Long-COVID Symptoms After Multisystem Inflammatory Syndrome in Children During Different Pandemic Waves

This study evaluated long-term non-cardiac complications of multisystem inflammatory syndrome in children (MIS-C) caused by different SARS-CoV-2 variants. It included 116 patients from the Children's Hospital of Krakow. The study found that the frequency and variation of long-COVID symptoms did not significantly differ between the Original/Alpha, Delta, and Omicron variant groups, except for higher fatiguability/weakness in the Original/Alpha group during the 4-12-week follow-up. Older age was identified as an independent factor for long-COVID, rather than the specific variant. Despite a high incidence of long-COVID symptoms, long-term follow-up showed above-average quality of life scores, suggesting an overdiagnosis of non-specific symptoms, with quality of life after MIS-C being comparable to the general pediatric population.