Differences in the clinical picture at the onset of diagnosis of severe autoimmune hypothyroidism in children depending on the time of diagnosis: before or during the SARS-CoV-2 pandemic.

Introduction: There are few data about effects of COVID-19 on thyroid disease presentation in children, due to difficulties in healthcare services access.

Aim of the study: To assess the differences in hypothyroidism presentation before and during the COVID-19 pandemic.

Material and methods: All paediatric patients with autoimmune hypothyroidism (AIT) diagnosed from January 2017 to December 2022 were analysed.

Results: A total of 150 subjects were enrolled (94 in before and 56 during the pandemic period). Severe AIT was detected in 7.4% before and 12.5% during the pandemic. Age at the onset in the pre-pandemic period was lower ( p = 0.04). Diagnosis delay (time elapsed from onset of symptoms and diagnosis) was significantly different between the before and during the pandemic groups ( p = 0.02). In the pre-pandemic period the TSH value was 447.7 ±59.1, and it was 713.7 ±104.4 mUI/l during the pandemic ( p = 0.04), whereas mean fT4 values were 2.66 ±0.34 and 0.58 ±0.08 ng/l, respectively ( p = 0.0002). Significantly greater thyroid volume and bone age delay SDS were observed during the pandemic ( p = 0.04). Neurological symptoms were mostly observed during the pandemic, especially slow speech and impaired school performance.

Conclusions: A higher rate of severe AIT was observed during the pandemic period, mostly related to difficulties in access to healthcare services. The diagnosis delay led to a more severe biochemical thyroid hormone profile, goitre, and more frequent presence of bone age delay and neurological symptoms at the onset. Recognizing hypothyroidism and recalling symptoms in child-hood, even if often non-specific, is fundamental for avoiding diagnosis delay.