Transcript Management of Dengue Fever

Management of Dengue Fever
Dr David Tran
16/09/09
Classic clinical dengue fever

Incubation period 3 to 14 days

Sudden onset of fever with severe headache

Retro-orbital pain, fatigue

Often associated with myalgia and arthralgia

Duration of fever usually 5 to 7 days

Sometime maculopapular rash

(usually 4 to 7 days)
(50% to 66% of cases)
Other non specific signs as inflamed pharynx,
gastro-intestinal symptoms
Classic definition of dengue fever
(WHO 1997)
Hemorrhagic manifestations /
biologic abnormalities

Petechiae, purpura

Gum bleeding, epistaxis, menorrhagia, gastro-
intestinal bleedings (rare)

Thrombocytopenia, leukopenia with lymphopenia

Mild elevation of hepatic transaminases & LDH
Definition of dengue
hemorrhagic fever (WHO 1997)
Dengue hemorrhagic fever &
Dengue shock syndrome





Physiopathology: capillary leakage &
hemorrhagic manifestations.
4 to 7 days after the onset (at approximately the
date of defervescence)
Abdominal pain, vomiting, consciousness
troubles, hypothermia
Marked decrease in platelet count.
Mortality: up to 10 or 20%
Definition of dengue
shock syndrome (WHO 1997)
Diagnosis of dengue hemorrhagic fever
(triad of symptoms)

Hemorrhagic manifestations

Platelet count < 100.000

Evidence of plasma leakage (Hematocrite 
(often >3rd day of illness)
pleural effusion, ascites, hypoproteinemia)
Lowest platelet count by day of illness
in adult dengue hemorrhagic patients
160
140
120
100
80
60
40
20
0
1st day
2nd day
3rd day
4th day
5th day
6th day
7th day
8th day
Dengue shock syndrome

Rapid weak pulse & low blood pressure
(BP < 90mmHg)

The duration of this shock is short after
appropriate volume replacement therapy
(Colloid or Cristalloid infusions)

Mortality rate is up to 40%
Different clinical presentation of
dengue fever
Serodiagnosis of dengue fever




Serology (IgM capture ELISA)
Problem: negativity of the test early in
the course of the disease > should be
performed only 4 to 5 days after the
onset of fever.
IgM: remain positive for 3 to 6 month
IgG: remain positive for life
Dengue NS1 antigen testing

Early detection of Ag NS1 in blood sample of
infected patients > confirm early acute infection

Detection of all 4 types of dengue serotypes

Result available in 15 min. (BioRad® chromatographic
strip test)

High specificity (100%) and positive predictive value
Although in some reports, the same efficiency of
detection for virus of the 4 serotypes has been described
for the Dengue Early ELISA and Strip tests (Dussart et
al., 2008),
A recent analysis of the performance of these tests in
Vietnam suggests a lower sensitivity for DENV-2
compared with DENV-1 and DENV-3.
Problem of sensibility of NS1 detection tests
(Ramirez, diagnostic microbiology & infectious disease, Sept 2009)
These tests in Vietnam suggests a lower sensitivity for DENV-2 compared with DENV-1
and DENV-3. Also, a decreased sensitivity for DENV-4 with the Dengue Early ELISA has
been reported in studies from South America (Bessoff et al., 2008; Dussart et al., 2008).
A lower sensitivity for DENV-2 has been described in samples from Vietnam (Hang et al.,
2009) tested by the PLATELIA™ systems (ELISA and Strip) and belonging to the Asian
genotype 1 (according to the classification of Twiddy et al., 2002).
Sensitivity of NS1 Ag detection tests
according to the day of illness
(Mc Bride, Diagnostic Microbiology & Infectious Diseases, 64 – 2009 – 31,36)
Management of dengue virus
infected patient

Most of cases can be managed on an outpatient basis
(antipyretic like paracetamol, bed rest, oral hydratation)

Platelet counts and hematocrite determination should
be repeated at least every 24 hours

Patient with platelet count < 100.000 should be
hospitalized
syndrome)
(high risk for dengue hemorrhagic & dengue shock