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Population-based study of multisystem inflammatory syndrome associated with COVID-19 found that 36% of children had
Robin Kahn1,2, Stefan Berg3,4, Lillemor Berntson5
1Department of Paediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden.
Insights
Multisystem inflammatory syndrome in children (MIS-C) following COVID-19 can lead to persistent symptoms and abnormal cardiac findings. Structured follow-up is crucial for children diagnosed with MIS-C, especially older ones or those requiring intensive care.
Area of Science:
- Pediatrics
- Infectious Diseases
- Cardiology
Background:
- Multisystem inflammatory syndrome in children (MIS-C) is a rare but serious condition linked to COVID-19.
- Understanding the long-term outcomes of MIS-C is essential for guiding patient care and management.
Purpose of the Study:
- To describe the clinical outcomes of children diagnosed with MIS-C associated with COVID-19.
- To identify risk factors for persistent symptoms and abnormal findings.
- To suggest appropriate follow-up protocols.
Main Methods:
- A national, population-based, longitudinal, multicentre study using Swedish data from December 2020 to May 2021.
- Inclusion criteria: World Health Organization criteria for MIS-C.
- Outcomes assessed at 2 and 8 weeks post-diagnosis.
Main Results:
- 133 children with MIS-C were analyzed.
- At 2 weeks, 43% had abnormal laboratory or imaging results.
- At 8 weeks, 36% reported persistent symptoms, and 5% had abnormal echocardiograms. Older children and those in intensive care had more symptoms and cardiac abnormalities.
Conclusions:
- A significant proportion of children experience persistent symptoms 8 weeks after MIS-C diagnosis.
- Older age and intensive care admission are risk factors for poorer outcomes.
- Structured follow-up visits are recommended for all children recovering from MIS-C.
Aim:
Our aim was to describe the outcomes of multisystem inflammatory syndrome in children (MIS-C) associated with COVID-19.
Methods:
This national, population-based, longitudinal, multicentre study used Swedish data that were prospectively collected between 1 December 2020 and 31 May 2021. All patients met the World Health Organization criteria for MIS-C. The outcomes 2 and 8 weeks after diagnosis are presented, and follow-up protocols are suggested.
Results:
We identified 152 cases, and 133 (87%) participated. When followed up 2 weeks after MIS-C was diagnosed, 43% of the 119 patients had abnormal results, including complete blood cell counts, platelet counts, albumin levels, electrocardiograms and echocardiograms. After 8 weeks, 36% of 89 had an abnormal patient history, but clinical findings were uncommon. Echocardiogram results were abnormal in 5% of 67, and the most common complaint was fatigue. Older children and those who received intensive care were more likely to report symptoms and have abnormal cardiac results.
Conclusion:
More than a third (36%) of the patients had persistent symptoms 8 weeks after MIS-C, and 5% had abnormal echocardiograms. Older age and higher levels of initial care appeared to be risk factors. Structured follow-up visits are important after MIS-C.
