Background

Thyroid and adrenal incidentalomas are common findings on chest-CT imaging. However, most studies on its prevalence were performed in selected populations with specific indications requiring CT-analysis, resulting in inclusion bias. Therefore, we studied a more general population of patients admitted to hospital because of (suspected) COVID-19.

Methods

We included all patients admitted to Zuyderland Medical Centre with (suspected) COVID-19 between March 1, 2020 and March 1, 2021 who underwent chest-CT-imaging. We retrospectively evaluated the presence and diagnostic work-up of incidentalomas. Regression analyses were performed to identify risk factors.

Results

1992 consecutive patients were included. Thyroid and adrenal incidentalomas were found in 95 (4.8%) and 133 (6.7%) patients, respectively. In multivariate analysis female sex (OR:2.64;95%CI:1.71-4.08;p<0.001), age (OR:1.04;95%CI:1.02-1.06;p<0.001), hypertension (OR:1.67;95%CI:1.09-2.58;p=0.019) and previous malignancy (OR:2.20;95%CI:1.09-4.54;p=0.028) were associated with thyroid incidentalomas. Adrenal incidentalomas were associated with female sex (OR:1.46;95%CI:1.02-2.08;p=0.04), age (OR:1.02;95%CI:1.00-1.03;p=0.043), previous malignancy (OR:2.97;95%CI:1.73-5.09;p<0.001), and COPD (OR:2.14;95%CI:1.44-3.19;p<0.001). Out of 228 patients with incidentalomas, only 22 (9.6%) underwent further diagnostic work-up. In 77 (33.8%) patients the incidentaloma was already known. 129 (56.6%) patients did not receive any work-up. Reasons for no additional assessment were: death during hospitalization (31.8%) and severe comorbidities (7.7%). In 78 (60.5%) patients there was no apparent reason for refraining from work-up.

Conclusion

Thyroid and adrenal incidentalomas are common findings on chest CT scans with a prevalence of 4.8% and 6.7% respectively, in an unselected population of COVID-19 patients. We noticed that diagnostic work-up for incidentalomas was limited during the COVID pandemic.