Prognostic Biomarkers Predict Dengue Shock and Organ Failure

By LabMedica International staff writers
Posted on 07 Sep 2016
There are presently no biomarkers that can predict the incidence of dengue shock and/or organ failure, although the early identification of risk factors is important in determining appropriate management to reduce mortality.

Mortality rates among patients who have been hospitalized with severe dengue are 1.6% to 10.9%, and death in adults is mainly due to the development of dengue shock and organ dysfunction. The prognostic value of serum procalcitonin (PCT) and peripheral venous lactate (PVL) levels as biomarkers of dengue shock and/or organ failure have been evaluated.

Image: The Cobas e 411 immunoassay analyzer (Photo courtesy of Roche Diagnostics).

Scientists at Mahidol University (Bangkok, Thailand) conducted a prospective observational study among adults hospitalized for confirmed viral dengue infection between October 2013 and July 2015. Of 160 patients with dengue, 128 (80.0%) patients had dengue without shock or organ failure, whereas 32 (20.0%) patients developed dengue with shock and/or organ failure. Laboratory tests were conducted at admission, including a complete blood count and blood chemistry assessment, and samples for the measurement of PCT and PVL were collected.

PCT was measured using an electrochemiluminescence method (Elecsys BRAHMS PCT, Roche Diagnostic, Mannheim, Germany) using a Roche Diagnostic Cobas e 411 immunoassay analyzer. The detection limit for the PCT assay was 0.02 ng/mL. PVL levels were measured by a colorimetric assay with an enzymatic reaction using a Cobas C Systems autoanalyzer (Roche/Hitachi, Indianapolis, IN, USA). All sera collected at admission and two weeks after admission were tested using four separate capture enzyme-linked immunosorbent assays (ELISA) for immunoglobulin M (IgM) and IgG against dengue virus and Japanese encephalitis virus.

The team found that patients with dengue shock and/or organ failure had significantly higher PCT levels and higher PVL levels, higher hemoglobin concentrations, increased hematocrit values above baseline, elevated while blood counts (WBC), higher absolute bands, increased atypical lymphocyte counts, higher alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. However, patients with dengue shock and/or organ failure had significantly lower platelet counts and albumin levels. Dengue shock patients with non-clearance of PCT and PVL expired during hospitalization.

The authors concluded that a PCT equal to or greater than 0.7 ng/mL and a PVL equal to or greater than 2.5 mmol/L were independently associated with dengue shock and/or organ failure. The combination of PCT and PVL levels could be used as prognostic biomarkers for the prediction of dengue shock and/or organ failure. The study was published on August 26, 2016, in the journal Public Library of Science Neglected Tropical Diseases.

Related Links:
Mahidol University
Roche Diagnostic
Roche/Hitachi

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