Red Flags Related to MIS-C in the Outpatient Setting

AUTHOR:
Jordan N. Watson, MD
Nemours/Alfred I. duPont Hospital for Children

CITATION:
Watson JN. Red flags related to MIS-C in the outpatient setting. Consultant360. Published online March 1, 2021.
 

Carlin RF, Fischer AM, Pitkowsky Z, et al. Discriminating multisystem inflammatory syndrome in children requiring treatment from common febrile conditions in outpatient settings. J Pediatr. 2021;229:26-32.e2. https://doi.org/10.1016/j.jpeds.2020.10.013

This study aims to guide outpatient pediatric health care providers on distinguishing characteristics of the novel multisystem inflammatory syndrome in children (MIS-C) from other common febrile illnesses. The authors of this study discussed some new challenges encountered by health care providers during the pandemic, including providing more care via telemedicine and reluctance of families to seek in-person care. Challenges such as these leave providers making medical decisions with fewer data, making it important to distinguish features of potentially severe and life-threatening disorders, including MIS-C, from common childhood illnesses that can be managed in the outpatient setting.

This case-controlled retrospective study examined data from 44 patients treated for MIS-C at a tertiary care hospital in New York City in April 2020 through June 2020. All of the patients had evidence of cardiac involvement. Features of their clinical presentation were compared with those from a cohort of 181 pediatric patients aged older than 12 months who were evaluated for febrile illnesses during this same time period. The majority of the febrile control group was seen in the outpatient setting at hospital-affiliated primary care sites, and 23 patients were seen in the emergency department. There were no significant differences in the groups regarding sex, race, or ethnicity. There was a significant difference in age, with the average age of the MIS-C cohort at 8.2 years vs 3.5 years in febrile control group.

The authors evaluated both clinical features and laboratory features among the groups. They found the fever curve to be distinguishing, with patients with MIS-C having a greater maximum reported temperature (40.0 °C vs 38.9 °C) and greater total duration of fever reported at time of evaluation (5 days vs 2 days). The authors also evaluated the odds ratios for symptomatology associated with MIS-C. They found that abdominal pain, vomiting, mucosal irritation, neck pain or stiffness, and rash had a higher correlation with patients requiring treatment for MIS-C. They also noted that none of the patients who required treatment for MIS-C had resolution of their fever prior to treatment, suggesting that self-resolution of fever has a lower correlation with MIS-C.

The majority of the patients in the outpatient setting did not have any laboratory testing, so only the laboratory test results from the emergency department control group were compared with the MIS-C group. This was a small cohort, but the authors did find that patients with MIS-C had significantly lower absolute lymphocyte counts, greater percentages in neutrophils, lower initial platelet counts, higher C-reactive protein levels, and higher N-terminal brain natriuretic peptide (ntBNP) levels than febrile controls.

This study gives us helpful red flags to monitor for when evaluating a febrile patient in the outpatient setting. There are some limitations of the study, including that most of the patients evaluated in the outpatient setting were seen via telemedicine vs the patients presenting with MIS-C were initially seen in the emergency department. We should also consider that viral infections contribute to a large portion of pediatric febrile illnesses and that some viral pathogens are seasonal, peaking at various times throughout the year. The data from this study was collected in the spring over a 3-month time period, so it would be interesting to compare data throughout the year to determine whether the same distinguishing characteristics of MIS-C (specifically, fever curve and duration) are seen during different seasons when other viral pathogens are circulating.

Jordan N. Watson, MD, FAAP, is clinical assistant professor of pediatrics at the Sidney Kimmel Medical College at Thomas Jefferson University in Philadelphia, Pennsylvania. She is a general pediatrician and a dermatology access physician in the Division of General Pediatrics and the Division of Dermatology at Nemours/Alfred I. duPont Hospital for Children in Wilmington, Delaware