This nationwide cohort study found a marked inpatient health care and economic burden for VTE among children and adolescents, with mortality risk significantly increased among infants younger than 1 year.
Pediatric inpatient VTE occurred at a hospital-based incidence of 15.3 per 10,000 pediatric cases per year in Germany from 2020 to 2024.
Infants younger than 1 year represented a disproportionately large share of pediatric VTE cases, comprising nearly one quarter of the cohort.
Risk factors for VTE in children varied systematically by age group, with infection, chronic organ failure, and congenital diseases more common in younger patients.
Pulmonary embolism (PE) occurred in 11.1% of VTE cases and showed a marked female predominance among patients whose main diagnosis was PE.
In-hospital mortality in the pediatric VTE cohort was 3.7%, with mortality risk significantly increased among infants aged 4 years or younger.
The study identified a marked inpatient health care and economic burden associated with pediatric VTE.
This research used nationwide hospital data from Germany (2020–2024) to examine blood clots—specifically deep vein thrombosis and pulmonary embolism (clots in the lungs)—in children and teenagers under age 20. The study found that about 15 out of every 10,000 hospitalized children were diagnosed with a blood clot, and nearly a quarter of these cases were babies under one year old. The reasons children develop clots changed with age: infections, organ problems, and birth defects were more common triggers in very young children, while cancer was most common in school-aged children (5–14 years), and an inherited tendency to clot (thrombophilia) was a risk at all ages. One in nine children with a blood clot also had a clot in their lungs (pulmonary embolism), and strikingly, about 70% of those hospitalized specifically for a lung clot were female. The overall death rate during hospitalization was 3.7%, but babies and toddlers under age 4 were more than three times as likely to die in the hospital compared to older children. These findings highlight that very young children face the greatest danger from blood clots. This research suggests that blood clots in children, while relatively uncommon, carry a serious risk of death—especially in infants—and place a significant burden on hospitals and health care resources. The authors emphasize that there is currently a lack of high-quality evidence to guide doctors on the safest and most effective treatments for children with blood clots, underscoring the need for dedicated research in this population rather than relying solely on adult treatment guidelines.
Friebe S, Scheinert D, Tokur Sonuvar E, Kirsten T, Freisinger E. (2026). Inpatient Characteristics and Outcomes of Venous Thromboembolism Among Children and Adolescents.. JAMA network open. https://doi.org/10.1001/jamanetworkopen.2026.17459