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Published on: November 10, 2023
Non-thyroidal illness syndrome and SARS-CoV-2-associated multisystem inflammatory syndrome in children
V Calcaterra1,2, G Biganzoli3, D Dilillo4
1Pediatric and Adolescent Unit, Department of Internal Medicine, University of Pavia, Via Aselli 2, 27100, Pavia, Italy. valeria.calcaterra@unipv.it.
Insights
A low FT3 level is common in children with multisystem inflammatory syndrome (MIS-C). Thyroid function (TF) assessment can help understand MIS-C
Area of Science:
- Pediatric Endocrinology
- Pediatric Critical Care
- Infectious Diseases
Background:
- Multisystem inflammatory syndrome in children (MIS-C) is a severe complication of COVID-19.
- MIS-C can lead to significant alterations in endocrine function, particularly thyroid function (TF).
- Understanding these alterations is crucial for managing affected children.
Purpose of the Study:
- To assess thyroid function (TF) in children diagnosed with MIS-C.
- To evaluate the impact of TF abnormalities on MIS-C disease severity.
- To explore the relationship between TF, metabolic profiles, and disease severity.
Main Methods:
- Retrospective analysis of pediatric patients with MIS-C admitted between November 2019 and January 2021.
- Definition of Non-Thyroidal Illness Syndrome (NTIS) based on thyroid hormone levels (FT3, FT4, TSH) in critically ill patients without prior hormonal issues.
- Utilized Principal Component Analysis (PCA) to analyze associations between TF, metabolic parameters (glucose, lipids), and a composite disease severity score.
Main Results:
- 23 out of 26 MIS-C patients (88.4%) exhibited NTIS.
- Low FT3 levels were observed in 65.3% of patients with NTIS.
- PCA revealed correlations between TF (FT3, FT4), lipid profiles (cholesterol, triglycerides), insulin resistance indices (TyG), and disease severity, suggesting a link between catabolic states and illness severity.
Conclusions:
- Abnormal thyroid function, particularly low FT3, is a frequent finding in children with MIS-C.
- Thyroid function assessment is valuable for evaluating the systemic impact of MIS-C.
- TF monitoring may aid in long-term follow-up, management, and prognosis of MIS-C in children.
Purpose:
COVID-19 disease may result in a severe multisystem inflammatory syndrome in children (MIS-C), which in turn may alter thyroid function (TF). We assessed TF in MIS-C, evaluating its impact on disease severity.
Methods:
We retrospectively considered children admitted with MIS-C to a single pediatric hospital in Milan (November 2019-January 2021). Non-thyroidal illness syndrome (NTIS) was defined as any abnormality in TF tests (FT3, FT4, TSH) in the presence of critical illness and absence of a pre-existing hormonal abnormality. We devised a disease severity score by combining severity scores for each organ involved. Glucose and lipid profiles were also considered. A principal component analysis (PCA) was performed, to characterize the mutual association patterns between TF and disease severity.
Results:
Of 26 (19 M/7F) patients, median age 10.7 (IQR 5.8-13.3) years, 23 (88.4%) presented with NTIS. A low FT3 level was noted in 15/23 (65.3%), while the other subjects had varying combinations of hormone abnormalities (8/23, 34.7%). Mutually correlated variables related to organ damage and inflammation were represented in the first dimension (PC1) of the PCA. FT3, FT4 and total cholesterol were positively correlated and characterized the second axis (PC2). The third axis (PC3) was characterized by the association of triglycerides, TyG index and HDL cholesterol. TF appeared to be related to lipemic and peripheral insulin resistance profiles. A possible association between catabolic components and severity score was also noted.
Conclusions:
A low FT3 level is common among MIS-C. TF may be useful to define the impact of MIS-C on children's health and help delineate long term follow-up management and prognosis.
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