The most common hemorrhagic manifestations
are mild and include a positive tourniquet test, skin
hemorrhages (petechiae, hematomas), epistaxis
(nose bleed), gingival bleeding (gum bleed), and
microscopic hematuria. More serious types of
hemorrhage include vaginal bleeding, hematemesis,
melena, and intracranial bleeding.
Evidence of plasma leakage due to increased vascular
permeability consists of at least one of the following:
• An elevated hematocrit ≥20% above the
population mean hematocrit for age and sex. • A decline in hematocrit after volume-replacement
treatment of ≥20% of the baseline hematocrit. • Presence of pleural effusion or ascites detected
by radiography or other imaging method. • Hypoproteinemia or hypoalbuminemia as
determined by laboratory test.
WHO is currently reevaluating the clinical case
definition for dengue fever and DHF. Studies from
different countries have reported life-threatening
complications from dengue in the absence of one or
more of the current criteria for DHF. Despite the
name, the critical feature that distinguishes DHF
from dengue fever is not hemorrhaging, but rather
plasma leakage resulting from increased vascular
permeability.
Dengue shock syndrome (DSS) is defined as any
case that meets the four criteria for DHF and
has evidence of circulatory failure manifested b