Objective: The objective of our study was to determine the rate of pulmonary embolism (PE) on pulmonary CT angiography (CTA) in children and adolescents visiting adult-centered community hospitals. We also investigated alternative diagnoses that may account for presenting symptoms., Materials and Methods: We identified consecutive children and adolescents (age ≤ 19 years) who underwent pulmonary CTA during a 12- and 24-month period, respectively, at two community hospitals. Staff radiologists' clinical interpretations of pulmonary CTA studies were compared with interpretations performed by a blinded, subspecialty-trained thoracic radiologist, with a third tie-breaking interpretation performed in cases of discrepancy. A systematic review of pulmonary CTA studies for possible alternative diagnoses was completed. Diagnostic rates of PE on pulmonary CTA studies in adults at these hospitals were also reviewed for comparison., Results: The study population consisted of 130 individuals (32 boys and 98 girls; median age, 18 years; age range, 11-19 years) who underwent 137 examinations, 11 as inpatients and 126 as outpatients. CTA studies were positive for PE in six patients (4.6%). CTA showed an important alternative diagnosis, such as pulmonary consolidation, in 27 patients (21%). By comparison, pulmonary CTA studies in adults at these two hospitals yielded a 16% positive rate for PE., Conclusion: The prevalence of PE in young ambulatory patients with clinically suspected PE at adult-centered community hospitals is substantially lower than in adults. Alternative diagnoses, such as pulmonary consolidation and pneumothorax, are discovered more frequently than PE on pulmonary CTA studies. Pulmonary CTA should be used with discretion in adolescents, especially when radiography may provide the necessary diagnosis.