Pulmonary Nodule in Children: A Retrospective Study of Radiologic Findings and Systemic Implications

Pulmonary nodules (PNs) in children are often detected incidentally through chest radiographs or computed tomography (CT) scans. However, there is no established diagnostic algorithm to guide the clinical diagnosis and management of paediatric PNs. This study aims to identify PN characteristics that may signal systemic diseases or malignancies in children.

This single-centre, retrospective study reviewed the medical records of patients aged 0-18 years diagnosed with a PN between October 2007 and October 2023. Data collected included demographics, underlying systemic diseases, symptoms, diagnostic tests, imaging reasons, radiological findings, final diagnoses, and follow-up.

A total of 206 children were included in the study, with 54.9% male. PNs were identified due to respiratory symptoms in 43.7% of cases, and incidentally in 56.3%. A total of 59.2% of children had an underlying systemic disease. PNs were detected by CT in 100% of cases and by chest radiography in 6.3%. In 66% of cases, PNs were nonspecific. Notably, 23.3% of patients had a newly diagnosed systemic disease after the detection of a PN. Larger PNs (≥ 5 mm) and specific radiological features (e.g., ground-glass opacity, fibrosis, cavitation) were more commonly associated with newly diagnosed systemic diseases. A PN diameter of ≥ 5 mm predicted malignancy, while ≥ 3.8 mm indicated a higher likelihood of systemic disease.

Pulmonary nodules in children can be early indicators of newly diagnosed systemic diseases and malignancies. Nodule size, distribution, and radiological features may serve as important predictors for identifying underlying systemic diseases or malignancies in paediatric patients.