Overview

Multisystem inflammatory syndrome in children (MIS-C) is a serious condition that appears to be linked to coronavirus disease 2019 (COVID-19). Most children who become infected with the COVID-19 virus have only a mild illness. But in children who go on to develop MIS-C, some organs and tissues — such as the heart, lungs, blood vessels, kidneys, digestive system, brain, skin or eyes — become severely inflamed. Signs and symptoms depend on which areas of the body are affected.

MIS-C is considered a syndrome — a group of signs and symptoms, not a disease — because much is unknown about it, including its cause and risk factors. Identifying and studying more children who have MIS-C may help to eventually find a cause. The U.S. Centers for Disease Control and Prevention and the National Institutes of Health are working with doctors and researchers across the country to learn more about risk factors for MIS-C, share data, and improve diagnosis and treatment of MIS-C.

MIS-C is rare, and most children who have it eventually get better with medical care. But some kids rapidly get worse, to the point where their lives are at risk.

Much remains to be learned about this emerging inflammatory syndrome. If your child shows any signs or symptoms, get help fast.

Symptoms

Signs and symptoms of multisystem inflammatory syndrome in children (MIS-C) include those below, though not all children have the same symptoms.

  • Fever that lasts 24 hours or longer
  • Vomiting
  • Diarrhea
  • Pain in the stomach
  • Skin rash
  • Feeling unusually tired
  • Fast heartbeat
  • Rapid breathing
  • Red eyes
  • Redness or swelling of the lips and tongue
  • Redness or swelling of the hands or feet
  • Headache, dizziness or lightheadedness
  • Enlarged lymph nodes

Emergency warning signs of MIS-C

  • Severe stomach pain
  • Difficulty breathing
  • Bluish lips or face
  • New confusion
  • Inability to wake up or stay awake

When to see a doctor

If your child has any of the emergency warning signs listed above — or is severely sick with other signs and symptoms — get care immediately. Take your child to the nearest emergency department or call 911 or your local emergency number.

If your child isn't severely ill but shows other signs or symptoms of MIS-C, contact your child's doctor right away for advice. Doctors may want to do tests — such as blood tests, or imaging tests of the chest, heart or abdomen — to check for areas of inflammation and other signs of MIS-C.

Causes

The exact cause of MIS-C is not known yet, but it appears to be an excessive immune response related to COVID-19. Many children with MIS-C have a positive antibody test result. This means they've had a recent infection with the COVID-19 virus. Some may have a current infection with the virus.

Risk factors

In the U.S., more Black and Latino children have been diagnosed with MIS-C compared with children of other races and ethnic groups. Studies are needed to help determine why MIS-C affects these children more often than others. Factors may include, for example, differences in access to health information and services as well as the possibility of risks related to genetics.

Most children with MIS-C are between the ages of 3 and 12 years old, with an average age of 8 years old. Some cases have also occurred in older children and in babies.

Complications

Many specialists consider MIS-C to be a complication of COVID-19. Without early diagnosis and appropriate management and treatment, MIS-C can lead to severe problems with vital organs, such as the heart, lungs or kidneys. In rare cases, MIS-C could result in permanent damage or even death.

Prevention

The best way to help prevent your child from getting MIS-C is to take action to avoid exposure to the COVID-19 virus and teach your child how to do the same. Follow the guidelines of the U.S. Centers for Disease Control and Prevention:

  • Keep hands clean. Wash hands often with soap and water for at least 20 seconds. If soap and water aren't available, use a hand sanitizer that contains at least 60% alcohol.
  • Avoid people who are sick. In particular, avoid people who are coughing, sneezing or showing other signs that indicate they might be sick and contagious.
  • Practice social distancing. This means that you and your child should stay at least 6 feet (2 meters) from other people when outside of your home.
  • Wear cloth face masks in public settings. When it's difficult to practice social distancing, both you and your child — if he or she is at least 2 years old — should wear face masks that cover the nose and mouth.
  • Avoid touching your nose, eyes and mouth. Encourage your child to follow your lead and avoid touching his or her face.
  • Cover your mouth with a tissue or your elbow when you sneeze or cough. You and your child should practice covering your mouths when you sneeze or cough to avoid spreading germs.
  • Clean and disinfect high-touch surfaces every day. This includes areas of your home such as doorknobs, light switches, remotes, handles, countertops, tables, chairs, desks, keyboards, faucets, sinks and toilets.
  • Wash clothing and other items as needed. Follow manufacturers' instructions, using the warmest appropriate water setting on your washing machine. Remember to include washable plush toys.
Oct. 08, 2020
  1. For parents: Multisystem inflammatory syndrome in children (MIS-C) associated with COVID-19. Centers for Disease Control and Prevention. https://www.cdc.gov/coronavirus/2019-ncov/daily-life-coping/children/mis-c.html. Accessed Sept. 8, 2020.
  2. Multisystem inflammatory syndrome in children (MIS-C) associated with coronavirus disease 2019 (COVID-19). Centers for Disease Control and Prevention. https://emergency.cdc.gov/han/2020/han00432.asp. Accessed Sept. 8, 2020.
  3. Multisystem inflammatory syndrome in children and adolescents temporally related to COVID-19. World Health Organization. https://www.who.int/news-room/commentaries/detail/multisystem-inflammatory-syndrome-in-children-and-adolescents-with-covid-19. Accessed Sept. 8, 2020.
  4. AskMayoExpert. Multisystem inflammatory syndrome in children (MIS-C). Mayo Clinic; 2020.
  5. Information for healthcare providers about multisystem inflammatory syndrome in children (MIS-C). Centers for Disease Control and Prevention. https://www.cdc.gov/mis-c/hcp. Accessed Sept. 15, 2020.
  6. What CDC is doing about multisystem inflammatory syndrome in children (MIS-C). Centers for Disease Control and Prevention. https://www.cdc.gov/mis-c/cdc-response/index.html. Accessed Sept. 9, 2020.
  7. Help stop the spread of COVID-19 in children. Centers for Disease Control and Prevention. https://www.cdc.gov/coronavirus/2019-ncov/daily-life-coping/children/protect-children.html. Accessed Sept. 15, 2020.
  8. Coronavirus disease 2019 (COVID-19): How to protect yourself & others. Centers for Disease Control and Prevention. https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/prevention.html. Accessed Sept. 14, 2020.
  9. Godfred-Cato S, et al. COVID-19-associated multisystem inflammatory syndrome in children — United States, March-July 2020. MMWR Morbidity and Mortality Weekly Report. 2020; doi:10.15585/mmwr.mm6932e2.
  10. Son MBF, et al. Coronavirus disease 2019 (COVID-19): Multisystem inflammatory syndrome in children. https://www.uptodate.com/contents/search. Accessed Sept. 15, 2020.
  11. Levy ER (expert opinion). Mayo Clinic. Sept. 27, 2020.
  12. Multisystem inflammatory syndrome in children (MIS-C) interim guidance. American Academy of Pediatrics. https://services.aap.org/en/pages/2019-novel-coronavirus-covid-19-infections/clinical-guidance/multisystem-inflammatory-syndrome-in-children-mis-c-interim-guidance. Accessed Sept. 8, 2020.
  13. NIH-funded project seeks to identify children at risk for MIS-C. National Institutes of Health. https://www.nih.gov/news-events/news-releases/nih-funded-project-seeks-identify-children-risk-mis-c. Accessed Sept. 9, 2020.
  14. Health department-reported cases of multisystem inflammatory syndrome in children (MIS-C) in the United States. Centers for Disease Control and Prevention. https://www.cdc.gov/mis-c/cases/index.html. Accessed Sept. 11, 2020.
  15. Aronoff SC, et al. The natural history of SARS-Cov-2 related multisystem inflammatory syndrome in children (MIS-C): A systematic review. Journal of the Pediatric Infectious Diseases Society. 2020; doi:10.1093/jpids/piaa112.
  16. Ahmed M, et al. Multisystem inflammatory syndrome in children: A systematic review. EClinicalMedicine. 2020; doi:10.1016/j.eclinm.2020.100527.
  17. Feldstein LR, et al. Multisystem inflammatory syndrome in U.S. children and adolescents. The New England Journal of Medicine. 2020; doi:10.1056/NEJMoa2021680.
  18. Dufort EM, et al. Multisystem inflammatory syndrome in children in New York state. The New England Journal of Medicine. 2020; doi:10.1056/NEJMoa2021756.

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Multisystem inflammatory syndrome in children (MIS-C) and COVID-19