Pediatric Pulmonary Infarction and Infarction-Like Pulmonary Injury: An Etiology-Oriented Narrative Review

Abstract: Pulmonary infarction (PI) has traditionally been regarded as a complication of pulmonary embolism (PE). However, increasing evidence suggests that pediatric PI represents a heterogeneous spectrum of ischemic lung injury extending beyond classic thromboembolic disease. This narrative review adopted an etiology-oriented framework to summarize the epidemiology, pathophysiology, imaging features, diagnostic strategies, treatment approaches, prognosis, and follow-up considerations of pediatric PI and infarction-like pulmonary injury. Published pediatric PI-related cases were also descriptively summarized. Pediatric PI remains underrecognized and lacks standardized diagnostic criteria. Compared with adults, children demonstrate greater etiologic heterogeneity, including thromboembolic PE, in situ pulmonary artery thrombosis, congenital pulmonary developmental anomalies, such as extralobar pulmonary sequestration, immune-mediated vascular injury, and infection-related microthrombosis. Imaging findings including Hampton hump, reverse halo sign, and cavitary transformation may suggest PI but have not been systematically validated in children. Imaging evaluation must also balance diagnostic performance with radiation exposure under the "as low as reasonably achievable" principle. Treatment strategies differ substantially according to underlying mechanisms: thromboembolic PI generally requires anticoagulation, congenital vascular anomalies are primarily managed surgically, whereas inflammatory and infection-related phenotypes often require immunomodulatory or multidisciplinary management. Evidence regarding long-term pulmonary outcomes and chronic thromboembolic pulmonary hypertension in children remains limited. Pediatric PI and infarction-like pulmonary injury should be considered a heterogeneous ischemic lung injury syndrome rather than a single disease entity. Etiology-oriented classification is critical for diagnosis, individualized treatment, and long-term management. Further multicenter studies are needed to establish standardized pediatric diagnostic and follow-up frameworks.