D-dimer as an indicator of dengue severity.

Background: Dengue infection is a problem of global concern. The clinical spectrum of the disease varies from an acute febrile course accompanied by mild hemorrhagic manifestations with uneventful recovery to refractory shock and massive bleeding with high mortality. Several mechanisms may be involved in the pathogenesis of bleeding, namely: vasculopathy, thrombocytopenia, coagulopathy and dissiminated intravascular coagulopathy (DIC). Objective: To determine the relationship between D-dimer (DD) levels and clinical outcome in dengue patients. Method: Children with suspected dengue infection admitted to King Chulalongkorn Memorial Hospital were enrolled. D-dimer (DD) was sequentially measured during the course of illness using whole blood and a rapid semiquantitative system (SimpliRed). Diagnosis of dengue infection was confirmed by serology and WHO criteria were used for classifying dengue severity. Results: 41 dengue patients, 22 girls and 19 boys were recruited in the study. The mean age was 9.68 years. There were 12 (29.3 %) cases of dengue fever (DF) and 29 (70.7 %) cases of dengue hemorrhagic fever (DHF). DD was more significantly present in the DHF group (87 %) than in the DF group (13%) (P<0.03). The sensitivity and specificity of DD in predicting severe dengue infection (DHF) were 90% and 67 %, respectively. Sequential analysis of DD showed higher levels at all stages of dengue infection. It correlated with the disease severity. Conclusion: Semiquantitative DD assay measurements in children suffering from dengue infection significantly correlated with dengue severity.