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Dengue haemorrhagic fever
Updated by Charles Gomersall, May 2008
- Severe form of dengue fever
- 0.25-0.5 million cases per year
- 24,000 deaths per year
Epidemiology
- 4 serotypes
- Some cross immunity. Infection with one serotype produces lifelong
immunity to that serotype but only a few months immunity to other serotypes
- Aedes aegypti mosquito is principal vector although disease can be
transmitted by other mosquitos
- Wide geographical
distribution
- Risk factors for severe disease:
- child
- female
- chronic disease eg asthma, diabetes
- Caucasian
- longer time interval between primary and secondary infection
Clinical features
Dengue haemorrhagic fever is distinguished from dengue by
the presence of increased vascular permeability not by the presence of
haemorrhage. Secondary infections (particularly with serotype 2) are more likely
to result in severe disease and dengue haemorrhagic fever however in a large
series of patients from India none of the patients admitted to ICU gave a
history of previous dengue fever.
Dengue fever
Clinical criteria for
diagnosis: acute illness with ³2
of:
- Headache
- Retro-orbital pain
- Myalgia
- Arthralgia
- Rash
- Haemorrhagic manifestations
- Leucopaenia
- Rare presentations include:
- Severe haemorrhage
- Jaundice
- Parotitis
- Cardiomyopathy
- Mononeuropathies, polyneuropathies
- Encephalitis
- Transverse myelitis
Criteria for the diagnosis of dengue haemorrhagic fever
-
Haemorrhagic features
-
Petechiae, ecchymoses, purpura
-
Mucosal bleeding
-
GI bleeding
-
Bleeding from puncture sites
-
Platelets <100,000/ml
-
Objective evidence of capillary leak:
-
Fluctuation of packed cell volume by ³20%
during course of illness and recovery
-
OR clinical signs eg pleural effusion, ascites
or hypoproteinaemia
Criteria for dengue shock syndrome
- Pulse pressure <20 mmHg OR
- Systolic BP <90 mmHg (in patients ³5
years)
Investigations
- Neutropaenia
- Lymphocytosis
- Thrombocytopaenia
- Raised liver enzymes
Probable diagnosis
At least one of:
-
Supportive serology on single sample
-
Haemagglutination inhibition test titre ³1280
or
-
Comparable IgG titre with ELISA or
-
IgM positive
-
Occurrence at same location and time as confirmed
cases of dengue fever
Definite diagnosis
At least one of:
- Isolation of dengue virus from serum
- ³4
fold increase in IgG titre (by haemagglutination inhibition test)
- Increase in titre of IgM
- Detection of dengue virus in tissue, serum or CSF by immunohistochemistry,
immunfluorescence or immunosorbent assay
- Detection of dengue by PCR
Differential diagnosis
Complications
- abdominal compartment syndrome (associated with high mortality)
Treatment
- No specific therapy
- Avoid aspirin and NSAIDs because of increased risk of Reye’s syndrome
and haemorrhage
Prognosis
- 11% mortality amongst a group of patients admitted to ICU with
severe bleeding, persistent vomiting and
shock. However, as many patients were refused admission to ICU this was a
selected group and the outcome may not be a true reflection of prognosis
Further reading
Amin
P et al. Dengue, dengue haemorrhagic fever, dengue shock syndrome.
www.cdc.gov/ncidod/dvbid/dengue/
Guzman MG, Kouri G. Dengue diagnosis,advances and challenges.
Int J Infect Dis 2004; 8:69-80 Chandralekha et al. The
north Indian dengue outbreak 2006: a retrospective analysis of intensive care
unit admissions in a tertiary care hospital. Transactions of the Royal Society
of Tropical Medicine and Hygiene, 2008; 102:143-147 |
