Publications by authors named "Aluizio Prata"

63 Publications

High similarity of Trypanosoma cruzi kDNA genetic profiles detected by LSSP-PCR within family groups in an endemic area of Chagas disease in Brazil.

Rev Soc Bras Med Trop 2014 Sep-Oct;47(5):653-6

Disciplina de Parasitologia, Departamento de Ciências Biológicas, Universidade Federal do Triângulo Mineiro, Uberaba, MG, Brazil.

Introduction: Determining the genetic similarities among Trypanosoma cruzi populations isolated from different hosts and vectors is very important to clarify the epidemiology of Chagas disease.

Methods: An epidemiological study was conducted in a Brazilian endemic area for Chagas disease, including 76 chronic chagasic individuals (96.1% with an indeterminate form; 46.1% with positive hemoculture).

Results: T. cruzi I (TcI) was isolated from one child and TcII was found in the remaining (97.1%) subjects. Low-stringency single-specific-primer-polymerase chain reaction (LSSP-PCR) showed high heterogeneity among TcII populations (46% of shared bands); however, high similarities (80-100%) among pairs of mothers/children, siblings, or cousins were detected.

Conclusions: LSSP-PCR showed potential for identifying similar parasite populations among individuals with close kinship in epidemiological studies of Chagas disease.
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http://dx.doi.org/10.1590/0037-8682-0255-2013DOI Listing
July 2015

Length and caliber of the rectosigmoid colon among patients with Chagas disease and controls from areas at different altitudes.

Rev Soc Bras Med Trop 2013 Nov-Dec;46(6):746-51

Disciplina de Doenças Infecciosas e Parasitárias, Departamento de Clínica Médica, Faculdade de Medicina, Universidade Federal do Triângulo Mineiro, UberabaMG.

Introduction: In this study, we investigated radiological changes in the sigmoid colon in chagasic patients by comparing their colon lengths and caliber with those of non-chagasic living in the same region and non-chagasic living at high altitudes.

Methods: A total of 317 individuals were evaluated using clinical, serological and radiological methods and divided into three groups: 1) one hundred and nine non-chagasic individuals from Uberaba, Brazil; 2) sixty-one non-chagasic from Puno, Peru; 3) one hundred forty-seven chagasics examined in Uberaba, being 62 without megacolon (3A), 72 with megacolon (3B) and 13 with doubtful diagnosis of megacolon (3C).

Results: In group 2, the sigmoid colon had a significantly larger caliber (p=0.001) and the rectosigmoid colon was longer (p<0.001) than group 1. In subgroup 3A, the sigmoid colon (p<0.001) and rectum (p<0.001) had a significantly larger caliber and the rectosigmoid was longer (p<0.001) than that of the non-chagasic individuals. In subgroup 3B, the rectosigmoid was longer in all patients, and the caliber of the sigmoid was significantly larger than that of subjects in subgroups 3A and 3C (p<0.001).

Conclusions: Morphometric analysis confirms that Chagas disease may increase the caliber and length of the rectosigmoid. Our results suggest that altitude, ethnicity and diet may have influenced the size and length of the rectosigmoid of andean patients.
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http://dx.doi.org/10.1590/0037-8682-0247-2013DOI Listing
April 2014

Use of the polymerase chain reaction for the diagnosis of asymptomatic Leishmania infection in a visceral leishmaniasis-endemic area.

Rev Inst Med Trop Sao Paulo 2013 Mar-Apr;55(2):101-4

Universidade Federal do Triângulo Mineiro.

The diagnosis of asymptomatic infection with Leishmania (Leishmania) chagasi has become more important over recent years. Expansion of visceral leishmaniasis might be associated with other routes of transmission such as transfusion, congenital or even vector transmission, and subjects with asymptomatic infection are potential reservoirs. Moreover, the identification of infection may contribute to the management of patients with immunosuppressive conditions (HIV, transplants, use of immunomodulators) and to the assessment of the effectiveness of control measures. In this study, 149 subjects living in a visceral leishmaniasis endemic area were evaluated clinically and submitted to genus-specific polymerase chain reaction (PCR), serological testing, and the Montenegro skin test. Forty-nine (32.9%) of the subjects had a positive PCR result and none of them developed the disease within a follow-up period of three years. No association was observed between the results of PCR, serological and skin tests. A positive PCR result in subjects from the endemic area did not indicate a risk of progression to visceral leishmaniasis and was not associated with a positive result in the serological tests.
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http://dx.doi.org/10.1590/s0036-46652013000200006DOI Listing
September 2013

Occurrence of dolichocolon without megacolon in chronic Chagas disease patients.

Rev Soc Bras Med Trop 2012 Jun;45(3):353-6

Núcleo de Medicina Tropical, Universidade de Brasília, Brasília, DF, Brasil.

Introduction: Since 1970, lengthening of the rectosigmoid has been suspected to be a solitary manifestation of Chagas colopathy.

Methods: To test this hypothesis, opaque enema was administered on 210 seropositive and 63 seronegative patients, and radiographs in the anteroposterior and posteroanterior positions were examined blind to the serological and clinical findings. The distal colon was measured using a flexible ruler along the central axis of the image from the anus to the iliac crest.

Results: Dolichocolon was diagnosed in 31 (14.8%) seropositive and 3 (4.8%) seronegative patients. The mean length was 57.2 (±12.2)cm in seropositive patients and 52.1 (±8.8)cm in the seronegative patients (p = 0.000), that is, the distal colon in Chagas patients was, on average, 5.1cm longer. Seropositive female patients presented a mean length of 58.8 (±12.3)cm, and seronegative female patients presented 53.2 (±9.1)cm (p = 0.002). Seropositive male patients had a mean length of 55 (±11.6)cm, and seronegative male patients had 49.9 (±7.8)cm (p = 0.02). Among 191 patients without megacolon and suspected megacolon, the mean length was 56.3 (±11.6)cm in seropositive individuals and 52 (±8.8)cm in seronegative patients (p = 0.003). Among individuals with distal colon >70cm, there were 31 Chagas patients with mean length of 77.9 (±7.1)cm and three seronegative with 71.3 (±1.1)cm (p = 0.000). Among 179 with distal colon <70cm, seropositive individuals had a mean length of 53.6 (±8.8)cm, and seronegative patients had 51.2 (±7.8)cm (p = 0.059). Serological positive women had longer distal colon than men (p = 0.02), whereas the mean length were the same among seronegative individuals (p = 0.16).

Conclusions: In endemic areas of Brazil Central, solitary dolichocolon is a radiological Chagas disease signal.
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http://dx.doi.org/10.1590/s0037-86822012000300014DOI Listing
June 2012

Seroprevalence of Helicobacter pylori infection in chagasic and nonchagasic patients from the same geographical region of Brazil.

Rev Soc Bras Med Trop 2012 Mar-Apr;45(2):194-8

Departamento de Ciências Biológicas, Universidade Federal do Triângulo Mineiro, Uberaba, MG.

Introduction: In this study, we evaluated the seroprevalence of Helicobacter pylori infection among chagasic and non-chagasic subjects as well as among the subgroups of chagasic patients with the indeterminate, cardiac, digestive, and cardiodigestive clinical forms.

Methods: The evaluated subjects were from the Triângulo Mineiro region, Minas Gerais, Brazil. Chagasic patients showed positive reactions to the conventional serological tests used and were classified according to the clinical form of their disease. Immunoglobulin G antibodies specific to H. pylori were measured using a commercial enzyme-linked immunosorbent assay kit.

Results: The overall H. pylori prevalence was 77.1% (239/310) in chagasic and 69.1% (168/243) in non-chagasic patients. This difference was statistically significant even after adjustment for age and sex (odds ratio = 1.57; 95% confidence interval, 1.02-2.42; p = 0.04) in multivariate analysis. The prevalence of infection increased with age in the non-chagasic group (p = 0.007, χ² for trend), but not in the chagasic group (p = 0.15, χ² for trend). H. pylori infection was not associated with digestive or other clinical forms of Chagas disease (p = 0.27).

Conclusions: Our findings demonstrate that chagasic patients have a higher prevalence of H. pylori compared to non-chagasic subjects; a similar prevalence was found among the diverse clinical forms of the disease. The factors contributing to the frequent co-infection with H. pylori and Trypanosoma cruzi as well as its effects on the clinical outcome deserve further study.
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http://dx.doi.org/10.1590/s0037-86822012000200011DOI Listing
October 2012

Frequency of metabolic syndrome and the food intake patterns in adults living in a rural area of Brazil.

Rev Soc Bras Med Trop 2011 Jul-Aug;44(4):425-9

Disciplina de Nutrologia, Departamento de Clínica Médica, Universidade Federal do Triângulo Mineiro,Uberaba, MG, Brasil.

Introduction: Metabolic syndrome (MetS), a risk factor for atherosclerosis and coronary heart disease, is related to an inadequate food intake pattern. Its incidence is increasing among Brazilian adults, including those living in rural areas. Our aim was not only to describe the frequency of MetS in adults with or without MetS but also to compare their food intake pattern as assessed by the healthy eating index (HEI) and serum albumin and C reactive protein (CRP) levels.

Methods: Men and women (n = 246) living in a small village in Brazil were included. MetS was characterized according to the adult treatment panel (ATP III) criteria. Groups were compared by chi-square, student t or Mann-Whitney tests.

Results: MetS was diagnosed in 15.4% of the cases. The MetS group showed higher CRP (1.8±1.2 vs. 1.0±0.9 mg/dl) and lower albumin (4.3±0.3 vs. 4.4±0.3 g/dl) serum levels compared to the control group. Additionally, the MetS group showed lower scores (median[range]) in the HEI compared to the control group (53.5[31.2-78.1] vs 58[29.7-89.5], respectively). The MetS group also had decreased scores for total fat and daily variety of food intake.

Conclusions: The results suggest that adults with MetS displayed chronic mild inflammation and a poorer food intake pattern than the control group.
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http://dx.doi.org/10.1590/s0037-86822011000400005DOI Listing
February 2012

[The national survey of seroprevalence for evaluation of the control of Chagas disease in Brazil (2001-2008)].

Rev Soc Bras Med Trop 2011 ;44 Suppl 2:108-21

Laboratório de Doença de Chagas, Hospital das Clínicas, Universidade Federal de Goiás, Goiânia, GO, Brazil.

A survey for seroprevalence of Chagas disease was held in a representative sample of Brazilian individuals up to 5 years of age in all the rural areas of Brazil, with the single exception of Rio de Janeiro State. Blood on filter paper was collected from 104,954 children and screened in a single laboratory with two serological tests: indirect immunofluorescence and enzyme linked immunoassay. All samples with positive or indetermined results, as well as 10% of all the negative samples were submitted to a quality control reference laboratory, which performed both tests a second time, as well as the western blot assay of TESA (Trypomastigote Excreted Secreted Antigen). All children with confirmed final positive result (n = 104, prevalence = 0.1%) had a follow-up visit and were submitted to a second blood collection, this time a whole blood sample. In addition, blood samples from the respective mothers and familiar members were collected. The infection was confirmed in only 32 (0.03%) of those children. From them, 20 (0.025%) had maternal positive results, suggesting congenital transmission; 11 (0.01%) had non-infected mothers, indicating a possible vectorial transmission; and in one whose mother had died the transmission mechanism could not be elucidated. In further 41 visited children the infection was confirmed only in their mothers, suggesting passive transference of maternal antibodies; in other 18, both child and mother were negative; and in 13 cases both were not localized. The 11 children that acquired the infection presumably through the vector were distributed mainly in the Northeast region of Brazil (States of Piauí, Ceará, Rio Grande do Norte, Paraíba and Alagoas), in addition to one case in Amazonas (North region) and another in Parana (South region). Remarkably, 60% of the 20 cases of probably congenital transmission were from a single State, Rio Grande do Sul, with the remaining cases distributed in other states. This is the first report demonstrating regional geographical differences in the vertical transmission of Chagas disease in Brazil, which probably reflects the predominant Trypanosoma cruzi group IId and IIe (now TcV and TcVI) found in this state. Overall, these results show that the regular and systematic control programs against the transmission of Chagas disease, together with socioeconomic changes observed in Brazil in the last decades, interrupted the vectorial transmission in Brazil, resumed in the few cases found in this national survey. Furthermore they reinforce the need for maintenance of control programs for the consolidation of this major advance in public health.
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http://dx.doi.org/10.1590/s0037-86822011000800015DOI Listing
September 2011

[The electrocardiographic survey].

Rev Soc Bras Med Trop 2011 ;44 Suppl 2:40-6

Universidade Federal do Triângulo Mineiro, Uberaba, MG, Brazil.

In order to investigate the prevalence of chagasic heart disease in Brazil, a national electrocardiographic survey was carried out from 1977 to 1981. A total of 5,347 electrocardiograms (ECG) were performed and paired by age and gender. The results obtained in relation with the autochthonous cases, were distributed by Brazilian states, as follows: Rio Grande do Sul (1,078), Minas Gerais (760), Bahia (612), Paraná (400), Paraiba (340), Piauí (218), Sergipe (216), Goiás (176), Pernambuco (170), Ceará (136) and Alagoas 134. The higher proportions of altered ECGs among seropositive individuals were found in the States of Goiás (63.6%), Minas Gerais (57.6%), Ceará (57.3%), Paraná (54.5%), Piauí (53.2%) and Paraiba (52.3%). Among the control individuals, these proportions were respectively 25%, 25.7%, 25%, 12.5%, 22.9% and 26.5%. A significant statistical difference of altered ECGs between positive and negative individuals was verified in all the States, with a single exception (Alagoas). The estimation of the gradient showed to be higher in Paraná State (42%), followed by Goiás (38.6%), Ceará (32.3%), Minas Gerais (31.9%), Piauí (30.3%), Paraíba (25.8%), Pernambuco (22.3%), Bahia (18.9%), Sergipe (16.7%), Rio Grande do Sul (9.9%) and Alagoas (7.5%). Concerning the distribution of the electrocardiographical alterations found in the eleven states, the main alterations find among the seropositive group were: ventricular extrasystoles, complete right bundle branch block, left anterior fascicular block, the association of complete right bundle branch block with left anterior fascicular block and primary alterations of the ST segment and of the T wave. Furthermore, these ECG alterations were more prevalent in the group of infected individuals.
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http://dx.doi.org/10.1590/s0037-86822011000800007DOI Listing
September 2011

[Seroprevalence survey of human Chagas' infection (1975-1980)].

Rev Soc Bras Med Trop 2011 ;44 Suppl 2:33-9

Organização Panamericana de Saúde, Brasília, DF, Brazil.

The results of the Serological survey for the prevalence of chagasic infection in Brazil, 1975/1980, were published before (Camargo et al, 1984) but the detailed geographical distribution is described in this paper. This was an initiative of two governmental bodies: the Superintendencia de Campanhas de Saúde Pública a Ministry of Health Division in charge of all public health policies, and, the Research National Council of the Ministry of Science and Technology through a program called Integrated Program for Endemic Diseases. Results obtained were extremely useful for a precise delimitation of the area with endemic transmission of Chagas disease, and hence, to direct the activities for vector control, which were implemented from 1975 onwards. This survey showed an estimated seroprevalence of 4.2% of T. cruzi infection in the rural population in the country. Only two federal units were not included, São Paulo and the Federal District (Brasilia) for which enough recent information was available. This survey included all the other federal units of Brazil, with the examination of 1,626,745 blood samples by indirect immunofluorescence. From them, 1,352,197 were validated for processing and statistical analysis, which were from 3,026 municipalities of 24 states, as by the political division of the country by this time. Overall results obtained, confirmed data that were well known, but some were non expected. These last were subject of further investigations, until confirmation, based also on entomological data and a better interpretation of the results obtained.
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http://dx.doi.org/10.1590/s0037-86822011000800006DOI Listing
September 2011

[The beginning of the disease].

Rev Soc Bras Med Trop 2011 ;44 Suppl 2:6-11

Universidade Federal do Triângulo Mineiro, Uberaba, MG, Brazil.

Originating from the ancient enzootic cycle of Trypanosoma cruzi, human Chagas disease (HCD) emerged focally in different points of America, in the Pre Christian period. Being slowly expanded as a consequence of internal migrations, HCD was settled in those locals where some vector species reached domiciliation and where different kinds of reservoirs entered in domestic environment , with major expression in the post Columbus era, particularly between the final of XIX Century and the middle of XX Century, when the maximum prevalence rates were attained. Originally, scarce evidences of acute cases, chronic cardiopathy and megacolon could be detected in different points of the Region, but the diagnosis of such clinical pictures was not easily ascertained. Nevertheless, the megaoesophagus picture proved to be the more specific marker of ancient HCD, with several descriptions of its occurrence in different Brazilian regions, mainly since the XVIII Century. The social burden of HCD depends basically of the presence of chronic cardiopathy, and only after its recognition, control actions of the disease were definitely lounged in endemic countries.
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http://dx.doi.org/10.1590/s0037-86822011000800002DOI Listing
September 2011

Antileishmania immunological tests for asymptomatic subjects living in a visceral leishmaniasis-endemic area in Brazil.

Am J Trop Med Hyg 2011 Feb;84(2):261-6

Department of Tropical Medicine and Infectology, Federal University of Triângulo Mineiro, Uberaba, Brazil.

The objective of this study was to evaluate the behavior of different tests used for the diagnosis of visceral leishmaniasis (VL) in asymptomatic subjects living in an endemic area. No gold standard is available for the diagnosis of asymptomatic infection with Leishmania. In continuation of a previous study, 1,017 subjects living in a VL-endemic area were clinically reevaluated. Of these, 576 had at least one positive serological test in a first assessment. About 3 years after the first evaluation, none of the subjects had progressed to clinical VL. Among this group, 246 subjects were selected, and five serological tests (enzyme-linked immunosorbent assay p [ELISAp], ELISArK39, ELISArK26, indirect immunofluorescence test [IIFT] using L. amazonensis promastigote antigen, and an immunochromatographic test using rK39 antigen [TRALd]) and the Montenegro skin test (MST) were repeated. There was a significant increase in the number of subjects who tested positive in the MST, IIFT, ELISAp, and ELISArK39 in the second evaluation. For all tests, there were subjects who tested positive in the first evaluation and negative in the second evaluation. A positive result in the serological tests and MST in subjects from the endemic area studied did not indicate a risk of progression to VL and may only be temporary.
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http://dx.doi.org/10.4269/ajtmh.2011.10-0092DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3029179PMC
February 2011

[Radiological study on megacolon cases in an endemic area for Chagas disease].

Rev Soc Bras Med Trop 2010 Sep-Oct;43(5):562-6

Programa de Pós-Graduação em Medicina Tropical, Núcleo de Medicina Tropical, Universidade de Brasília, Brasília, DF.

Introduction: A radiological study on the colon of patients from an endemic Chagas disease zone was conducted using the simplified opaque enema technique of Ximenes et al.

Methods: The study involved 291 individuals with a mean age of 48.8 ± 12.5 years-old, of whom 222 were seropositive for Chagas disease. Anteroposterior, posteroanterior and left lateral view radiographs were analyzed by visual inspection and measurement of the largest rectal and sigmoid diameters.

Results: From the visual inspection, megacolon was diagnosed in 14 (6.3%) Chagas disease patients. The mean diameter of the rectal ampulla among the Chagas patients was 6.3 ± 1.0 cm, similar to the measurement in non-Chagas individuals: 6.2 ± 1.0 cm (p= 0.391). The mean sigmoid loop diameter in the Chagas patients was 5 ± 1.6 cm, which was larger than among the non-Chagas individuals: 4.4 ± 0.8 cm (p= 0.001).

Conclusions: excluding the evident and probable megacolon cases, the Chagas disease population continued to present a significantly larger mean sigmoid diameter than that observed among non-Chagas individuals (p= 0.003).
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http://dx.doi.org/10.1590/s0037-86822010000500018DOI Listing
April 2011

Serum hyaluronan and collagen IV as non-invasive markers of liver fibrosis in patients from an endemic area for schistosomiasis mansoni: a field-based study in Brazil.

Mem Inst Oswaldo Cruz 2010 Jul;105(4):471-8

Programa de Pós-Graduação em Ciências da Saúde, Infectologia e Medicina Tropical, Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil.

Non-invasive markers of fibrosis have been used to diagnose liver fibrosis in a variety of diseases. Hyaluronic acid (HA) and collagen IV (C-IV) levels were measured in the sera of patients from an endemic area for schistosomiasis in Brazil to diagnose and to rank the intensity of liver fibrosis. Seventy-nine adult patients with schistosomiasis, in the age range of 21-82 years (49 +/- 13.4) were submitted to clinical and ultrasonographic examinations. Ultrasound was employed to diagnose and categorise liver fibrosis according to World Health Organization patterns. Serum HA and C-IV levels were measured using commercial ELISA kits. Ultrasound revealed six patients with intense liver fibrosis, 21 with moderate, 23 with light and 29 without. Serum HA was able to separate individuals with fibrosis from those without (p < 0.001) and light from intense fibrosis (p = 0.029), but C-IV was not (p = 0.692). The HA diagnostic accuracy for fibrosis was 0.89. The 115.4 ng/mL cut-off level diagnosed patients with fibrosis (sensitivity 0.98, specificity 0.64). HA correlated positively with portal hypertension. Periportal fibrosis (subjective evaluation), age and collateral circulation predicted HA increase. In conclusion, we propose that serum HA can be used to identify patients with liver fibrosis in an endemic area for schistosomiasis mansoni in Brazil.
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http://dx.doi.org/10.1590/s0074-02762010000400020DOI Listing
July 2010

Comparison between clinical and ultrasonographic findings in cases of periportal fibrosis in an endemic area for schistosomiasis mansoni in Brazil.

Rev Soc Bras Med Trop 2010 Mar-Apr;43(2):129-34

University of Triângulo Mineiro, Uberaba, Minas Gerais, Brazil.

Introduction: Abdominal palpation and ultrasound findings among patients from an endemic area for schistosomiasis in Brazil who had been followed up for 27 years were compared.

Methods: In 2004, 411 patients from Brejo do Espírito Santo, in the State of Bahia, were selected for the present investigation after giving their written informed consent. Based on clinical data, they were divided into three groups: 41 patients with evidence of liver fibrosis in 2004 (Group 1); 102 patients with evidence of liver fibrosis in the past (1976-1989) but not in 2004 (Group 2); and 268 patients without evidence of liver fibrosis at any time during the 27-year follow-up (Group 3). All of the patients underwent abdominal ultrasound in which the examiner did not know the result from the clinical examination. The data were stored in a database.

Results: The prevalence of periportal fibrosis on ultrasound was 82.9%, 56.9% and 13.4% in Groups 1, 2 and 3, respectively. In the presence of hard, nodular liver or prominent left lobe and a hard palpable spleen, ultrasound revealed periportal fibrosis in 70.9%. However, periportal fibrosis was diagnosed using ultrasound in 25.4% of the patients in the absence of clinical evidence of liver involvement. Thus, ultrasound diagnosed periportal fibrosis 3.1 times more frequently than clinical examination did.

Conclusions: Although clinical examination is important in evaluating morbidity due to Manson's schistosomiasis in endemic areas, ultrasound is more accurate in diagnosing liver involvement and periportal fibrosis.
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http://dx.doi.org/10.1590/s0037-86822010000200005DOI Listing
August 2010

Familial analysis of seropositivity to Trypanosoma cruzi and of clinical forms of Chagas disease.

Am J Trop Med Hyg 2010 Jan;82(1):45-8

Disciplina de Genética, Federal University of the Triângulo Mineiro, Uberaba, Minas Gerais, Brazil.

A cross-sectional study was carried out in Agua 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.
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http://dx.doi.org/10.4269/ajtmh.2010.08-0626DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2803508PMC
January 2010

Variants of CTGF are associated with hepatic fibrosis in Chinese, Sudanese, and Brazilians infected with schistosomes.

J Exp Med 2009 Oct 12;206(11):2321-8. Epub 2009 Oct 12.

Institut National de la Santé et de la Recherche Médicale, U906, 13385 Marseille, France.

Abnormal fibrosis occurs during chronic hepatic inflammations and is the principal cause of death in hepatitis C virus and schistosome infections. Hepatic fibrosis (HF) may develop either slowly or rapidly in schistosome-infected subjects. This depends, in part, on a major genetic control exerted by genes of chromosome 6q23. A gene (connective tissue growth factor [CTGF]) is located in that region that encodes a strongly fibrogenic molecule. We show that the single nucleotide polymorphism (SNP) rs9402373 that lies close to CTGF is associated with severe HF (P = 2 x 10(-6); odds ratio [OR] = 2.01; confidence interval of OR [CI] = 1.51-2.7) in two Chinese samples, in Sudanese, and in Brazilians infected with either Schistosoma japonicum or S. mansoni. Furthermore, SNP rs12526196, also located close to CTGF, is independently associated with severe fibrosis (P = 6 x 10(-4); OR = 1.94; CI = 1.32-2.82) in the Chinese and Sudanese subjects. Both variants affect nuclear factor binding and may alter gene transcription or transcript stability. The identified variants may be valuable markers for the prediction of disease progression, and identify a critical step in the development of HF that could be a target for chemotherapy.
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http://dx.doi.org/10.1084/jem.20090383DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2768853PMC
October 2009

[Schistosoma-associated chronic septicemic salmonellosis: evolution of knowledge and immunopathogenic mechanisms].

Rev Soc Bras Med Trop 2009 Jul-Aug;42(4):436-45

Laboratório de Imunologia Celular, Patologia, Faculdade de Medicina, Universidade de Brasília, Brasília, DF.

Chronic septicemic salmonellosis is an individualized clinical entity characterized by prolonged fever with enlargement of the liver and spleen that occurs in Schistosoma-infected individuals who are coinfected with Salmonella. Several immunopathogenic mechanisms are involved, and they depend on the peculiarities of the interactions between Salmonella and various species of the genus Schistosoma. The modifications to the immune system that are caused by parasite infection are responsible for the evolution of the disease. In this review, we analyze the evolution of the knowledge on this entity and discuss the possible immuno-physiopathogenic mechanisms that contribute towards its development.
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http://dx.doi.org/10.1590/s0037-86822009000400015DOI Listing
March 2010

Comparative study of serologic tests for the diagnosis of asymptomatic visceral leishmaniasis in an endemic area.

Am J Trop Med Hyg 2009 Jul;81(1):27-33

Department of Tropical Medicine and Infectology, Federal University of Triângulo Mineiro, Uberaba, MG, Brazil.

Serologic tests have been widely used for the diagnosis of asymptomatic visceral leishmaniasis. This study evaluated five serologic tests used for the diagnosis of asymptomatic infection: enzyme-linked immunosorbent assay (ELISA) using promastigote antigen (ELISAp), ELISA using recombinant K39 (ELISA rK39), and K26 (ELISA rK26) antigens, an indirect immunofluorescence test using Leishmania (Leishmania) amazonensis promastigote antigen (IIFT), and an immunochromatographic test using rK39 antigen (TRALd). As a reference regarding the performance of the tests, patients with classic visceral leishmaniasis originating from Minas Gerais, Brazil (N = 36), were defined as the positive group and samples of healthy individuals from nonendemic areas (Argentina) (N = 127) were used as negative controls. Patients with other diseases such as cutaneous leishmaniasis (N = 53) and malaria (N = 56) were also studied to evaluate the chance of cross-reactivity in these tests. Finally, subjects from an area endemic for visceral leishmaniasis in Brazil (Porteirinha, northern Minas Gerais) (N = 1241) were screened for asymptomatic infection with Leishmania and Chagas disease. The sensitivity of the serologic tests was 50% (18/36), 66.7% (24/36), 69.4% (25/36), 83.3% (30/36), and 88.9% (32/36) for ELISAp, ELISA rK26, ELISA rK39, IIFT, and TRALd, respectively. Specificity, calculated using the truly negative group, was 96% (122/127) for TRALd, 97.6% (124/127) for ELISAp and IIFT, and 100% (127/127) for ELISA rK39 and rK26. Positivity in at least one test employing recombinant antigen was observed in 24 (45%) patients with cutaneous leishmaniasis and 47 (82.4%) with malaria. In the visceral leishmaniasis-endemic area, the positivity of the serologic tests ranged from 3.9% to 37.5%. The enzyme-linked immunosorbent assay (ELISA) tests using recombinant antigens were more frequently positive in subjects with a history of exposure to human or canine visceral leishmaniasis (ELISArK39: 14.6% [149/1017] versus 37.5% [84/224]; ELISA rK26: 12.7% [129/1017] versus 21.4% [48/224], P < 0.001 for both). Kappa agreement was low, with a maximum value of 0.449 between ELISAp and IIFT. In addition, among the 112 IIFT-positive subjects, 75 (67%) also presented positive serology for Chagas disease. In conclusion, IIFT and TRALd presented the best performance to diagnose classic cases of visceral leishmaniasis in an endemic area. Cross-reactivity of the tests with Chagas disease, cutaneous leishmaniasis, and malaria should be taken into account. However, the differences in the positivity of the tests used, together with the low agreement between results, do not permit to select the best test for the diagnosis of asymptomatic Leishmania infection.
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July 2009

Th1/Th2 immune responses are associated with active cutaneous leishmaniasis and clinical cure is associated with strong interferon-gamma production.

Hum Immunol 2009 Jun 20;70(6):383-90. Epub 2009 Jan 20.

Laboratory of Immunology, Universidade Federal do Triângulo Mineiro, Minas Gerais, Brazil.

In leishmaniasis, Th1-related cytokines production seems to be crucial for host control of parasite burden and clinical cure. Visceral and diffuse cutaneous leishmaniasis are characterized by negative skin test for parasite antigens and failure to produce Th1 cytokines, whereas tegumentary leishmaniasis is characterized by positive skin test and the ability of peripheral blood mononuclear cells (PBMCs) to produce Th1 cytokines. In this study, specific antibody plasma levels and cytokine production in PBMC culture supernatants were evaluated by enzyme-linked immunoabsorbent assay in patients with active or cured cutaneous leishmanial lesions and in subjects without disease history living in the same endemic area. Higher tumor necrosis factor-alpha, interferon (IFN)-gamma, interleukin (IL)-12, IL-4, and IL-10 levels were observed in patients with active lesions, whereas cured subjects produced only IFN-gamma at elevated levels. Analysis of specific antibody isotypes correlate with cellular immune response observed in vitro, as the production of IgG1 and IgG3 was higher in patients with active lesions. Our results suggest the presence of a mixed Th1/Th2 response during active disease and that clinical cure is associated with a sustained Th1 response characterized by elevated IFN-gamma levels and down-modulation of IL-4 and IL-10 production.
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http://dx.doi.org/10.1016/j.humimm.2009.01.007DOI Listing
June 2009

Experimental infection of murine and human macrophages with Cystoisospora belli.

Acta Trop 2009 Aug 7;111(2):177-80. Epub 2009 May 7.

Departamento de Ciências Biológicas, Disciplina de Parasitologia, Universidade Federal do Triângulo Mineiro, Rua Frei Paulino, 30, Abadia, CEP 38025-180, Uberaba, Minas Gerais, Brazil.

Extraintestinal cystoisosporosis by Cystoisospora belli has already been reported in HIV/AIDS patients, generally involving preferential invasion of mesenteric and trachaeobronchial lymph nodes, liver and spleen by unizoic cysts of this parasite, which may infect macrophages. To test this hypothesis, murine and human macrophages were exposed to sporozoites of C. belli and cultures were observed daily after contact with these cells. The parasites penetrated and multiplied by endodyogeny in both cell types and inserted themselves inside perinuclear vacuoles. After 48 h, extracellular parasites were removed from macrophage cultures and incubated in Monkey Kidney Rhesus cells (MK2) where there was intense multiplication. This is the first report of infection of macrophages by this parasite, which supports the hypothesis that these could act as C. belli host cells in extraintestinal sites.
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http://dx.doi.org/10.1016/j.actatropica.2009.04.010DOI Listing
August 2009

Mortality indicators among chronic Chagas patients living in an endemic area.

Int J Cardiol 2010 Sep 31;143(3):235-42. Epub 2009 Mar 31.

Cardiology Division, Department of Internal Medicine, Federal University of the Triângulo Mineiro, Brazil.

Background: Chagas disease is a serious social-medical problem in Latin American countries because of its high incidence, morbidity and mortality. Our aim was to identify, from demographic, personal history, clinical and electrocardiographic variables, those that might have independent prognostic value regarding mortality, among a population of chronic Chagas patients from a single endemic area where vector transmission has been halted.

Methods And Results: Over a mean of 18.5 years, we followed up a prospective cohort of 120 individuals with chronic Chagas disease. Twenty dichotomous variables with prognostic potential for chronic Chagas disease patients were initially evaluated using the Cox model (univariable analysis), to calculate the proportional mortality risk from all causes, cardiovascular causes and sudden death, relative to each variable separately. Of these, 12 variables presenting statistical significance (p<0.05) were included in a multivariable model to determine which of them would have independent prognostic value regarding mortality. Over the follow-up, there were 42 deaths. Eight variables were proven to be independent prognostic factors for mortality, in relation to the three types of death analysed: age ≥39 years, black skin colour, high-degree right-branch block, anterosuperior division block of the left branch, high-degree right-branch block associated with anterosuperior division block of the left branch, high-degree left-branch block, polymorphic ventricular extrasystoles and PR interval ≥0.16 s.

Conclusions: The presence on conventional electrocardiograms of polymorphic ventricular extrasystoles or high-degree left-branch block, among a population of chronic Chagas patients, constitutes the most important independent factor for poor prognosis.
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http://dx.doi.org/10.1016/j.ijcard.2009.02.011DOI Listing
September 2010

Virological and histological re-evaluation of Labrea hepatitis.

Acta Gastroenterol Latinoam 2008 Dec;38(4):284-90

Gastro-Hepatology Unit, Federal University of Bahia, Brazil.

Background: a peculiar form of fulminant hepatitis known as Labrea hepatitis, probably related to hepatitis B and D, has been reported in Brazilian Amazon as early as the 1930s.

Methods: we reviewed the postmortem liver biopsies of 9 patients with Labrea Hepatitis. Immunostaining for HBV and HDV antigens were performed.

Results: we found several important characteristics in the liver tissues: 1) moderate hepatocellular necro-inflammation, 2) hepatocellular ballooning, 3) ballooned hepatocytes with fat droplets surrounding the nucleus (morula-like cells or spongiocytes), 4) mild to moderate necrosis and/or mild portoseptal fibrosis. Hepatitis B surface antigen (HBsAg) was identified in 7 of the 9 cases and was concentrated in the Morula-like cells. Hepatitis B core antigen (HBcAg) was present in 5 cases, mostly in the hepatocyte's nucleous. The hepatitis D virus antigen (HDV Ag) was present in 5 cases, mostly in the cytoplasm and concentrated in the Morula-like cells.

Conclusion: labrea hepatitis is a fatal disease mostly affecting isolated communities in the Amazon. Evidence implicates HBV and HDV in the etiology of this disease, but this hypothesis needs to be confirmed with genotyping and sequencing research on HBV DNA and HDV RNA extracted from the liver and sera of these patients.
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December 2008

[The centenary of the discovery of Schistosoma mansoni in Brazil].

Authors:
Aluízio Prata

Rev Soc Bras Med Trop 2008 Nov-Dec;41(6):689-91

Universidade Federal do Triângulo Mineiro, Uberaba, MG, Brazil.

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http://dx.doi.org/10.1590/s0037-86822008000600027DOI Listing
May 2009

[Amadeu Cury (*1917 2008)].

Authors:
Aluízio Prata

Rev Soc Bras Med Trop 2008 Sep-Oct;41(5):545

Universidade Federal do Triângulo Mineiro.

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http://dx.doi.org/10.1590/s0037-86822008000500023DOI Listing
April 2009

Further evidence of spontaneous cure in human Chagas disease.

Rev Soc Bras Med Trop 2008 Sep-Oct;41(5):505-6

Fundação Oswaldo Cruz, Belo Horizonte, MG.

An acute case of Chagas disease was studied in 1944, with clinical and laboratory follow-up until 2007, in Bambuí, Minas Gerais, Brazil. A five-year-old girl living in a rural hut that was highly infested with Triatoma infestans presented a febrile clinical condition compatible with the acute form of trypanosomiasis. She presented a positive thick blood smear, but never again showed serological and/or parasitological evidence of Trypanosoma cruzi infection, on several occasions. This patient never received any specific treatment and, to this day, she remains completely asymptomatic, with normal findings from clinical, electrocardiographic, X-ray and echocardiographic examinations.
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http://dx.doi.org/10.1590/s0037-86822008000500014DOI Listing
April 2009

[Emmanuel Dias: the principal architect of the fight against Chagas disease in the Americas].

Rev Soc Bras Med Trop 2008 Sep-Oct;41(5):502-4

Centro de Pesquisa René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, MG.

In 2008, the centenary of the birth of Emmanuel Dias, whose life was intensely dedicated to the study, recognition and control of Chagas disease, is being celebrated. This summary of his life joins with the various homages paid in Brazil and abroad, to recall some of the key historical points in this scientist's career and the enormous social impact that resulted directly and indirectly from his work. Dias, who was Carlos Chagas' protégée and assistant, was considered by Chagas Filho to be the most proficient of his father's followers. Over the course of thirty years of activities, Dias began as a brilliant protozoologist and later on turned his attention towards facing the human disease. He worked intensively on diagnostics, epidemiology, clinical studies and control. He devised prospection strategies, mapped out the disease in the Americas, participated directly in systematizing chronic cardiopathy and described the first effective insecticide against triatomines, along with laying out the strategy for their control. Furthermore, he extended his activities throughout the field of this endemic disease: on the one hand, raising awareness about the disease and its control and, on the other hand, propelling health authorities and decision-making centers into action, to implement control measures. His work resulted in national and regional programs that have significantly reduced the transmission of the human disease throughout the continent. Dias was recently said to be the scientist who had had the all-time greatest impact on this trypanosomiasis.
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http://dx.doi.org/10.1590/s0037-86822008000500013DOI Listing
April 2009

Failure of both azithromycin and antimony to treat cutaneous leishmaniasis in Manaus, AM, Brazil.

Rev Inst Med Trop Sao Paulo 2008 May-Jun;50(3):157-60

Universidade Federal do Triângulo Mineiro, Uberaba, Minas Gerais, Brazil.

A non-randomized controlled clinical trial was carried out in order to evaluate both azithromycin and antimony efficacy in cutaneous leishmaniasis in Manaus, AM, Brazil. Forty nine patients from both genders, aged 14 to 70, with cutaneous ulcers for less than three months and a positive imprint for Leishmania spp. amastigotes were recruited into two groups. Group I (26 patients) received a daily-single oral dose of 500 mg of azithromycin for 20 days and Group II (23 patients) received a daily-single intramuscular dose of 20 mg/kg of meglumine antimony, also for 20 days. Azithromycin cured three of 24 (12.5%) patients on days 60, 90 and 120 respectively whereas therapeutic failure was considered in 21 of 24 (87.5%) cases. In group II, antimony cured eight of 19 (42.1%) cases as follows: three on day 30, one each on day 60 and day 90, and three on day 120. Therapeutic failure occurred in 11 of 19 (57.9%) individuals. The efficacy of antimony for leishmaniasis was better than azithromycin but analysis for the intention-to-treat response rate did not show statistical difference between them. Although azithromycin was better tolerated, it showed a very low efficacy to treat cutaneous leishmaniasis in Manaus.
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http://dx.doi.org/10.1590/s0036-46652008000300005DOI Listing
November 2008

Problems and perspectives for Chagas disease control: in search of a realistic analysis.

Rev Soc Bras Med Trop 2008 Mar-Apr;41(2):193-6

Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, MG.

Chagas disease was an important medical and social problem in almost all of Latin America throughout the twentieth century. It has been combated over a broad swath of this continent over recent decades, with very satisfactory results in terms of vector and transfusional transmission. Today, a surveillance stage still remains to be consolidated, in parallel with appropriate care required for some millions of infected individuals who are today living in endemic and non-endemic areas. Contradictorily, the good results attained have generated excessive optimism and even disregard among health authorities, in relation to this disease and its control. The loss of visibility and priority may be a logical consequence, particularly in Latin American healthcare systems that are still disorganized and overburdened due to insufficiencies of financial and human resources. Consolidation of the victories against Chagas disease is attainable but depends on political will and continual attention from the most consequential protagonists in this struggle, especially the Latin American scientific community.
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http://dx.doi.org/10.1590/s0037-86822008000200012DOI Listing
November 2008

Low efficacy of azithromycin to treat cutaneous leishmaniasis in Manaus, AM, Brazil.

Rev Inst Med Trop Sao Paulo 2007 Jul-Aug;49(4):235-8

Curso de Pós-Graduação em Medicina Tropical e Infectologia, Universidade Federal do Triângulo Mineiro, Uberaba, MG, Brasil.

An open trial to evaluate the azithromycin efficacy in cutaneous leishmaniasis patients was carried out in Manaus (AM), where Leishmania (Viannia) guyanensis is the main etiologic agent. Forty-one patients with skin lesions of less than 12 weeks duration, without specific treatment for the last three months and a positive imprint to Leishmania sp. were included. From these, 31 (75.6%) were male with median age of 30.2. All of them received a daily-single oral dose of 500 mg of azithromycin for ten days. At 25th day, 16 (39%) presented therapeutic failure and received intramuscular pentavalent antimonial, four were considered lost, 21, that had improved or were inaltered received another ten-day series of azithromycin and were monthly followed, but nine (21.9%) of them presented a poor clinical response and switched to intramuscular pentavalent antimonial on day 55. Of the 12 remaining cases evaluated on day 55, despite of clinical improvement, three asked for antimony therapy and 9 (21.9%) continued the follow-up but, only three were cured on 55th, 85th and 115 th days, and six did not come back for final evaluation. The intention-treatment overall response rate was 22% and whole cure was seen in three (7.3%) of cases. Thus, azithromycin showed a low efficacy to treat cutaneous leishmaniasis in Manaus.
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http://dx.doi.org/10.1590/s0036-46652007000400008DOI Listing
March 2008

Cardiac autonomic modulation evaluated by heart interval variability is unaltered but subtly widespread in the indeterminate Chagas' disease.

Pacing Clin Electrophysiol 2007 Jun;30(6):772-80

Faculty of Medicine of Triângulo Mineiro, Division of Tropical Medicine, Uberaba, MG, Brazil.

Background: Cardiac autonomic function in the indeterminate chronic form of Chagas' disease deserves better clearing-up and understanding, since the existing findings are scarce and controversial. This work analyzed the short-term heart interval variability in order to verify the cardiac autonomic modulation in indeterminate Chagas' disease subjects examined in a Brazilian endemic area.

Methods: Variability in time and frequency domain of 5-minute electrocardiogram (ECG) series of R-R intervals in supine and active standing positions were obtained from 18 age-, gender-, body mass index-, lifestyle-, and physical activity-matched chagasics and 18 control healthy subjects examined in Agua Comprida city, MG, Brazil. Mann-Whitney test was used for analysis of the data and spread of the individual indices in both groups.

Results: The median of the all variability indices in the chagasic group were statistically similar (P= 0.17-0.87) to that in the control group. A wide dispersion of the almost all individual indices values, ranging from normal to variably reduced or increased ones, was noted in the majority of the chagasics in relation to the control interquartile range, in both postural positions.

Conclusion: As a group, indeterminate Chagas' disease subjects showed unaltered short-term heart interval variability. Individual somewhat widespread of majority of time- and frequency-domain indices, from depressed to exacerbated ones appears to exist. This conforms to a variable cardiac autonomic modulation in this form of disease, suggesting that the majority of chagasics has no lesions, and a minority has subtle lesions of the efferent innervation-sinus node complex.
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http://dx.doi.org/10.1111/j.1540-8159.2007.00749.xDOI Listing
June 2007