D-dimer is a strong predictor of mortality in paediatric hematological-oncological patients with severe infections.

Objectives: The purpose of this study was to explore the prognostic value of inflammatory biomarkers, including CRP, PCT, IL-6, IL-10,and the thrombotic biomarker D-dimer in predicting the development of severe infections and mortality in children with hematological malignancies.

Methods: A retrospective observational study was performed from October 2018 to December 2020 at the Children's Hospital, Zhejiang University School of Medicine.It collected clinical data of pediatric patients diagnosed with hematological malignancies who experienced febrile illnesses. Blood samples were obtained within 24 h of fever onset to test for D-dimer, Fibrinogen, PT, APTT, CRP, PCT and serum cytokine levels.

Results: Analysis revealed that with escalating infection severity, biomarkers such as CRP, PCT, IL-6, IL-10 and D-dimer progressively increased. The D-dimer level showed the highest accuracy (AUC of 0.930) in predicting mortality among children with severe infections. The combined analysis of IL-6 and D-dimer significantly improves the accuracy of prognosis in sepsis cases. A 60-day survival rate was lower for patients with D-dimer levels above 1.91 mg/L.

Conclusion: In conclusion, D-dimer levels have proven to be a reliable biomarker for predicting mortality in children with hematological malignancies experiencing severe infections.