首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Dengue virus infection can cause mild dengue fever (DF) or severe dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Cytokines are believed to be involved in the pathogenesis of dengue infection. However, the role of the pro-inflammatory cytokine macrophage migration inhibitory factor (MIF) in dengue infection is unclear. In this study, serum levels of MIF in adult dengue patients with different disease severity and clinical outcome were determined and compared with the levels of other cytokines, tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), IL-10, and interferon gamma (IFN-gamma), in the same patients. Serum levels of MIF, IL-6, and IL-10, but not IFN-gamma or TNF-alpha, were higher in all DHF patients who died than in DHF survivors and DF patients. We conclude that in addition to IL-6 and IL-10, elevated levels of serum MIF are a potential predictor of disease severity and clinical outcome in dengue patients.  相似文献   

2.
Dengue is an arboviral disease and occurs in tropical countries where over 2.5 billion people are at risk of infection. Each year an estimated 100 million cases of dengue fever (DF) occur and between 2.5 and 5 lakh cases of dengue hemorrhagic fever (DHF) are reported to WHO. Severe thrombocytopenia and increased vascular permeability are two major characteristics of DHF. A study was conducted to note the relationship between the platelet counts and severity of the disease in pediatric cases of dengue fever. Platelet counts were found to be predictive as well as recovery parameter of DF/DHF/DSS.  相似文献   

3.
BACKGROUND: Clinical manifestations of dengue vary in different areas of endemicity and between specific age groups, whereas predictors of outcome have remained controversial. In Brazil, the disease burden predominantly affects adults, with an increasing trend toward progression to dengue hemorrhagic fever (DHF) noted. METHODS: A cohort of adults with confirmed cases of dengue was recruited in central Brazil in 2005. Patients were classified according to the severity of their disease. Associations of antibody responses, viremia levels (as determined by real-time polymerase chain reaction [PCR]), and serotypes (as determined by multiplex PCR) with disease severity were evaluated. RESULTS: Of the 185 symptomatic patients >14 years of age who had a confirmed case of dengue, 26.5% and 23.2% were classified as having intermediate dengue fever (DF)/DHF (defined as internal hemorrhage, plasma leakage, manifested signs of shock, and/or thrombocytopenia [platelet count, < or =50,000 platelets/mm3]) and DHF, respectively. The onset of intermediate DF/DHF and DHF occurred at a late stage of disease, around the period of defervescence. Patients with DHF had abnormal liver enzyme levels, with a >3-fold increase in aspartate aminotransferase level, compared with the range of values considered to be normal. Overall, 65% of patients presented with secondary infections with dengue virus, with such infection occurring in similar proportions of patients in each of the 3 disease category groups. Dengue virus serotype 3 (DV3) was the predominant serotype, and viremia was detected during and after defervescence among patients with DHF or intermediate DF/DHF. CONCLUSIONS: Viremia was detected after defervescence in adult patients classified as having DHF or intermediate DF/DHF. Secondary infection was not a predictor of severe clinical manifestation in adults with infected with the DV3 serotype.  相似文献   

4.
To assess the potential role of interleukin-6 (IL-6) in the pathogenesis of dengue virus infection, levels of this cytokine were measured in children with dengue virus infection on admission to the hospital. As presumed surrogate markers of IL-6, C-reactive protein (CRP) and secretory phospholipase A2 (sPLA2) were measured. Three groups were studied: 33 apparently healthy children as negative controls, 11 children with bacterial infections as positive controls, and 186 children with serologically documented dengue virus infection. One-hundred and fifteen patients had dengue fever (DF) and 71 had dengue hemorrhagic fever (DHF). Compared with healthy controls, dengue shock syndrome (DSS) patients had significantly higher levels of IL-6 on admission (P < 0.05), comparable with those in positive controls. Dengue patients with shock had significantly higher levels of IL-6 than normotensive patients (P < 0.001) and higher levels of IL-6 were associated with a higher incidence of ascites. C-reactive protein concentrations in dengue patients and in healthy children were not different, but lower than in children with bacterial infections (P = 0.008). Secretory phospholipase A2 levels were higher in dengue patients than in apparently healthy children (P < or = 0.05) and similar to those in children with bacterial infection. Dengue shock syndrome patients had significantly higher sPLA2 concentrations than normotensive patients (P = 0.02). These data indicate that IL-6 and sPLA2 may have a pathogenetic role only in the most severe forms of dengue virus infection.  相似文献   

5.
OBJECTIVES: Dengue haemorrhagic fever (DHF) is an important cause of morbidity in South-east Asia and used to occur almost exclusively in young children. In recent years, there has been a progressive shift in age-distribution towards older children and adults. We investigated an outbreak in 2001 in both children and adults, in an endemic area of Thailand. METHODS: Retrospective study of 347 patients with serologically confirmed dengue infection admitted to Chonburi Hospital during an epidemic in 2001. RESULTS: A total of 128 (37%) patients had dengue fever (DF) and 219 (63%) had DHF. Patients with DHF were significantly older than patients with DF (11 years vs. 8 years). Clinical bleeding was noted in 124 individuals, both with DF (n = 24) and DHF (n = 100), and significantly more frequently in adults. Twenty-nine (13.2%) of all DHF cases were caused by primary infection. Secondary dengue infection was associated significantly with the development of DHF in children, OR (95% CI) = 3.63 (1.94-6.82), P < 0.0001, but not in adults, OR (95% CI) = 0.6 (0.02-6.04), P = 1. Unusual clinical manifestations were observed in 23 patients: three presented with encephalopathy and 20 with highly elevated liver-enzymes. In the latter group, four patients were icteric and nine had gastrointestinal bleeding. CONCLUSION: These results indicate that DHF in South-east Asia is common in both children and adults. In dengue-endemic countries, dengue should be considered as a differential diagnosis in patients with clinical gastrointestinal bleeding in association with increased liver enzymes.  相似文献   

6.
Dengue fever (DF) and dengue hemorrhagic fever (DHF) are major public health problems in India. During the period following an epidemic, a study was carried out using virological and serological tests for confirmation of suspected cases of dengue virus infection in fever cases presenting to the All India Institute of Medical Sciences. Serum samples of suspected DF/DHF cases were processed from January to December 1997. In 37 samples from patients with fever of less than 5-day duration, received on ice, virus isolation was attempted in C6/36 clone of Aedes albopictus cell line, followed by indirect fluorescent antibody staining with monoclonal antibodies to dengue viruses 1 to 4. One hundred and forty-three serum samples from patients with more than 5 days fever were tested for dengue specific IgM antibody by either MAC-ELISA or a rapid immunochromatographic assay. Dengue virus type 1 was demonstrated by culture in 8 (21.6%) of 37 serum samples and IgM antibody could be detected in 42 (29.4%) of the 143 serum samples by the serological methods. The peak of dengue virus infection was seen from September to November 1997.  相似文献   

7.
To demonstrate the differences of clinical features and hematologic abnormalities between dengue fever (DF) and dengue hemorrhagic fever (DHF), 359 pediatric patients admitted St. Luke's Medical Center in Quezon City, between 1999 and 2001 in Metro Manila, and adjoining provinces the Philippines, with a laboratory-confirmed dengue virus infection were evaluated. One third of the patients had DHF, and most of these patients were without shock. Restlessness, epistaxis, and abdominal pain were more associated with DHF. The platelet count was significantly lower in the DHF group than in the DF group before and after defervescence. In the DHF patients, the hematocrit was significantly increased before defervescence, and decreased the day after due to administration of intravenous fluid. Coagulation abnormalities associated with most DHF patients were thrombocytopenia and an increased fibrinolysis, but not disseminated intravascular coagulation. We present recent data on readily obtained clinical and laboratory data that can be used for early diagnosis and consequently earlier appropriate treatment of dengue virus infections.  相似文献   

8.
Dengue fever infection was first documented in Jeddah, Saudi Arabia, by virus isolation of dengue type 2 virus in 1994 at the virology laboratory of Dr. Soliman Fakeeh Hospital. Dengue virus surveillance was established after that time. Blood samples were collected from 985 patients (710 male patients and 275 female patients) with suspected cases of dengue from February 1994 to December 1999. Dengue virus isolates were obtained in 207 patients (21%; 162 male patients and 45 female patients). Dengue type 2 was the predominant serotype (138 of 207 isolates, 66.7%), followed by dengue type 1 with (56 of 207 isolates, 27%) and dengue type 3 (13 of 207 isolates, 6.3%). The largest number of isolates (186 of 207 isolates, 90%) was in 1994, a year during which there was a dengue epidemic. In the next 5 years, 1995-1999, only 21 isolates (10%) were isolated. Immunoglobulin M capture enzyme-linked immunosorbent assay was positive in 160 acute samples; 52 of them were from virus culture-positive cases and 108 (11%) from culture-negative cases. The total number of cases diagnosed by both methods was 315 (32%). The prevalence of dengue immunoglobulin G antibodies, as assessed on the basis of immunofluorescent assay, hemagglutination inhibition titers > or = 1/20, or both, in the acute samples was 314 (32%) of 985, indicating past Flavivirus infection. Two patients died, one man with dengue hemorrhagic fever and one woman with dengue shock syndrome. Both fatal dengue cases were due to infection with type 2 virus. All other cases were simple dengue fever. To our knowledge, this is the first report confirming the circulation of 3 dengue serotypes in Jeddah.  相似文献   

9.
The objective of this study was to compare the clinical spectra of the dengue serotypes proven by the PCR technique. This retrospective study reviewed the clinical information of dengue-infected patients who were admitted to northeastern provincial hospitals in Thailand from June to September 2002. Dengue infection and viral serotypes were confirmed by polymerase chain reaction (PCR). Paired anti-dengue immunoglobulin G (IgG) and IgM from paired sera were analyzed by enzyme-linked immunosorbent assay (ELISA). Ninety-nine PCR-proven dengue-infected Thai patients were studied. Their ages ranged from 3-30 years. They were infected with DEN1, DEN2, DEN3 and DEN4 in 21, 55, 12, and 12%, respectively. Twenty-two percent had primary and 78% had secondary infections. Dengue fever was the most common presentation for both primary (77.2%) and secondary infections (46.7%). The ratios of dengue fever:dengue hemorrhagic fever (DF:DHF) and non-dengue shock syndrome:dengue shock syndrome (non-DSS:DSS) for DEN2 was the lowest of the dengue serotypes. There was no difference in the duration of fever, percentage of hepatomegaly and bleeding among the serotypes in both DF and DHF. The trends in the white blood cells, lymphocyte and atypical lymphocyte counts in DEN3 were the highest, while those of DEN1 were the lowest of the dengue serotypes.  相似文献   

10.
Emerging viral pathogens in long-term expatriates (II): dengue virus   总被引:2,自引:1,他引:2  
Dengue virus infections have been well known for many years; still dengue virus is regarded as an ‘emerging’ pathogen, as the disease profile is changing. Its geographical range and oveall incidence, and the incidence of the associated complications, dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS), are on the increse. Modern-day travel and increasing urbanization seem to be the main contributing factors. In order to estimate the risk of infection during long-term stays in dengue-endemic countries, we tested sera obtained from 323 development aid workers and their family members who had spent on average 9.8 years in dengue-endemic regions for the presence of dengue virus antibodies. Dengue virus antibody screening was done by a commercially available immunofluorescence test (IF). Reactive samples were re-tested by an in-house IF and also tested for cross-reactivity to yellow fever virus using yellow fever IF and neutralization test (NT). Evaluation of the results revealed that the screening test has a specificity of at least 63.2%. In 12 of 19 initially positive cases crossreacting antibodies against yellow fever virus could be ruled out. Three cases remained indeterminable, whereas four of the reactive and 10 (out of 12) of the borderline reactive cases showed crossreactivity with yellow fever virus, probably due to previous vaceination. We found seroprevalence rates of 4.3% with no significant differences related to gender or area of upbringing. Scroprevalence rates were evaluated according to region of suspected or confirmed infection. In two cases the dengue infection had taken a classical clinical course; in another three cases an extraordinary febrile illness was reported in the history. None of the other seropositive individuals had a history of an illness possibly attributable to dengue virus infection. Our results show that there definitely is a risk for long-term expatriates to acquire (mostly non- or oligo-symptomatic) dengue infection, which might be important especially in the light of the supposed aetiology of DHF or DSS as a secondary infection with another dengue virus serotype.  相似文献   

11.
Dengue fever (DF) and dengue haemorrhagic fever (DHF) are caused by the dengue virus. The major pathophysiological hallmark that distinguishes DHF from DF is plasma leakage as a result of increased vascular permeability. Following this leakage, hypovolaemic shock occurs as a consequence of a critical plasma volume loss. Constant haematological abnormalities occurring in DHF and frequently include bone marrow suppression, leucopenia and thrombocytopenia. An enhanced immune response of the host to a secondary DV infection is a feature of DHF and leads to many consequences. These are immune complex formation, complement activation, increased histamine release and a massive release of many cytokines into the circulation, leading to shock, vasculopathy, thrombopathy and disseminated intravascular coagulation (DIC).The mechanisms underlying the bleeding in DHF are multiple. These are vasculopathy, thrombopathy and DIC. Thrombopathy consists of thrombocytopenia and platelet dysfunction. DIC is prominent in patients with shock. The most severe DIC and massive bleeding are the result of prolonged shock and cause a fatal outcome. The mechanisms of thrombopathy and DIC and the proper management of DHF are reviewed and discussed.  相似文献   

12.
Dengue illness has been a major health concern in Pakistan during the last decade. Dengue infection can result in a spectrum of clinically distinct outcomes, ranging from asymptomatic infection to potentially life-threatening forms of dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). A single-nucleotide polymorphism in FcγRIIa (rs1801274) results in altered affinity of the receptor for different subclasses of immunoglobulin G, and is a key player in determining the susceptibility to or protection from severe clinical infection of dengue. In this study, we analyzed the allelic and genotypic distribution of rs1801274 in subjects of Pakistani origin with subclinical dengue infection (n = 40), dengue fever (DF) (n = 40), and DHF/DSS (n = 30). We found that HH homozygotes and heterozygotes were significantly more likely to develop clinical dengue (odds ratio [OR] = 3.21, 95% confidence interval [CI] = 1.29–7.97, P = 0.009), either DF (OR = 2.82, 95% CI = 1.00–7.97, P = 0.045) or DHF/DSS (OR = 3.90, 95% CI = 1.13–13.07, P = 0.024) than the asymptomatic dengue infection. Results of allelic distribution comparisons and logistic regression analysis also supported the same relationship. The results suggest complex nature of interacting factors in determining the course for severe dengue illness.  相似文献   

13.
OBJECTIVES: Oxidative stress in dengue viral infection has been suggested and severity of it was found to be associated with progress of illness. Hence assessing oxidative stress mediated changes in plasma proteins can be an early biomarker for prediction of severe dengue infection. DESIGN AND METHODS: Thirty two dengue hemorrhagic fever (DHF), 21 dengue shock syndrome (DSS), 27 dengue fever (DF) and 63 age and sex matched controls, were included in this study. Blood samples were collected on the 3rd day of fever. Protein carbonylation (PCOs) and protein-bound sulphydryl (PBSH) group levels were determined by spectrophotometric method and analyzed as predictor of dengue hemorrhagic fever and dengue shock syndrome. RESULTS: About 80-84% of cases presented with no signs of DHF/DSS at the time of sampling. Dengue infected individuals had significantly elevated PCOs and low PBSH group levels than the controls. Using one-way ANOVA we found a significant difference with high PCOs and low PBSH group levels between DHF and DSS when compared with DF (P<0.001). However, no difference was observed in PBSH group levels between DHF and DSS. A significant difference in PCOs to PBSH ratio was observed among DF, DHF and DSS (P<0.001). Linear regression analysis revealed that duration of hospitalization is dependent on PCOs and PBSH group levels. Receiver operator curve (ROC) analysis indicated that 5.22nmol/mg protein PCOs; 1.08 PCOs to PBSH group levels ratio were optimal cutoff value for predicting DHF with sensitivity and specificity of 87.5% and 74.1%; 96.9% and 81.5%, respectively. For DSS prediction, 6.13 nmol/mg protein PCOs; 1.16 PCOs to PBSH group levels ratio were found as effective cutoff with sensitivity and specificity of 81% and 71.9%; 95.2% and 56.2%, respectively. CONCLUSION: Oxidative stress has been observed to develop since early days of onset of dengue infection. Plasma PCOs, PCOs to PBSH group ratio were found to very well predict DHF/DSS.  相似文献   

14.
OBJECTIVE: Isolation of dengue virus from dengue fever and dengue haemorrhagic fever cases from Mindanao, Republic of the Philippines. METHODS: 12 patients with clinically suspected dengue fever (DF) or dengue haemorrhagic fever (DHF) presenting in four regional hospitals between August and September 1995 on Minadano were enrolled in the study. Dengue virus was isolated by inoculation of Vero/E6 or C6/36 cells with patient serum. IgM antibodies were measured using a commercial test system. Up to 454 bp of the capsid region and 240 bp of the E/NS1 gene junction of different viral isolates were sequenced and phylogenetically analyzed. RESULTS: Virus could be isolated from seven patients, five isolates were typed as dengue virus type 2 and two as dengue virus type 4 by immunostaining with monoclonal antibodies or by RT/PCR. Phylogenetic analysis confirmed a close relationship of the dengue virus type 2 isolates with viruses isolated in the Philippines in 1983 and 1988. CONCLUSION: As observed in studies from other parts of South East Asia, dengue virus type 2 was readily isolated from dengue haemorrhagic fever cases. Dengue virus type 2 and 4 circulate in Mindanao, Philippines, with dengue type 2 being responsible for most of our severe DF or DHF cases.  相似文献   

15.
BACKGROUND: Dengue is a mosquito-borne viral infection endemic throughout the tropics and subtropics. The global prevalence of dengue has grown dramatically in recent years and it has been recognized as a potential hazard to tourists. OBJECTIVE: In this study, we analyzed the epidemiology, clinical manifestations, laboratory features and serological/virological results in a series of German travellers returning to Berlin with acute dengue virus infection. STUDY DESIGN: Laboratory-confirmed dengue virus infections among German travellers returning to Berlin were studied retrospectively during the period of 1993-2001. Seventy-one patients tested positive for dengue fever and were included in this study. RESULTS: The majority of patients (77.5%) contracted the disease in South Central and South East Asia. The most important clinical characteristics were fever and prostration (100%), headache, predominantly frontal or retroorbital (86%), arthralgia (79%), morbilliform rash (66%) and myalgia (48%). The most meaningful laboratory results were: marked leucopenia (72%), thrombocytopenia (70-89%), hyponatremia (41%) and increased hepatic enzymes ALAT (41%), ASAT (45%) and LDH (62%). Dengue virus infection was diagnosed by means of a matching clinico-epidemiological history and positivity of specific serology and/or virus isolation. Hemorrhagic phenomena appeared in 10 of the 71 patients (14%), out of which one was diagnosed with DHF according to WHO criteria. All patients recovered fully. CONCLUSION: Pretravel advice should be given to all travellers to dengue-endemic areas. DF must be included in the differential diagnosis of patients returning febrile from tropical areas.  相似文献   

16.
Human immune responses to dengue viruses   总被引:3,自引:0,他引:3  
Dengue fever (DF) and dengue hemorrhagic fever (DHF)/dengue shock syndrome (DSS) are major public health problems in many areas of the world. We are analyzing the human immune responses to dengue viruses, in order to understand the mechanism of recovery from dengue virus infections and the pathogenesis of DHF/DSS. Human natural killer (NK) cells lyse dengue virus-infected cells to a greater degree than uninfected cells. Antibodies to dengue viruses augment the lysis of dengue virus-infected cells by NK cells. Dengue virus-infected monocytes produce high levels of interferon alpha (IFN alpha). DR+ lymphocytes also produce high levels of IFN alpha after contact with dengue virus-infected monocytes. The IFN alpha produced protects uninfected monocytes from dengue virus infection. These results suggest that NK cells and IFN alpha may play an important role in controlling primary dengue virus infection. Dengue virus-specific CD4+CD8(-)T lymphocytes and CD4(-)CD8+T lymphocytes are present in the peripheral blood mononuclear cell population from donors who were infected with dengue virus. Most of CD4+T lymphocytes are dengue serotype-crossreactive. They lyse dengue virus-infected autologous cells in an HLA class II-restricted fashion, and produce interferon gamma (IFN gamma). IFN gamma augments dengue virus infection of monocytic cells in the presence of antidengue virus antibodies by increasing the number of Fc gamma receptors. Dengue virus-specific CD8+T lymphocytes lyse dengue virus-infected autologous cells in an HLA class I-restricted fashion. These CD8+T lymphocytes are also dengue serotype-crossreactive.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

17.
BACKGROUND: Dengue fever has seen a significant re-emergence in Southeast Asia. Associated with the rise of dengue has been the increase in dengue-associated mortality. To better understand the predictors of mortality, we conducted a review of hospitalized adult dengue infections within our institution. METHODS: This was a retrospective case-control study of dengue-associated deaths at a large tertiary care hospital. RESULTS: In 2004, of 3186 cases of dengue fever (DF)/hemorrhagic dengue fever (DHF) admitted to our institution, there were 130 cases of DHF and seven dengue-associated deaths (case-fatality rate 5.4%). At least three of the seven fatal cases had serological evidence of primary dengue infection. All dengue-mortality cases had rapidly progressive clinical deterioration at an average of day 4 of fever with intensive care admission occurring on a mean of 5.6 days of fever. Adult respiratory distress syndrome, disseminated intravascular coagulopathy, and multi-organ failure were the most common causes of death despite early hospitalization, intravenous fluid, and blood-product support. CONCLUSION: Dengue is associated with severe disease, and deaths do occur despite current supportive management. Fatal DHF/dengue shock syndrome (DSS) does occur in adults and in primary dengue infection. Better early predictors of disease severity and clinical interventions are needed.  相似文献   

18.
Dengue fever (DF) may present as uncomplicated dengue fever, dengue hemorrhagic fever (DHF), or dengue shock syndrome (DSS). Transient intense viremia is responsible for mild, moderate, or severe hepatic dysfunction. Our aim was to evaluate the spectrum of hepatic dysfunction and evidence of plasma leakage in different stages of dengue fever in this epidemic. Detailed history, physical examination, and laboratory evaluation of 1,226 serologically proved dengue patients. Patients with DF were 170 and DHF was 1,056, among which those with ALT ≥?75 U/L were 43 and 570, respectively. Patients with ALT >?151–300, >?300–450, and >?450 U/L were 186, 77, and 34, respectively. Affected DF (n?=?43) and DHF (n?=?570) patients presented with symptoms and signs similar to viral hepatitis, but ascites, pleural effusion, raised INR, bleeding, and hypoalbuminemia were present only in DHF patients. In dengue fever, there was a wide range of hepatic dysfunction mimicking acute viral hepatitis.  相似文献   

19.
Objective: To review the management experience of a consecutive series of patients presenting as acute surgical abdomen whom were ultimately diagnosed to have DF(Dengue fever)/ DHF(Dengue heamorrhagic fever),Methods: Clinical data of all cases of apparent acute abdomen(AA) which were later confirmed as having DF/DHF reviewed by two surgical units from December 2012 to December 2013 were analyzed,Initially confirmed patients with DF/DHF who developed abdominal symptoms were not considered,Results: Out of the seventeen cases(7 males,age range 10-71 years) presented with fever and AA; appendicitis,cholecystitis,pancreatitis and non-specific peritonitis were suspected initially in 8,5,1 and 3 cases,respectively,Neutropenia or thrombocytopenia signifying DF/DHF occurred only in 11 patients at first evaluation thus six remained as surgical candidates beyond 24 h,One patient underwent appendicectomy with a prolonged hospital stay,DF was confirmed by serology in all patients,latest by fourth day of admission,One required blood product transfusion,4 needed critical care treatment and there was 1 death,Conclusions: DF/DHF misleads the clinicians when it presents as AA,Initial heamatological and ultrasonographic findings may be equivocal creating a diagnostic and management dilemma,Vigilant clinical suspicion and early dengue serological assessment is advisable in equivocal cases of AAs with fever in dengue endemic areas,to confirm/exclude the infection in order to avoid unnecessary surgical morbidity in the presence of DF.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号