Evolving Perspectives on Pediatric EBMT Criteria for SOS/VOD Diagnosis

Overview

The pediatric EBMT (pEBMT) criteria for diagnosing sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) enable earlier detection and treatment compared to traditional Seattle and Baltimore criteria. Incorporating transfusion refractory thrombocytopenia (TRT) and recognizing anicteric presentations, the pEBMT criteria improve sensitivity and specificity, potentially enhancing patient outcomes.

Background

Sinusoidal obstruction syndrome (SOS), also known as veno-occlusive disease (VOD), is a serious complication following hematopoietic stem cell transplantation (HSCT), traditionally diagnosed using Seattle or Baltimore criteria. These criteria have limitations, especially in pediatric populations, due to rigid requirements such as hyperbilirubinemia and time constraints. The European Society for Blood and Marrow Transplantation (EBMT) recently proposed separate diagnostic criteria for adults and children, emphasizing clinical features like transfusion refractory thrombocytopenia and anicteric presentations to facilitate earlier diagnosis and intervention.

Data Highlights

Key Findings

• The pEBMT criteria identified a higher incidence of SOS/VOD (15.9%) compared to modified Seattle (12.3%) and Baltimore (6.6%) criteria.
• Diagnosis using pEBMT criteria occurred approximately 2.5 to 3 days earlier than with traditional criteria.
• Transfusion refractory thrombocytopenia (TRT) was present in 75% of patients at diagnosis, highlighting its sensitivity as an early marker.
• Approximately 61% of patients were anicteric at diagnosis under pEBMT criteria, though most developed hyperbilirubinemia later.
• Early intervention with defibrotide (DF), facilitated by pEBMT criteria, is associated with improved survival and reduced morbidity.
• Retrospective data support the sensitivity and specificity of pEBMT criteria, but prospective validation is needed.

Clinical Implications

Clinicians should consider adopting the pEBMT criteria for earlier and more sensitive diagnosis of SOS/VOD in pediatric HSCT patients, particularly by monitoring transfusion refractory thrombocytopenia and recognizing anicteric presentations. Early diagnosis enables timely initiation of defibrotide treatment, which is linked to better outcomes. Awareness of baseline hepatomegaly and ascites is essential to avoid diagnostic confounders.

Conclusion

The pEBMT criteria represent a significant advancement in the diagnosis of pediatric SOS/VOD by enabling earlier detection and treatment through incorporation of novel clinical markers. While promising, prospective studies are warranted to confirm these findings and potentially extend criteria updates to adult populations.

References

1. EBMT Adult Criteria 2016 -- Diagnosis and severity criteria for SOS/VOD
2. EBMT Pediatric Criteria 2018 -- Pediatric-specific diagnostic criteria for SOS/VOD
3. McDonald et al. -- Transfusion refractory thrombocytopenia as a marker for SOS/VOD
4. Embaby et al. 2021 -- Refractory thrombocytopenia as an early sensitive marker
5. Szmit et al. 2022 -- Prospective comparison of Seattle and pEBMT criteria
6. Ragoonanan et al. 2023 -- Retrospective comparison of SOS/VOD diagnostic criteria