Doctors urge prompt recognition of COVID-19-linked MIS-C

Last Updated: 2020-09-09

By Megan Brooks

NEW YORK (Reuters Health) - Multisystem inflammatory syndrome in children (MIS-C) associated with COVID-19 is characterized by "extreme" inflammation, fever, abdominal symptoms, conjunctivitis and rash, according to a systematic review of 662 MIS-C cases from around the world.

"Children will typically show signs/symptoms of MIS-C three to four weeks after COVID-19 infection and many will progress rapidly into shock and cardiorespiratory failure," the authors report in EClinicalMedicine.

Children do not need to exhibit the classic upper respiratory symptoms of COVID-19 to develop MIS-C, "which is frightening," Dr. Alvaro Moreira of The University of Texas Health Science Center at San Antonio said in a news release. "Children might have no symptoms, no one knew they had the disease, and a few weeks later, they may develop this exaggerated inflammation in the body."

"Prompt recognition of MIS-C is of utmost importance as it can improve outcomes," Dr. Moreira told Reuters Health by email. "Most individuals will respond accordingly with a multidisciplinary team focusing on cardiac resuscitation, respiratory support, and administration of intravenous immunoglobulin and corticosteroids."

In their report, Dr. Moreira and colleagues summarize the typical clinical presentation and outcomes of 662 children with MIS-C. Their mean age was 9.3 years; 52% were boys.

All of the children had fever, 74% had abdominal pain/diarrhea, 68% had vomiting, 52% conjunctivitis and 56% rash.

Per the definition of MIS-C, neutrophilia and lymphocytopenia were common. The mean percentage of neutrophils was elevated (80.7%) and the mean percentage of lymphocytes was low (9.8%).

Extreme elevations in procalcitonin (203-fold upper limit of normal), interleukin-6 (103-fold ULN) and troponin (49-fold ULN) were common.

The children remained in the hospital for more than a week on average (7.9 days), with nearly three-quarters (71%) requiring admission to the intensive-care unit (ICU). Eleven children died in the hospital.

More than one in five (22%) of the children required mechanical ventilation; about 4% required extracorporeal membrane oxygenation (ECMO). Sixty-percent required vasopressor support and/or fluid resuscitation.

Echocardiogram was performed in 581 children (88%) and results were abnormal in 314 children (54%). Depressed left ventricular ejection fraction was the most common abnormality (45%).

Aneurysms occurred in 47 children (8%). "These are children who are going to require significant observation and follow-up with multiple ultrasounds to see if this is going to resolve or if this is something they will have for the rest of their lives," Dr. Moreira said in the release.

Intravenous immunoglobulin (IVIG) therapy was the most common medication (76%), followed by vasoactive agents (52%), and corticosteroids (52%).

Nearly half of children with MIS-C had an underlying medical condition, and of those, half of the individuals were obese or overweight. "Generally, in both adults and children, we are seeing that patients who are obese will have a worse outcome," Dr. Moreira said in the news release.

He noted that more research is needed to understand why some children may be more susceptible to developing MIS-C than others. Currently, "we do not know which children will develop MIS-C and the long-term implications of this hyperinflammatory syndrome," Dr. Moreira told Reuters Health.

SOURCE: https://bit.ly/2RcyAI5 EClinicalMedicine, online September 4, 2020.