Acute Vascular Complications Following Pediatric Allogeneic HSCT

Overview

This retrospective study of 122 pediatric allo-HSCT recipients identified the incidence, timing, and clinical features of acute vascular complications including capillary leak syndrome (CLS), thrombotic microangiopathy (TMA), and veno-occlusive disease (VOD) within 100 days post transplant. The findings highlight the variability and severity of endothelial dysfunction-related complications and underscore the challenges in early detection and management.

Background

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative treatment for various hematologic malignancies and immune or metabolic disorders. Despite improvements in overall survival and reduced treatment-related mortality, complications such as graft-versus-host disease (GVHD) and endothelial dysfunction remain significant challenges. Vascular complications like CLS, TMA, and VOD typically occur early post transplant and are associated with high mortality. Their clinical presentations vary widely, complicating timely diagnosis and intervention.

Data Highlights

Key Findings

• Vascular complications such as CLS, TMA, and VOD occur within the first 100 days post allo-HSCT and are linked to endothelial damage.
• CLS manifests as plasma leakage causing hypotension, weight gain, and edema unresponsive to diuretics.
• VOD results from hepatic sinusoidal endothelial injury leading to hepatomegaly, portal hypertension, ascites, and jaundice.
• TMA presents variably but typically includes hemolytic anemia, thrombocytopenia, and acute renal or CNS impairment.
• Prophylactic use of defibrotide and ursodeoxycholic acid was common to reduce VOD risk.
• GVHD prophylaxis primarily involved cyclosporine, with a significant portion of patients requiring corticosteroid therapy for acute GVHD.

Clinical Implications

Early recognition of vascular complications post allo-HSCT is critical due to their variable presentations and high mortality risk. Prophylactic strategies such as defibrotide and ursodeoxycholic acid may reduce VOD incidence. Close monitoring for signs of endothelial dysfunction can facilitate timely interventions to improve outcomes in pediatric allo-HSCT recipients.

Conclusion

Acute vascular complications following pediatric allo-HSCT are common and clinically heterogeneous, reflecting underlying endothelial injury. Improved awareness and early detection strategies are essential to mitigate morbidity and mortality associated with these complications.

References

1. Original Study Authors/Year -- Acute Vascular Complications Following Pediatric Allogeneic Hematopoietic Stem Cell Transplantation