To investigate the intermediate-term health impacts of pediatric inflammatory multisystem syndrome temporally-associated with SARS-CoV-2 (PIMS-TS).

Using a standardized questionnaire in a multicenter study, follow-up data from acute PIMS-TS patients were collected, including detailed information on patient characteristics, clinical progression, laboratory findings, imaging results, and outcomes. These follow-up data were then linked to data from the patients' acute-phase PIMS disease, as recorded in the German (and Innsbruck, Austria) PIMS-TS registry.

Of the 920 cases originally documented in the acute-phase PIMS-TS registry, follow-up data were collected from 6 pediatric centers on 127 patients; 81 patients were male. Mean age during the acute phase was 8 years (SD: 4.4 years). Median follow-up time was 125 days (IQR: 50.5 to 290.5 days). Overall, a majority of patients achieved full recovery, with 81/127 doing so even before their first follow-up visit. However, abnormal echocardiographic findings continued in 18/67 patients. Coronary dilatation persisted in 14/33 (42%) and resolved in all but 3. Residual cardiovascular and general symptoms were more frequent in older children, as well as among those who had required intensive care unit treatment during the acute phase.

Our findings confirm the generally favorable intermediate-term outcome in patients with PIMS-TS. However, a subset of patients in our cohort, particularly older children and those requiring intensive care unit care during the acute phase, experienced prolonged symptoms, especially cardiovascular complications. Close follow-up and multidisciplinary care are recommended in order to monitor these patients' recovery.