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1.
《Acta tropica》2013,125(1):23-31
Quantitative real-time PCR (qPCR) is an accurate method to quantify Trypanosoma cruzi DNA and can be used to follow-up parasitemia in Chagas disease (CD) patients undergoing chemotherapy. The Benznidazole Evaluation for Interrupting Trypanosomiasis (BENEFIT) study is an international, multicenter, randomized, double-blinded and placebo-controlled clinical trial to evaluate the efficacy of benznidazole (BZ) treatment in patients with chronic Chagas cardiomyopathy (CCC). One important question to be addressed concerns the effectiveness of BZ in reducing overall parasite load in CCC patients, even in the absence of parasitological cure. This report describes the evaluation of multiple procedures for DNA extraction and qPCR-based protocols aiming to establish a standardized methodology for the absolute quantification of T. cruzi DNA in Guanidine-EDTA blood (GEB) samples. A panel of five primer sets directed to the T. cruzi nuclear satellite DNA repeats (Sat-DNA) and to the minicircle DNA conserved regions (kDNA) was compared in either SYBR Green or TaqMan systems. Standard curve parameters such as, amplification efficiency, coefficient of determination and intercept were evaluated, as well as different procedures to generate standard samples containing pre-established T. cruzi DNA concentration. Initially, each primer set was assayed in a SYBR Green qPCR to estimate parasite load in GEB samples from chronic Chagas disease patients. The results achieved from Bayesian transmutability analysis elected the primer sets Cruzi1/Cruzi2 (p = 0.0031) and Diaz7/Diaz8 (p = 0.0023) coupled to the QIAamp DNA Kit extraction protocol (silica gel column), as the most suitable for monitoring parasitemia in these patients. Comparison between the parasite burden of 150 GEB samples of BENEFIT patients from Argentina, Brazil and Colombia, prior to drug/placebo administration, was performed using Cruzi1/Cruzi2 primers in a SYBR Green approach. The median parasitemia found in patients from Argentina and Colombia (1.93 and 2.31 parasite equivalents/mL, respectively) was around 20 times higher than the one estimated for the Brazilian patients (0.1 parasite equivalents/mL). This difference could be in part due to the complexity of T. cruzi genetic diversity, which is a factor possibly implicated in different clinical presentations of the disease and/or influencing parasitemia levels in infected individuals from different regions of Latin America. The results of SYBR Green qPCR assays herein presented prove this methodology to be more cost efficient than the alternative use of internal fluorogenic probes. In addition, its sensitivity and reproducibility are shown to be adequate to detect low parasitemia burden in patients with chronic Chagas disease.  相似文献   

2.
IntroductionThe sensitivity and specificity of diagnostic techniques for Chagas disease depend largely on the antigens and targets used and on the immune response and characteristics of the infection of the population where it is applied, hence the need for evaluation of the diagnostic techniques available in a given area. So, the objective of this work was to evaluate two commercial kits for the immunological and molecular diagnosis of Chagas disease in endemic areas of Venezuela.MethodsThe evaluated kits were: Chagas ELISA IgG + IgM® and Speed Oligo Chagas® (Vircell®, Granada, Spain). They were evaluated with 129 samples (35 from patients in the acute phase, 33 in the chronic phase, 31 from patients with other diseases, and 30 from healthy individuals). The results were compared with those obtained in the conventional ELISA and PCR-satellite DNA tests for Trypanosoma cruzi.ResultsWith Chagas ELISA IgG + IgM® a sensitivity of 94.1% and specificity of 93.4% were obtained, with Speed Oligo Chagas® a sensitivity of 92.6% and specificity of 100% were achieved, values similar to those showed by conventional ELISA and satDNA-PCR.ConclusionThe sensitivity and specificity of the commercial kits evaluated make them suitable for the diagnosis of Chagas disease in endemic areas of Venezuela.  相似文献   

3.
《Acta tropica》2013,126(3):211-217
Domestic dogs and cats are major domestic reservoir hosts of Trypanosoma cruzi and a risk factor for parasite transmission. In this study we assessed the relative performance of a polymerase chain reaction assay targeted to minicircle DNA (kDNA-PCR) in reference to conventional serological tests, a rapid dipstick test and xenodiagnosis to detect T. cruzi infection in dogs and cats from an endemic rural area in northeastern Argentina. A total of 43 dogs and 13 cats seropositive for T. cruzi by an immunosorbent assay (ELISA) and an indirect hemagglutination assay (IHA), which had been examined by xenodiagnosis, were also tested by kDNA-PCR. kDNA-PCR was nearly as sensitive as xenodiagnosis for detecting T. cruzi-infectious dogs and cats. kDNA-PCR was slightly more sensitive than xenodiagnosis in seropositive dogs (91% versus 86%, respectively) and cats (77% against 54%, respectively), but failed to detect all of the seropositive individuals. ELISA and IHA detected all xenodiagnosis-positive dogs and both outcomes largely agreed (kappa coefficient, κ = 0.92), whereas both assays failed to detect all of the xenodiagnosis-positive cats and their agreement was moderate (κ = 0.68). In dogs, the sensitivity of the dipstick test was 95% and agreed closely with the outcome of conventional serological tests (κ = 0.82). The high sensitivity of kDNA-PCR to detect T. cruzi infections in naturally infected dogs and cats supports its application as a diagnostic tool complementary to serology and may replace the use of xenodiagnosis or hemoculture.  相似文献   

4.
A cross-sectional study was carried out in Água Comprida, MG, Brazil, a region previously endemic to Chagas disease whose vectorial transmission was interrupted around 20 year ago. A total of 998 individuals were examined for anti-Trypanosoma cruzi antibodies. Seropositivity was observed in 255 subjects (25.5%), and 743 subjects were negative. Forty-one families with 5–80 individuals with similar environmental conditions were selected for familial analysis. In 15 families, seropositivity to T. cruzi was observed in > 50% of individuals. The segregation analysis confirmed family aggregation for the seropositivity to the T. cruzi. Heart commitment was the major clinical form observed, and in six families, > 50% of the individuals display cardiopathy that may be attributed to T. cruzi infection. Our results support the hypothesis that there is a family aggregation for the seropositivity but without the effect of one major gene.  相似文献   

5.
ObjectiveTo verify the incidence of T. cruzi transmission through breastfeeding during acute experimental Chagas’ disease.MethodsFifteen female Swiss mice were mated and, after pregnancy confirmation, placed in individual cages. A few hours after birth, the females were inoculated with 0.1 mL of blood containing approximately 3 × 105 trypomastigote forms of Y strain of T. cruzi and continued breastfeeding for 25 days.ResultsIn 142 offspring examined no infection through breastfeeding was observed.ConclusionsThe low number of trypomastigote forms ingested by the newborn mice combined with biological and biochemical characteristics of blood trypomastigotes may explain the lack of transmission in this experiment.  相似文献   

6.
《Acta tropica》2013,127(1):6-13
ObjectivesTo evaluate the effect of benznidazole on endothelial activation in a murine model of Chagas disease.MethodsA low (30 mg/kg/day) and a high (100 mg/kg/day) dose of benznidazole were administered to mice infected with Trypanosoma cruzi during the early phases of the infection. The effects of the treatments were assessed at 24 and 90 days postinfection by evaluating the parasitaemia, mortality, histopathological changes and expression of ICAM in the cardiac tissue. The blood levels of thromboxane A2, soluble ICAM and E-selectin were also measured. T. cruzi clearance was assessed by the detection of parasite DNA in the heart tissue of infected mice.ResultsBenznidazole decreased the cardiac damage induced by the parasite, and amastigote nests disappeared at 90 days postinfection. Both doses cleared the parasite from the cardiac tissue at 24 and 90 days postinfection. In addition, benznidazole decreased the thromboxane levels and normalized the plasma sICAM and sE-selectin levels by 90 days postinfection.ConclusionsEarly administration of benznidazole at a dose as low as 30 mg/kg eradicates T. cruzi from cardiac tissue. Additionally, benznidazole prevents cardiac damage and modulates endothelial activation as part of its antichagasic activity.  相似文献   

7.
ObjectivesOur goal was to determine the prevalence of Trichomonas vaginalis and its associated factors among women living with HIV attending an AIDS clinic in Manaus, Amazonas, Brazil.MethodsCross-sectional study among women attending an AIDS clinic in Manaus between March and December 2010 for gynecological examination were invited to participate. Enrolled patients answered a face-to-face interview including demographic, behavioral and clinical data. They also underwent a gynecological evaluation and cervical scrape samples were collected for wet mount, Gram stain, culture and cytological analysis. A blood sample was obtained to determine TCD4+ lymphocytes and viral load.ResultsA total of 341 (91.2%) women participated in the study. The prevalence of T. vaginalis was 4.1% (95% CI: 2.0–6.2%). Median age was 32 (interquartile range 27–38) years and median years of schooling was 9.0 (interquartile range 4–11). A total of 165 (53.2%) HIV women were classified as patients with AIDS. In multivariate analyses, squamous intraepithelial lesions in cytology [OR = 2.46 (95% CI: 1.31–4.63, p = 0.005)] and anal sex practice [OR = 3.62 (95% CI: 1.08–12.19, p = 0.037)] were associated with T. vaginalis.ConclusionsThese results highlight that HIV-infected women should be screened for T. vaginalis. The control of this infection may have an impact on preventing reproductive complications among these women.  相似文献   

8.
The introduction of highly active antiretroviral therapy during the 1990s was crucial to the decline in the rates of morbidity and death related to the acquired immunodeficiency syndrome (AIDS) and turned human immunodeficiency virus (HIV) infection into a chronic condition. Consequently, the HIV/AIDS population is becoming older. The aim of this study was to describe the immunological, clinical and comorbidity profile of an urban cohort of patients with HIV/AIDS followed up at Instituto de Pesquisa Clinica Evandro Chagas, Oswaldo Cruz Foundation in Rio de Janeiro, Brazil. Retrospective data from 2307 patients during January 1st, 2008 and December 31st, 2008 were collected. For continuous variables, Cuzick's non-parametric test was used. For categorical variables, the Cochran–Armitage non-parametric test for tendency was used. For all tests, the threshold for statistical significance was set at 5%. In 2008, 1023 (44.3%), 823 (35.7%), 352 (15.3%) and 109 (4.7%) were aged 18–39, 40–49, 50–59 and ≥60 years-old, respectively. Older and elderly patients (≥40 years) were more likely to have viral suppression than younger patients (18–39 years) (p < 0.001). No significant difference in the latest CD4+ T lymphocyte count in the different age strata was observed, although elderly patients (≥ 50 years) had lower CD4+ T lymphocyte nadir (p < 0.02). The number of comorbidities increased with age and the same pattern was observed for the majority of the comorbidities, including diabetes mellitus, dyslipidemia, hypertension, cardiovascular diseases, erectile dysfunction, HCV, renal dysfunction and also for non-AIDS-related cancers (p < 0.001). With the survival increase associated to successful antiretroviral therapy and with the increasing new infections among elderly group, the burden associated to the diagnosis and treatment of the non-AIDS related HIV comorbidities will grow. Longitudinal studies on the impact of aging on the HIV/AIDS population are still necessary, especially in resource-limited countries.  相似文献   

9.
IntroductionA population-based survey conducted in Brazilian capital cities found that only 16% of the population had ever been tested for hepatitis C. These data suggest that much of the Brazilian population with HCV infection remains undiagnosed. The distribution of age ranges at diagnosis and its association with the degree of hepatitis C are still unknown in Brazilian patients.Material and methodsPatients with HCV infection, diagnosed by HCV RNA (Amplicor-HCV, Roche), were included in the study. Patients with HBV or HIV coinfection, autoimmune diseases, or alcohol intake > 20 g/day were excluded. HCV genotyping was performed by sequence analysis, and viral load by quantitative RT-PCR (Amplicor, Roche). The METAVIR classification was used to assess structural liver injury. The Chi-square (χ2) test and student's t-test were used for between-group comparisons. Spearman's rank correlation coefficient were used for analysing the correlation between parameters.ResultsA total of 525 charts were reviewed. Of the patients included, 49.5% were male, only 10% of the patients were aged less than 30 years; peak prevalence of HCV infection occurred in the 51-to-60 years age range. Genotype 1 accounted for 65.4% of the cases. Information on HCV subtype was obtained in 227 patients; 105 had subtype 1a and 122 had 1b. According to the degree of structural liver injury, 8.3% had F0, 23.4% F1, 19.8% F2, 11.9% F3, and 36.5% F4. Age at diagnosis of hepatitis correlated significantly with fibrosis (rs = 0.307, p < 0.001). The degree of fibrosis increased with advancing age. Only age at diagnosis and fasting blood glucose were independently associated with disease stage. Those patients with subtype 1a had higher prevalence of F2–F4 than those with subtype 1b.ConclusionIn Brazil, diagnosis of hepatitis C is more commonly established in older patients (age 45–60 years) with more advanced disease. Reassessment of strategies for hepatitis C diagnosis in the country is required.  相似文献   

10.
Co-infections of hepatitis C virus (HCV) and either human immunodeficiency virus type 1 (HIV-1), human T-cell lymphotropic virus type 1 (HTLV-1) or type 2 (HTLV-2) have been described as having an impact on HCV viremia and subsequent disease progression. HCV load in serum samples from 622 patients (343 males, 279 females; median age 50.8 years) from São Paulo/southeast Brazil was analyzed using the Abbott Real Time HCV assay (Abbott Molecular Inc., IL, USA). Samples were obtained from HCV-monoinfected (n = 548), HCV/HIV-1- (n = 41), HCV/HTLV-1- (n = 16), HCV/HTLV-2- (n = 8), HCV/HIV/HTLV-1- (n = 4), and HCV/HIV/HTLV-2-co-infected (n = 5) patients, and results were compared among the groups and according to sex. The median HCV load in HCV-monoinfected patients was 5.23 log10 IU/mL and 0.31 log10 higher in men than in women. Increases in viral load of 0.51 log10, 0.54 log10, and 1.43 log10 IU/mL were detected in HCV/HIV-1-, HCV/HTLV-1- and HCV/HIV/HTLV-1-co-infected individuals, respectively, compared with HCV-monoinfected counterparts. In contrast, compared to HCV/HIV co-infected patients, HCV/HTLV-2-co-infected patients had an HCV load of 5.0 log10 IU/mL, whereas HCV/HIV/HTLV-2-co-infected patients had a median load 0.37 log10 IU/mL lower. Significant differences in HCV loads were detected, with males and HCV/HIV-1- and HCV/HIV/HTLV-1-co-infected patients presenting the highest values. Conversely, females and HCV/HTLV-2-co-infected patients exhibited lower HCV loads. Overall, HCV viremia is increased in HIV and/or HTLV-1-co-infection and decreased in HTLV-2 co-infection.  相似文献   

11.
Fogo Selvagem (FS) is an autoimmune bullous disease with pathogenic IgG autoantibodies recognizing desmoglein 1 (Dsg1), a desmosomal glycoprotein. In certain settlements of Brazil, a high prevalence of FS (3%) is reported, suggesting environmental factors as triggers of the autoimmune response. Healthy individuals from endemic areas recognize nonpathogenic epitopes of Dsg1, and exposure to hematophagous insects is a risk factor for FS. Fogo selvagem and Chagas disease share some geographic sites, and anti-Dsg1 has been detected in Chagas patients. Indeterminate Chagas disease was identified in a Brazilian Amerindian population of high risk for FS. In counterpart, none of the FS patients living in the same geographic region showed reactivity against Trypanosoma cruzi. The profile of anti-Dsg1 antibodies showed positive results in 15 of 40 FS sera and in 33 of 150 sera from healthy individuals from endemic FS sites, and no cross-reactivity between Chagas disease and FS was observed.  相似文献   

12.
We standardized serodiagnosis of dogs infected with Trypanosoma cruzi using TESA (trypomastigote excreted-secreted antigen)-blot developed for human Chagas disease. TESA-blot showed 100% sensitivity and specificity. In contrast, ELISA using TESA (TESA-ELISA) or epimastigotes (epi-ELISA) as antigen yielded 100% sensitivity but specificity of 94.1% and 49.4%, respectively. When used in field studies in an endemic region for Chagas disease, visceral leishmaniasis and Trypanosoma evansi (Mato Grosso do Sul state, Central Brazil), positivities were 9.3% for TESA-blot, 10.7% for TESA-ELISA and 32% for epi-ELISA. Dogs from a non-endemic region for these infections (Rondonia state, western Amazonia) where T. cruzi is enzootic showed positivity of 4.5% for TESA-blot and epi-ELISA and 6.8% for TESA-ELISA. Sera from urban dogs from Santos, São Paulo, where these diseases are absent, yielded negative results. TESA-blot was the only method that distinguished dogs infected with T. cruzi from those infected with Leishmania chagasi and/or Trypanosoma evansi.  相似文献   

13.
The objective of the study is to investigate the prevalence of malaria and HIV coinfection and assess the effect of HIV coinfection on malaria disease severity in malaria patients from the endemic area of Thailand along the Thai–Myanmar border. Blood samples were collected from a total of 867 patients with malaria (all species and severity) who attended Mae Tao clinic for migrant workers, Tak Province during 2005–2007 (439 samples), 2008–2010 (273 samples), and 2011–2013 (155 samples). The average prevalence rate of malaria and HIV coinfected cases in this malaria endemic area of the country during the three periods was 1.85%. HIV coinfection was observed only in samples with mono-infection of Plasmodium falciparum or Plasmodium vivax, with similar proportions (0.81 vs. 1.04%). Patients’ admission parasite density, an indicator of disease severity, was significantly higher in cases with HIV coinfection observed during 2008–2010. Anemia was found at a significantly higher frequency in patients coinfected with malaria and HIV observed during 2005–2007 compared with those infected with malaria alone. No association was observed between malaria and HIV coinfection and gender, and infected malaria species during the three observation periods. Patients with malaria and HIV coinfection had a significantly lower hemoglobin level than those with malaria infection alone. In conclusion, the prevalence of malaria and HIV coinfection in population of the malaria endemic area along the Thai–Myanmar border is low. HIV coinfection tended to increase parasite density, an indicator of malaria disease severity.  相似文献   

14.
15.
The elimination of domestic triatomines is the foundation of Chagas disease control. Regional initiatives are eliminating introduced triatomine species. In this scenario, endemic triatomines can occupy the ecological niches left open and become a threat to long-term Chagas disease control efforts. This study determined the abundance, colonization, and Trypanosoma cruzi infection rate of the endemic Panstrongylus howardi in 10 rural communities located in Ecuador''s Manabí Province. In total, 518 individuals of P. howardi were collected. Infestation indices of 1.4% and 6.6% were found in the domestic and peridomestic environments, respectively. We determined a T. cruzi infection rate of 53.2% (N = 47) in this species. P. howardi has a high capacity to adapt to different habitats, especially in the peridomicile. This implies a considerable risk of transmission because of the frequency of intradomicile invasion. Therefore, this species needs to be taken into account in Chagas control and surveillance efforts in the region.  相似文献   

16.
17.
Our goal was to determine the prevalence of Trichomonas vaginalis and its associated risk factors in parturient women aged 15–24 years attending Brazilian public maternity units. Participants answered a demographic, behavioral, and clinical data questionnaire. A sample of urine was screened for T. vaginalis. A total 299 women participated in this study. The prevalence rate of T. vaginalis was 7.7% (95% CI: 4.7–10.7%). The factors associated with T. vaginalis were use of illicit drugs [OR = 4.70 (95% CI: 1.63–13.56, p = 0.004)] and not attending antenatal care [OR = 5.15 (95% CI: 1.15–23.25, p = 0.032)]. These data demonstrate that it is important to discuss how to include routine screening for T. vaginalis during antenatal care in Brazil.  相似文献   

18.
AimsTo determine the prevalence of metabolic syndrome (MS) and insulin resistance (IR) and their determinants in HIV on ART, ART naive HIV and HIV negative patients.MethodsCross sectional study. ART experienced HIV, ART naive HIV and HIV negative patients were compared for differences in prevalence of MS and IR. Determinants of MS and IR were assessed.ResultsPrevalence of MS by NCEP criteria was 26.6%, 15.7% and 21.9% (P = 0.3) respectively for HIV on ART, ART naive HIV and HIV negative groups. The MS rates with the IDF definition were 22.7%, 23.2% and 19.3% (P = 0.8) for HIV on ART, ART naive HIV and HIV negative patients respectively. Increased waist circumference by IDF criteria (P = 0.03), visceral to subcutaneous fat ratio (P = 0.049), hypertriglyceredemia (P < 0.001) and high LDL-Cholesterol (P < 0.001) were more common in HIV patients on ART than other groups. IR was found in 12.8%, 3.6% and 2.4% (P = 0.003) of HIV on ART, ART naive HIV and HIV negative groups respectively. Male gender (odds ratio (OR) 11 95% CI 3–48; P < 0.001) was independently associated with MS. HIV patients on ART (OR 6.6 95% CI 1.3–32.3; P = 0.020), IDF definition of MS (OR 3.4 95% CI 1.1–10.7; P = 0.040), NCEP definition of MS (OR 3.2 95% CI 1.01–10.3; P = 0.049) and low HDL-Cholesterol (OR 5.7 95% CI 1.2–27; P = 0.029) were independently associated with IR.ConclusionPrevalence of MS with IDF and NCEP definitions was similar across groups. HIV patients on ART and MS were independently associated with IR while male gender was independently associated with MS.  相似文献   

19.
To investigate the association of leprosy with hepatitis B virus (HBV) infection, as yet unknown for South Brazil, we assessed hepatitis B virus coinfection in 199 South Brazilian leprosy patients (119 lepromatous, 15 tuberculoid, 30 borderline, 12 undetermined and 23 unspecified) and in 681 matched blood donors by screening for the hepatitis B virus markers HBSAg and anti-HBc, using ELISA. Positive samples were retested and anti-HBc+ only samples were tested for the hepatitis B surface antibody (anti-HBs). There was a strong association between leprosy and hepatitis B virus infection (OR = 9.8, 95% CI = 6.4–14.7; p = 0.004·E−30), as well as an association between HBV infection and lepromatous leprosy, compared to other forms (OR = 2.4, 95% CI = 1.2–4.8; p = 0.017). We also found that confinement due to leprosy was associated with hepatitis B virus infection (OR = 3.9, 95% CI = 2.1–7.4; p = 0.015·E−3). Leprosy patients are susceptible to develop hepatitis B virus infection, especially lepromatous. Institutionalized patients, who probably present a stronger Th2 response, have higher risk of being exposed to hepatitis B virus. This clearly emphasizes the need for special care to leprosy patients in preventing hepatitis B virus coinfection in South Brazil.  相似文献   

20.
Sexually transmitted diseases are still highly prevalent worldwide and represent an important public health problem. Psychiatric patients are at increased risk of sexually transmitted diseases but there are scarce published studies with representative data of this population. We sought to estimate the prevalence and correlates of self-reported sexually transmitted diseases among patients with mental illnesses under care in a national representative sample in Brazil (n = 2145). More than one quarter of the sample (25.8%) reported a lifetime history of sexually transmitted disease. Multivariate analyses showed that patients with a lifetime sexually transmitted disease history were older, had history of homelessness, used more alcohol and illicit drugs, suffered violence, perceived themselves to be at greater risk for HIV and had high risk sexual behavioral: practised unprotected sex, started sexual life earlier, had more than ten sexual partners, exchanged money and/or drugs for sex and had a partner that refused to use condom. Our findings indicate a high prevalence of self-reported sexually transmitted diseases among psychiatric patients in Brazil, and emphasize the need for implementing sexually transmitted diseases prevention programs in psychiatric settings, including screening, treatment, and behavioral modification interventions.  相似文献   

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