SG kids prone to multisystem inflammatory syndrome amid high COVID-19 transmission

Children in Singapore are at risk of developing multisystem inflammatory syndrome (MIS-C), especially due to the increased community transmission of COVID-19 in 2021, according to a study. MIS-C incidence may also intensify with the arrival of new variants of concern (VOCs) and relaxation of pandemic restrictions.

“Physicians should suspect MIS-C in febrile children with features of Kawasaki disease and in children with recent COVID-19 infection together with gastrointestinal symptoms, shock, and haematologic abnormalities of coagulopathy, lymphopaenia, and thrombocytopaenia to diagnose MIS-C early and initiate prompt treatment with intravenous immunoglobulin (IVIg) and steroids,” the researchers said.

The research team, led by Dr Karen Donceras Nadua, performed this observational study on patients who met the Singapore Ministry of Health (MOH) criteria for MIS-C from January 2020 to December 2021 in KK Women’s and Children’s Hospital. They reviewed medical records to gather data on clinical presentation, disease course, treatment received, and outcomes.

Twelve patients (median age 7.5 years, eight male) were identified, all of whom presented with mucocutaneous symptoms similar to Kawasaki disease. Other systems normally involved were haematological (coagulopathy 100 percent, lymphopaenia 91.7 percent, and thrombocytopaenia 75.0 percent), gastrointestinal (75.0 percent), and cardiovascular (83.3 percent). [Ann Acad Med Singap 2022;51:669-676]

“Involvement of other systems such as neurological or respiratory system is less frequently reported in MIS-C,” the researchers said. [J Pediatr 2020;226:45-54.e1; Pediatr Res 2022;91:1334-1349; Pediatr Infect Dis J 2020;39:e340-346; Pediatr Pulmonol 2021;56:837-848]

“Our case series also confirms the high morbidity of MIS-C with a high proportion requiring intensive care unit (ICU) care, although mortality is low (≤2 percent). [Lancet Child Adolesc Health 2021;5:473-482; Lancet Child Adolesc Health 2021;5:323-331; JAMA Pediatr 2021;175:1281-1283]

Early treatment

Of the patients, six (50.0 percent) had shock and were admitted to the ICU. Most of them received treatment with IVIg and steroids within 2 days of hospitalization. All the children survived, while majority showed normal echocardiograms and no long-term organ sequelae at 6 months postdischarge.

“Multidisciplinary management, timely diagnosis, and early initiation of treatment with IVIg and steroids likely contributed to comparatively good outcomes,” the researchers said. “Our cases highlight the need for continued awareness of MIS-C among physicians and surveillance of its incidence, short-, and long-term outcomes.”

Nadua and her team further said that the impact of the Omicron surge on MIS-C incidence and short- and long-term outcomes calls for continued surveillance and future studies.

The study was limited by its retrospective, single-centre design, and small sample size. Timings for evaluation of inflammatory markers and echocardiograms were also not standardized. In addition, the researchers did not actively survey for other system outcomes, such as neurological and respiratory.

“MIS-C is a rare inflammatory syndrome with multisystem involvement affecting children exposed to COVID-19,” the researchers said. “This condition is rarely reported in East Asia and was not detected in Singapore until 2021.”