journal reading - revised dengue classsification criteria

7/28/2019 Journal Reading - Revised Dengue Classsification Criteria

1/29

Salva Reverentia Reni Rifanti

Adviser : Taufiqur Rahman, MD, Pediatrician

Department of PediatricsMedical Faculty of UMM RSML

2012


2/29

SOUTHEAST ASIAN J TROP MED PUBLIC HEALTHVol 41 No. 5 September 2010


3/29

To compare the newly revised dengueclassification system, which is divided into

several levels of severity, with the WHOclassification system for the identification

of severe cases with/ without unusual

manifestations.


4/29

In 2004 the incidence of dengue infection was so high, the governmentdeclared the situation as an outbreak of dengue infection

Dengue infection in Indonesia has increased from0.05 incidents per 100,000 population in 1968 to

35.19 per 100,000 population in 1998

Dengue: Guidelines for diagnosis, treatment, prevention and control. WHO, 2009.


5/29

Dengue virus (DENV)has four serotypes

It is a mosquito-bornesingle positive-strandedRNA virus of the familyFlaviridae; genus

Flavivirus All four serotypes can

cause the full spectrum

of disease


6/29

Dengue fever (DF) and

Dengue hemorrhagic

fever (DHF) occurbecause dengue virus

(DENV) invades the

human body throughmosquito bites.


7/29

People who have been infected with one serotypeof dengue virus, in general, have protection againstthat same serotype.

Protection against a different serotype only lasts ashort time after infection.

A second infection with a different serotype can

lead to dengue hemorrhagic fever.


8/29

Antibody dependent enhancement

(ADA) of infection is one of the mostimportant mechanism of pathogenesis

of dengue infection


9/29

Dengue infection presents as a clinical spectrum: asymptomatic, undifferentiated fever, DFand DHF

Classic DF symptoms include fever, headache, muscle pain, retroorbital pain and rash

The main characteristics of the dengue classification system include bleeding, plasma leakage,thrombocytopenia (platelet count 100,000/mm3), the presence of hypotension or narrowpulse pressure and clinical signs of shock, leading to the diagnosis of dengue shock syndrome

(DSS) (WHO, 1997)

The current dengue classification system is useful to identify cases of severe dengue infectionfor treatment and epidemiological surveillance

However, there can be varying clinical manifestations of dengue infection that do not fit thedefinitions of the World Health Organization (WHO).

One revised dengue classification system from DENCO (Dengue Control) has been studied inseveral countries in Asia and Latin America with good results


10/29

A prospective analytic observational study was conductedfrom October 2008 to July 2009 among dengue virusinfected pediatric patients at Dr.Soetomo Hospital,Surabaya, Indonesia.

Patients aged 0-13 years with suspected dengue virusinfection based on WHO diagnostic criteria were includedconsecutively in the study.

Exclusion criteria were patients with hematologicdisorders and severe heart or lung diseases.

Patients who did not meet WHO diagnostic criteria butwere clinically suspected to have dengue virus infectionwere included in the study.

The research team recorded the data on a standard datacollection sheet.


11/29

Diagnostic Procedure

Blood sampling was performed for serological tests (IgG and IgM anti-dengue), PCR and culture and isolation of the virus.

These examinations were performed on admission and at the time of

fever defervescence to confirm the diagnosis of dengue virus infection. Patients with one or more positive diagnostic tests were confirmed as

having dengue virus infection, whereas those with negative results wereexcluded.

Statistical Analysis

The data were analyzed to determine the ability of the classificationsystems to adequately classify the patient compared to the clinical course

Analyses were performed using SPSS 16.0,0, using the Mann- Whitneytest, then binary logistic regression was used to compare the twoclassification systems.

A p-value 0.05 was considered statistically significant


12/29

One hundred forty-five patients were studied, they consisted of 68 boys and 77 girls.The signs and symptoms of the patients at the time of admission varied, as can be

seen in table.


13/29

WHO 1997 CLASSIFICATION

122 cases (84.1%) were classified as

having nonsevere dengue infection :

70 patients (48.3%) with dengue fever (DF),

39 (26.9%) with dengue hemorrhagic fever(DHF) grade I

13 (9%) with DHF grade II.

Twenty-three cases (15.9%) were

classified as having severe dengue

infection :

16 patients (11%) with DHF grade III

7 (4.8%) with DHF grade IV.

Using clinical intervention, 8 cases

(6.6%) classified as being nonsevere

dengue infection using WHO criteria

were reclassified as severe (sen : 74%;

spes 100%)

DENCO CLASSIFICATION

117 cases (80.7%) were classifiedas having non-severe dengueinfection : 79 cases (54.5%) of dengue

infection without warning signs 38 cases (26.2%) of dengue

infection with warning signs. Twenty-eight cases (19.3%) were

classified as having severedengue infection.

Using clinical intervention, 4cases (3.4%) classified as havingnon-severe dengue infectionwere reclassified as havingsevere dengue infection (sen88% ; spes 99%)


14/29

Mann-Whitney test both the WHO classificationsystem (p=0.000, Z=7.385) and the new dengue

classification system (p=0.000, Z=8.993) were

equally good. Binary logistic regression the new dengue

classification system (p=0.000, Wald:22.446) was

better in detecting severe dengue virus infectioncases compared with the WHO classification system(p=0.175, Wald:6.339).


15/29


16/29

The new revised dengue classification systemhad a higher sensitivity and good specificity

Clinical information was obtained from nearly

2,000 patients with confirmed dengue,conducted in 7 countries from 2 continents. This study concluded that 18-40% of cases could

not be classified by the current WHOclassification system, and > 15% of cases withshock could not be classified as severe cases ofdengue, since they did not meet some of thecriteria of DHF/DSS


17/29

DENCO (dengue control) criteria can alsoidentify some signs and symptoms that occur

in patient 1 day before detorioration ofconditions. These warning signs allow early

identification of high risk dengue patientsallowing doctors a chance to begin earlytreatment by replacing fluids intravenouslyand improving the patientss prognosis.


18/29

In this study clinical interventions were used as a toolfor grading the severity of the disease.

There are 3 levels of severity according to clinicalintervention criteria : mild, moderate and severe.

There are 3 patient groups based on these criteria: group A (patient may be sent home/outpatient treatment)

group B (patient must be hospitalized for closeobservation and medical treatment),

group C (requiring intensive emergency treatment) In this study there were only 2 intervention groups:

moderate (group B, 114 patients) and severe (group C,31 patients) could be defined.


19/29


20/29

This study has some limitations :

Limited numbers of samples

Limited the comparative analysis betweenthese two classification systems

In this study, WHO standards guidelines

1997 were used for the management ofdengue infected patients.


21/29

This study shows the revised dengue

classification system may be better at

detecting severe dengue infection casescompared to the WHO classification

system.


22/29

Thank You > > >


23/29


24/29


25/29


26/29


27/29


28/29

Inhibition of interferon signalling byblocking signal transducer

NS4B

NS5

Inhibition of the Type-1 interferonresponse

NS2B3


29/29

journal reading - revised dengue classsification criteria

Documents