Impact of apoptotic biomarkers for prognosis of dengue disease severity among eastern Indian patients.

Dengue virus (DENV) induced severe manifestations is a precursor for fatality among infected patients. Previous autopsy examinations of severe dengue (SD) patients reported presence of apoptotic cells in liver, brain, intestinal and lung tissues. Thus, serum-level of major apoptotic proteins of dengue patients was evaluated in the current study, along with their biochemical parameters. Patients were categorized according to World Health Organization (WHO)-defined classification. DENV-infection was screened among 165 symptomatic patients by quantitative reverse transcription polymerase chain reaction, antidengue IgM, and IgG ELISA. Serum levels of apoptotic (Capase-3,7,8, Bcl-2 and FasL) and hepatic-markers, lipid profile, hematological parameters of 78 dengue-positive patients were determined by sandwich-ELISA/immunoturbidimetry/auto-analyzer. Significantly higher levels of caspase-3,7,8 and FasL was detected among SD patients compared to those without warning (WOW) signs. Amongst biochemical parameters, bilirubin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase serum concentrations significantly increased among severe patients. Principal component analysis followed by hierarchical clustering differentiated severe and with warning dengue patient groups from those WOW using caspase-3,7,8 and FasL biomarkers-thus clearly distinguishing severe-dengue group. Correlation analyses also established strong positive correlation between caspase-3,7,8 and FasL. Thus, serum level of caspase-3,7,8 and FasL during early stage of infection could be used as biomarkers for WHO-defined dengue disease severity.