS-C. He experienced fever and vomiting, and a PCR test for SARSCoV- 2 at a local doctor’s office was positive. His fever, vomiting, and diarrhea continued and he was referred to our hospital on the fourth day of illness. Blood tests revealed high ketone bodies and he was hospitalized for supposed dehydration. Based on his clinical symptoms, test results, and a history of close contact with his grandmother, who had developed COVID-19 about three weeks before his hospitalization, he received a diagnosis of MIS-C. Treatment with intravenous immunoglobulin (IVIG), methylprednisolone (mPSL), and aspirin (acetylsalicylic acid [ASA]) was started. His fever quickly resolved, but recurred and IVIG was administered again. This time the resolution of his fever was maintained and the dose of mPSL was thus decreased, but his fever recurred after the reduction in mPSL dose. The dose of mPSL was consequently increased and the fever again resolved. Afterward, the mPSL dose was gradually tapered but his fever did not recur and he was discharged on day 19 of hospitalization. The steroid was discontinued about one week after discharge, while ASA was continued for two months. When multiple organ disorder is seen 2‒6 weeks after SARS-CoV-2 infection in children, MIS-C should be suspected.

---

1）Daido Children’s Medical Center, Daido Hospital

Key words	COVID-19, multisystem inflammatory syndrome, MIS-C, Kawasaki Disease, intravenous immunoglobulin
Received	January 21, 2022
Accepted	July 15, 2022

34 (3)：205─211,2022