[Show abstract][Hide abstract] ABSTRACT: Dengue has become a global public health problem and a sensitive diagnostic test for early phase detection can be life saving. An internally controlled, generic real-time PCR was developed and validated by testing serial dilutions of a DENV positive control RNA in the presence of a fixed amount of IC with results showing a good linearity (R(2) = 0.9967) and a LOD of at least 1.95 × 10(4) copies/mL. Application of the generic PCR on 136 patient samples revealed a sensitivity of 95.8% and specificity of 100%. A newly developed multiplex real-time PCR with serotype-specific probes allowed the serotyping of DENV for 80 out of 92 (87%) generic real-time PCR positive patients. Combined these real-time PCRs offer a convenient diagnostic tool for the sensitive and specific quantification of DENV in clinical specimens with the possibility for serotyping.
Full-text · Article · Dec 2011 · Advances in Virology
[Show abstract][Hide abstract] ABSTRACT: Fever is a common reason for attending primary health facilities in Vietnam. Response of health care providers to patients with fever commonly consists of making a presumptive diagnosis and proposing corresponding treatment. In Vietnam, where malaria was brought under control, viral infections, notably dengue, are the main causes of undifferentiated fever but they are often misdiagnosed and inappropriately treated with antibiotics.This study investigate if educating primary health center (PHC) staff or introducing rapid diagnostic tests (RDTs) improve diagnostic resolution and accuracy for acute undifferentiated fever (AUF) and reduce prescription of antibiotics and costs for patients.
In a PHC randomized intervention study in southern Vietnam, the presumptive diagnoses for AUF patients were recorded and confirmed by serology on paired (acute and convalescence) sera. After one year, PHCs were randomized to four intervention arms: training on infectious diseases (A), the provision of RDTs (B), the combination (AB) and control (C). The intervention lasted from 2002 until 2006.
The frequency of the non-etiologic diagnosis "undifferentiated fever" decreased in group AB, and - with some delay- also in group B. The diagnosis "dengue" increased in group AB, but only temporarily, although dengue was the most common cause of fever. A correct diagnosis for dengue initially increased in groups AB and B but only for AB this was sustained. Antibiotics prescriptions increased in group C. During intervention it initially declined in AB with a tendency to increase afterwards; in B it gradually declined. There was a substantial increase of patients' costs in B.
The introduction of RDTs for infectious diseases such as dengue, through free market principles, does improve the quality of the diagnosis and decreases the prescription of antibiotics at the PHC level. However, the effect is more sustainable in combination with training; without it RDTs lead to an excess of costs.
Full-text · Article · Sep 2010 · BMC Health Services Research
[Show abstract][Hide abstract] ABSTRACT: To investigate the proportion of viral respiratory tract infections among acute undifferentiated fevers (AUFs) at primary health facilities in southern Vietnam during 2001-2005, patients with AUF not caused by malaria were enrolled at twelve primary health facilities and a clinic for malaria control program. Serum was collected on first presentation (t0) and after 3 weeks (t3) for serology. After exclusion of acute dengue infection, acute and convalescent serum samples from 606 patients were using enzyme-linked immunoassays to detect IgA, as well as IgM and IgG antibodies against common respiratory viruses. Paired sera showed the following infections: human parainfluenza virus (HPIV, 4.7%), influenza B virus (FLUBV, 2.2%), influenza A virus (FLUAV, 1.9%) and human respiratory syncytial virus (HRSV, 0.6%). There was no association between type of infection and age, sex or seasonality; some inter-annual differences were observed for influenza. Antibody prevalence, indicative of previous infections, was relatively low: HPV, 56.8%, FLUBV, 12.1%; FLUAV, 5.9% and HRSV, 6.8%.
Full-text · Article · Sep 2010 · The Southeast Asian journal of tropical medicine and public health
[Show abstract][Hide abstract] ABSTRACT: This study was performed to test the hypothesis that there are 'hotspots', i.e. geographical heterogeneity, of dengue transmission. Data from two repeat serosurveys in two villages in Vietnam were used to identify incident infections and to relate these to prevalence at baseline and thus assess geographical heterogeneity, i.e. clustering, in dengue transmission. A total of 400 households were surveyed; serological data from 521 children at baseline and from 119 children at follow-up were included in a spatial analysis. Geographical heterogeneity of dengue transmission was explored using a permutation null distribution test. This showed for the first time evidence of clustering of dengue virus transmission at the household level in asymptomatic children. Risk areas could be identified by seroprevalence surveys combined with mapping. Control of dengue virus transmission could be supported by identification and control of hotspots.
No preview · Article · Sep 2009 · Epidemiology and Infection
[Show abstract][Hide abstract] ABSTRACT: Diagnosing dengue in febrile patients is challenging. Of a total of 459 patients with acute undifferentiated fever, randomly selected from 12 primary health facilities and 1 clinic of the provincial malaria station in southern Vietnam, dengue-specific antibody (Ab) and NS1Ag enzyme-linked immunosorbent assay (ELISA) (Platelia, Bio-Rad Laboratories, Hercules, CA 94547, US) were performed on acute (t0) and convalescent (t3 weeks) sera. Polymerase chain reaction (PCR) was used for confirmation. Based on a composite of the NS1Ag-ELISA, Ab-ELISA, and PCR results, 54 (12%) patients had acute dengue. Positive and negative predictive values were 65% and 98% for the Ab-based diagnosis and 91% and 92% for NS1Ag, respectively. The agreement between Ab- and NS1Ag-based diagnosis was poor (kappa value, 0.2). Two patients without dengue had detectable NS1Ag on t0 and t3, 1 just above the cutoff value and 1 with very high values. For 5 dengue patients, NS1Ag was still detectable at very high levels at t3. Dengue NS1Ag can be used for early diagnosis of dengue; infrequent false-positive results need further clarification.
Full-text · Article · Mar 2009 · Diagnostic microbiology and infectious disease
[Show abstract][Hide abstract] ABSTRACT: To look for risk factors for dengue and community participation in dengue control in Binh Thuan Province, Vietnam, three communes with a low incidence of dengue and three with a high incidence, in Binh Thuan Province, were compared. Knowledge, perception and preventive practice of dengue were measured by means of a structured questionnaire. A check list of environmental observations was used to evaluate environmental factors. Focus group discussion was conducted to evaluate perceptions of key factors for dengue vector control and community participation. One hundred ninety households in 6 communes were included in the study. Several statistically significant differences between low and high incidence communities were identified. The factors associated with a higher risk of dengue fever on the logistic regression were occupation (farmer) (RR 7.94; 95% CI 2.29-27.55), number of children less than 15 years old in the household (RR 1.54; 95% CI 1.06-2.23), no experience with dengue fever in the household (RR 2.334; 95% CI 1.12- 4.88), a garden near the house (RR 2.22; 95% CI 1.18-4.17) and water containers having mosquito larvae (RR 1.64; 95% CI 1.02-2.62). Television was the most important source of information. There were differences in risk factors for dengue among communes with low and high incidences. Communication regarding dengue prevention should be improved in high incidence communes. Community participation in dengue vector control should be promoted to make the dengue control programs more efficient with greater coordination of resources.
Preview · Article · Feb 2008 · The Southeast Asian journal of tropical medicine and public health
[Show abstract][Hide abstract] ABSTRACT: Nutrition transition is one of the driving forces of the upcoming global epidemic of diabetes mellitus and cardiovascular diseases. We hypothesized that in previously deprived rapidly changing regions, the progress of the obesity epidemic is clustered per community and that screening with anthropometric school surveys can detect the negative effects of the nutrition transition in its early stages. In 16 different rural and urban communities in Binh Thuan Province, southern Vietnam, anthropometric surveys were conducted in local primary schools. Anthropometry of 2613 children showed a significant difference of the prevalence of wasting, stunting, and overweight between urban and rural communities. During the transition from high stunting rates to overweight, communities pass through an episode with dual burden of both conditions at different pace. Anthropometry of primary school children can reveal inter-community differences and identify the early stages of the nutrition transition.
Full-text · Article · Feb 2008 · Asia Pacific Journal of Clinical Nutrition
[Show abstract][Hide abstract] ABSTRACT: Dengue is highly endemic in Binh Thuan province, southern Viet Nam. To quantify the dengue-attributable disease burden in Binh Thuan, data from different sources was compiled. In 2003, 688 220 patients consulted 112 public primary health facilities. A total of 86 449 patients had fever, of whom 7399 (8.6%, 95% Cl 8.4-8.8) were booked without classifying diagnosis; this corresponds to 7.7 per 100 person years. Serological diagnosis confirmed that dengue contributed to approximately one quarter of all undifferentiated fevers presented to the public primary health facilities. The annual incidence of acute primary and secondary dengue among the total population was substantially higher and estimated to range from 5.5 to 11.1 per 100 person years. The number of notified cases of dengue in 2003 was only 527 cases, less than 1% of the total incidence of dengue.
[Show abstract][Hide abstract] ABSTRACT: Dengue is a common cause of fever in the tropics but its contribution to the total burden of febrile illnesses that is presented to primary health facilities in endemic regions such as Vietnam, is largely unknown. We aimed to report the frequency of dengue as a cause of fever in Binh Thuan Province, to describe the characteristics of dengue patients, and analyze the diagnostic accuracy of the health care workers and the determinants of the diagnostic process.
All patients presenting with acute undifferentiated fever at twelve community health posts and one clinic at the provincial malaria station, Binh Thuan Province, a dengue endemic province in southern Vietnam, were included. Record forms were used to fill in patient and diseases characteristics, pre-referral treatment, signs and symptoms, provisional diagnosis and prescribed treatment, referral and final outcome. Serum samples were collected at first presentation and after 3 weeks for serologic diagnosis.
2096 patients were included from April 2001 to March 2002. All 697 patients with paired serum samples were tested for dengue virus IgM and IgG. Acute dengue was found in 33.6% cases and past dengue virus infections were found in 57.1% cases. Acute primary infections were more common among children under 15 years old than among adults (7.7% vs. 3.5%, p value < 0.001). Younger age significantly predicted acute dengue (RR per increasing year of age (95 % CI): 0.986 (0.975-0.997, p value = 0.014). 48.9% of cases with clinical diagnosis of acute dengue were serologically confirmed and 32.5% of cases without clinical diagnosis of acute dengue were positive by serology after all (OR = 1.981, p value 0.025, 95% CI: 1.079-3.635). Tourniquet test was not a predictor for dengue diagnosis.
Dengue is responsible for one third of the fevers presented to the public primary health services in Binh Thuan, southern Vietnam. It presents as a highly unspecific illness and is hardly recognized as a clinical entity by primary physicians.
[Show abstract][Hide abstract] ABSTRACT: To describe the characteristics of patients consulting commune primary healthcare posts for acute undifferentiated fever not being malaria (AUF), and to explore the diagnostic and therapeutic responses of the healthcare workers.
All patients presenting with AUF at 12 commune health posts and one clinic at the provincial malaria station, Binh Thuan, a dengue endemic province in southern Vietnam, were included. Record forms were used to fill in patient and diseases characteristics, pre-referral treatment, signs and symptoms, provisional diagnosis and installed treatment, referral and final outcome.
Two thousand ninety-six patients were included from April 2001 to March 2002. The median delay to attend the health posts was, 0.87 day for > 5, 1.15 days for children aged 5-15 years and 1.41 days for adults (P < 0.001). Sixty-five per cent of patients took some measures before consulting the health post, of whom 82% applied self-medication and 69% took antibiotics. Pre-referral medication with antibiotics increased with age (RR 1.012 per year of age; 95% CI: 1.004-1.019). The diagnostic and therapeutic response of healthcare workers was very unspecific. The tourniquet test was inappropriately used as general discriminating test, not only for detecting dengue haemorrhagic fever. Empiric antibiotic therapy was installed in 77.2% of cases.
Management of uncomplicated fever, not being malaria, at the primary healthcare level in Vietnam is non-specific, dominated by searching signs of hemorrhagic dengue and empiric antibiotic treatment. This can probably be improved by better education.
Full-text · Article · Jul 2006 · Tropical Medicine & International Health
[Show abstract][Hide abstract] ABSTRACT: Early diagnosis and treatment of malaria (EDTM) is a key component of malaria control. The success of EDTM depends on health seeking behaviour and the quality of the health service. This study assessed self-diagnosis, treatment and treatment delay after the introduction of EDTM in 1993. In southern Vietnam EDTM comprises microscopic diagnosis and free treatment with artemisinin derivatives at public health facilities. Until 2001, 1698 questionnaires had been completed by patients participating in randomized treatment trials of uncomplicated malaria. The presumptive self diagnosis 'malaria' increased from 68% in 1993 to 100% in 2001 and self-treatment decreased, from 74% to 8% in 2000 and 24% in 2001. The median (maximum) delay between first symptoms and seeking treatment at a public health facility decreased from 3 (23) to 1.3 (3) days (P<0.001) Concomitant was a significant decline of reported incidence of malaria-associated mortality, severe malaria and uncomplicated malaria. If offered an attractive package of EDTM, patients become sensitized to the possibility of malaria and less likely to self-treat. EDTM should be provided as soon as possible to all symptomatic patients, aiming at reducing treatment delay to a maximum of 2 days.
Full-text · Article · Sep 2005 · Tropical Medicine & International Health
[Show abstract][Hide abstract] ABSTRACT: To study whether control of malaria leads to catch-up growth or an increase of obesity in a marginally nourished population.
A Vietnamese ethnic minority commune in southern Vietnam.
Repeated annual anthropometric surveys were performed from 1995 to 2000. Z-scores for height, weight and BMI for age and weight-for-height were determined by using NCHS 1978 and CDC 2000 reference tables and by the LMS method.
Active malaria control that reduced the parasite carrier rate from 50% in 1994 to practically nil in 1998.
Inhabitants were generally of short stature and very thin. Using the US reference tables, the prevalence of moderate/severe stunting among children was 53/24% and of wasting 27/9% in the first survey in 1995. Physical condition and normal daily activities of most inhabitants were normal. The repeated LMS-Z-scores uncovered a significant recovery of stunting, extending into preadolescence, including the development of a pubertal growth spurt for girls and enhancement of pubertal growth in boys, after control of malaria. The mean (95% CI) annual increase of Z-height-for-age was 0.11 (0.09-0.12) for boys and 0.14 (0.13-0.15) for girls (P<0.001). As a consequence, weight-for-age and BMI Z-scores decreased without indication of developing obesity.
Catch-up growth, extending into preadolescent age, was observed in a Vietnamese ethnic minority population with a chronic state of low food intake, without indication of developing obesity. The control of malaria was probably the most significant contribution to this catch-up growth.
Full-text · Article · Aug 2005 · European Journal of Clinical Nutrition
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to determine the prevalence of anemia and evaluate the relationship of malaria and helminth infections on anemia status in Phan Tien village, a mountainous ethnic minority community in southern Vietnam. This longitudinal study was performed from April 1997 to 2000 by measuring the hemoglobin concentration of 2,767 people who participated in six annual surveys at the end of the rainy seasons. Ferritin concentration was measured in 2000 to evaluate the proportion of iron deficiency anemia. The relation between malaria and intestinal helminth infections with anemia was investigated. Anemia was always over 43% and mainly associated with iron deficiency (80.1%). Using generalized estimating equations, a small but significant decline of the anemia prevalence was detected (OR: 0.805; p < 0.0001). Malaria was significantly associated with anemia (OR: 2.408; p = 0.0006). There was no significant effect of the control of intestinal helminth infections on the time course of anemia (95% CI: -0.1548 to 0.1651).
Full-text · Article · Jul 2005 · The Southeast Asian journal of tropical medicine and public health
[Show abstract][Hide abstract] ABSTRACT: A program to control intestinal helminth infections, based on stool surveys, mass treatment of children below 17 years, improvement of sanitation and health education was performed between 1997 and 1999 in Phan Tien, an ethnic minority community in mountainous southern Vietnam. Before intervention, 28.6% of children excreted eggs of at least one parasite, hookworm being the most common (23%), followed by Trichuris trichiura (1.9%), Hymenolepis nana (1.9%), Enterobius vermicularis (0.9%), Ascaris lumbricoides (0.5%), and multiple kinds of helminthes (0.5%). Strongyloides stercoralis was never detected. Poor sanitation and personal hygiene, and walking barefoot were considered the main risk factors for intestinal helminth infections. The success of 400 mg albendazole single dose mass treatment was initially frustrated by the poor quality of the drug formulation used, only containing half of the indicated amount of albendazole. Using another formulation quickly reduced the hookworm infection rate. Praziquantel was used to treat H. nana infections. After three years of intervention, intestinal helminth infections were reduced to 3.3% (p<0.0001). We conclude that interventions combining health education, improvement of sanitation and mass treatment effectively control intestinal helminth infections, but the quality of the drugs used is an important factor.
Full-text · Article · May 2005 · The Southeast Asian journal of tropical medicine and public health
[Show abstract][Hide abstract] ABSTRACT: Leptospirosis, although ubiquitous and potentially lethal, is often not diagnosed. The seroprevalence of anti-Leptospira antibodies and the utility of two rapid tests for the serodiagnosis of the disease were studied in Binh Thuan, an area in southern Vietnam with favourable conditions for Leptospira. In an initial survey, blood samples from 44 patients with undifferentiated fever and 83 healthy subjects were each examined for anti- Leptospira antibodies using three tests: an ELISA; a latex card-agglutination test (Dri Dot); and a lateral-flow assay (LeptoTek Lateral Flow). In the ELISA, samples from 35% of the healthy subjects and 40% of the febrile patients were found to have titres of anti- Leptospira IgM of at least 1:80. Only one of the 13 patients checked again, in ELISA, 3 weeks later, showed the marked increase in IgM titre that is indicative of acute leptospirosis. In the initial survey, although the positive results of the lateral-flow assay, applied to whole blood and serum, showed a good agreement with those of the ELISA (kappa = 0.743), the results of the lateral-flow assay were often indeterminate. The card-agglutination test was more specific. The overall agreement between the results of the rapid tests and those of the ELISA was generally poor. When the samples classified as 'indeterminate' in the lateral-flow assay were considered positive, the maximum kappa-value for this assay applied to whole blood was only 0.512. In conclusion, it appears that high seroprevalences of anti- Leptospira IgM and low incidences of acute leptospirosis limit the diagnostic value of the rapid tests that were investigated. The lateral-flow assay is not specific enough. The card-agglutination test is possibly better but, because of the low incidence, its sensitivity could not be evaluated adequately in the present study.
Full-text · Article · Jan 2005 · Pathogens and Global Health
[Show abstract][Hide abstract] ABSTRACT: To study the efficacy, tolerance, population pharmacokinetics and pharmacodynamics of artesunate followed by mefloquine at various intervals, 360 patients with Plasmodium falciparum malaria received 4 mg/kg of artesunate and thereafter 15 mg/kg of mefloquine simultaneously (group A), after 8 hours (after group B), and after 24 hours (group C). Three dosages were completed with placebo. Follow-up was 28 days. All patients recovered rapidly except one case of failure within the first 24 hours. Mefloquine pharmacokinetics was similar in the three regimens. Parasites reappeared in 26%, 26%, and 33% of the patients in groups A, B, and C, respectively. Early recrudescence was associated with high initial parasite density, slow parasite clearance, and rapid mefloquine clearance and low plasma concentrations at day 28. Mefloquine plasma concentrations all reached therapeutic ranges, suggesting reduced parasite sensitivity. In conclusion, there is no interaction between artesunate and mefloquine with respect to tolerance, efficacy, and pharmacokinetics. Single-dose combination therapy with artemisinin drugs and 15 mg/kg of mefloquine does not completely prevent parasite recurrence and may not prevent mefloquine resistance.
Full-text · Article · Sep 2004 · The American journal of tropical medicine and hygiene
[Show abstract][Hide abstract] ABSTRACT: To study a new combination, based on dihydroartemisinin and piperaquine (CV8) and atovaquone/proguanil (Malarone) for treatment of uncomplicated falciparum malaria in Vietnam.
Vietnamese adults with falciparum malaria were allocated randomly to treatment with dihydroartemisinin/piperaquine/trimethoprim/primaquine 256/2560/720/40 mg (CV8, n = 84) or Malarone 3000/1200 mg (n = 81), both over 3 days. Patients were followed-up for 28 days.
All patients recovered rapidly. The mean (95% CI) parasite elimination half-life of CV8 was 6.8 h (6.2-7.4) and of Malarone 6.5 h (6.1-6.9) (P = 0.4). Complete parasite clearance time was 35 (31-39) and 34 h (31-38) (P = 0.9). The 28-day cure rate was 94% and 95%, respectively (odds ratio 0.84, 95% CI 0.18-3.81). No significant side-effects were found.
CV8 and Malarone are effective combinations against multi-drug resistant falciparum malaria. CV8 has the advantage of a low price.
Full-text · Article · Mar 2004 · Tropical Medicine & International Health
[Show abstract][Hide abstract] ABSTRACT: Malarone, a fixed combination of atovaquone with proguanil (AP), has recently been recognized as a promising treatment against multidrug-resistant Plasmodium falciparum. In Vietnam, the first-line treatment for P. falciparum malaria is currently a combination of mefloquine and an artemisinin derivative, and the use of AP has not been explored. The aim of the present study, based in Vietnam, was to assess the efficacy of AP when used to treat P. falciparum recrudescences that had occurred after primary treatment with mefloquine-artesunate. All but two of the 39 patients investigated completed follow-up. The mean parasite- and fever-clearance times [and 95% confidence intervals (CI)] after AP treatment were 36 (30-42) and 21 (18-24) h, respectively. Most (32) of the 37 infections that were followed adequately appeared to be eradicated by the AP, the other five recrudescing once more. The overall cure 'rate' and (CI) was 86% (76%-98%). All of the patients tolerated the AP well. Atovaquone-proguanil appears to be a safe and promising alternative treatment for P. falciparum infections in South-east Asia, although the combination is relatively expensive and may not clear some infections with multidrug-resistant parasites.
No preview · Article · Oct 2003 · Pathogens and Global Health
[Show abstract][Hide abstract] ABSTRACT: To follow malaria prospectively in an ethnic minority commune in the south of Viet Nam with high malaria transmission and seasonal fluctuation, during malaria control interventions using insecticide-treated bednets (ITBNs) and early diagnosis and treatment (EDT) of symptomatic patients.
From 1994 onwards the following interventions were used: distribution of ITBNs to all households with biannual reimpregnation; construction of a health post and appointment of staff trained in microscopic diagnosis and treatment of malaria; regular supply of materials and drugs; annual cross-sectional malaria surveys with treatment of all parasitaemic subjects, and a programme of community involvement and health education. Surveys were held yearly at the end of the rainy season. During the surveys, demographic data were updated. Diagnosis and treatment of malaria were free of charge. Plasmodium falciparum infection was treated with artesunate and P. vivax infection with chloroquine plus primaquine.
The baseline survey in 1994 recorded 716 inhabitants. Of the children under 2 years of age, 37% were parasitaemic; 56% of children aged 2-10 years, and 35% of the remaining population were parasitaemic. P. falciparum accounted for 73-79% of these infections. The respective splenomegaly rates for the above-mentioned age groups were 20%, 56%, and 32%. In 1999, the proportion of parasitaemic subjects was 4%, 7% and 1%, respectively, of which P.falciparum contributed 56%. The splenomegaly rate was 0%, 5% and 2%, respectively.
A combination of ITBNs and EDT, provided free of charge, complemented by annual diagnosis and treatment during malaria surveys and community involvement with health education successfully brought malaria under control. This approach could be applied to other regions in the south of Viet Nam and provides a sound basis for further studies in other areas with different epidemiological patterns of malaria.
Full-text · Article · Feb 2002 · Bulletin of the World Health Organisation
[Show abstract][Hide abstract] ABSTRACT: To investigate pituitary-adrenal function in acute uncomplicated falciparum malaria, we performed an overnight dexamethasone suppression test in 13 Vietnamese adults with acute malaria and 6 healthy controls. After blood samples were taken for serum cortisol and plasma ACTH at 23.00 hours on the admission day, 1 mg dexamethasone was given and further samples were taken at 08.00, 16.00 and 23.00 hours the next day. The patients received conventional antimalarial and supportive treatment. Baseline plasma ACTH concentrations in the patients [3.9 (0.2-41.2) pmol/l] and controls [3.4 (1.1-4.3) pmol/l] were similar (p=0.51), and exhibited a similar fall after dexamethasone to 0.6 (0.2-2.5) and 0.9 (0.7-1.6) pmol/l at 08.00 hours respectively (p<0.03 vs 23.00 hour values). Serum cortisol levels before dexamethasone were higher in the patients than in the controls [456 (102-821) vs 145 (64-183) nmol/l respectively; p=0.007] and the overnight fall was less in the patients [208 (26-340) and 23 (15-46) nmol/l at 08.00 hours respectively; p<0.001 vs 23.00 hour values and between groups]. Between 08.00 and 23.00 hours, plasma ACTH and serum cortisol remained suppressed in the controls. In the patients, the serum cortisol continued to fall progressively towards control values. These data suggest that there is a raised set point for cortisol inhibition of ACTH secretion but normal corticotrophin responsiveness to dexamethasone in uncomplicated malaria. A raised serum cortisol after dexamethasone in the patients might reflect the combination of a prolonged cortisol half-life and the stimulatory effects of cytokines on the adrenal cortex, with a consequent protective effect against complications such as hypoglycemia.
Full-text · Article · Dec 2001 · The Southeast Asian journal of tropical medicine and public health