BACKGROUND: Quantitative computed tomography (QCT) has been widely applied for opportunistic screening for osteoporosis in adults, but it is rarely used in pediatric patients. OBJECTIVE: This study aimed to investigate the feasibility of QCT and the prevalence of bone mineral density (BMD) deficits at the spine in pediatric patients undergoing an abdominal computed tomography (CT) for other indications. MATERIALS AND METHODS: Pediatric patients who underwent a clinical abdominal CT scan from October 2018 to November 2020 were recruited for this retrospective cross-sectional study. Lumbar trabecular BMD was evaluated by QCT. The relationships of treatment variables and other potential risk factors with low BMD were analyzed via the signed-rank test and logistic regression analysis. RESULTS: A total of 748 pediatric patients were included. The QCT scans revealed low lumbar BMD (Z-score ≤ -2) in 86 (11.5%) patients. A history of chemotherapy or radiation therapy (β = 3.925, P <
0.001), a history of chronic corticosteroid exposure (β = 4.852, P <
0.001), older age (10.0-17.9 years vs. 1.0-9.9 years
β = 2.306, P = 0.001), and short stature (height ≤ the 3rd percentile vs. height >
the 3rd percentile
β = 1.920, P = 0.047) were significantly associated with low BMD in pediatric patients. CONCLUSION: QCT could be applied for opportunistic screening for low BMD in pediatric patients. Patients with cancer or renal disease, or those with a history of chemotherapy, radiation therapy, or chronic corticosteroid exposure, have a greater incidence of low BMD and constitute high-risk populations for BMD loss.