Clinical Forms Of Chagas Disease Research Articles

Foxp3+CD25high CD4+ regulatory T cells from indeterminate patients with Chagas disease can suppress the effector cells and cytokines and reveal altered correlations with disease severity

Immunoregulatory mechanisms are important to control the intense immune activity induced in Chagas disease. We evaluated the phenotypic profile and the mechanisms by which Treg cells function in patients with the indeterminate (IND) and cardiac (CARD) clinical forms of Chagas disease. The frequency of Foxp3+CD25high CD4+-T cells is augmented and correlated with the maintenance of a better cardiac function in IND. Treg cells from IND present suppressive activity, although the mechanism is not IL-10 or CTLA-4 dependent and are able to produce augmented levels of IL-17, IL-10 and granzyme B being its frequency correlated with percentage of Annexin V+ CD4+-cells. In contrast, CARD presents higher frequency of IL-6+, IFN-gamma+, TNF-alpha+ and CTLA-4+ Treg-cells than IND. Thus, our data suggest that Treg cells have an important role in controlling the exacerbated immune response and morbidity in Trypanosoma cruzi infection, probably modulating the cytokine environment and/or killing effector cells.

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

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. 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. 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). 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.

Impaired phagocytic capacity driven by downregulation of major phagocytosis-related cell surface molecules elicits an overall modulatory cytokine profile in neutrophils and monocytes from the indeterminate clinical form of Chagas disease

The distinct ability of phagocytes to present antigens, produce cytokines and provide co-stimulatory signals may contribute to the severity of the outcome of Chagas disease. In this paper, we evaluate the phenotypic features of phagocytes along with the cytokine signature of circulating T-cells from Chagas disease patients with indeterminate (IND) and cardiac (CARD) clinical forms of the disease. Our data demonstrated that neutrophils from IND patients displayed an impaired ability to produce cytokines. A lower Trypanosoma cruzi phagocytic index and higher nitric oxide levels were characteristics of monocytes from IND. The impaired phagocytic capacity did not reflect on the levels of anti-T. cruzi IgG, but was detectable in the downregulation of Fc-γR, TLR and CR1 molecules. The monocyte-derived cytokine signature demonstrated that a down-regulated synthesis of IL-12 and a modulatory state were evidenced by a positive correlation between IL-12 and IL-10 with a lower synthesis of TNF-α. The down-regulation of MHC-II and CD86 in monocytes supports the occurrence of particularities in the APC-activation-arm in IND, and may be involved in the T-cell pro-inflammatory pattern counterbalanced by a potent IL-10 response. Our findings support the hypothesis that differential phenotypic features of monocytes from IND may be committed to the induction of a distinct immune response related to low morbidity in chronic Chagas disease.

Differential expression of Trypanosoma cruzi I associated with clinical forms of Chagas disease: Overexpression of oxidative stress proteins in acute patient isolate

Chagas disease has a variable clinical course with different manifestations and heterogenous geographical distribution. Some studies suggest that this clinical variability could be influenced by the genetic variability of T. cruzi. Here we present the differential protein expression among trypomastigotes and amastigotes of T. cruzi group I isolates from patients with acute and chronic form of Chagas disease from Santander, Colombia. A total of 29 proteins were identified by MALDI-TOF and LC-MS/MS; twenty in trypomastigote and nine in amastigote stage. The 29 proteins identified were grouped in 7 functional categories: 1) metabolism 31%, 2) assembly of cytoskeleton 13.7%, 3) protein destination 13.7%, 4) defenses antioxidants 20.6%, 5) protein synthesis and cellular cycle 13.7%, 6) catabolism 6.8%, and 7) adhesion 3.4%. Tryparedoxin peroxidase, lipoamide dehydrogenase, tyrosine amino transferase and HSP70 were overexpressed in the acute Chagas isolate. Tryparedoxin peroxidase overexpression in the acute isolate was confirmed by Western blot analysis. Most of these proteins are associated with resistance to oxidative stress facilitating their survival within host cells. Therefore, these proteins may represent virulence factors associated with the development of the acute form of the disease and could be used as biomarkers of the clinical course of disease and as drug targets.

Immunoglobulin M antibodies against CRA and FRA recombinant antigens of Trypanosoma cruzi in chronic chagasic patients

Previous works of our research group have demonstrated aspects of the humoral immune response of chronic Chagas disease using the cytoplasmatic repetitive antigen (CRA) and the flagellar repetitive antigen (FRA) of Trypanosoma cruzi. The aim of this work was to analyze the presence of specific immunoglobulin M (IgM) antibodies in chronic chagasic patients using these recombinant antigens of T. cruzi. The positivity of IgM in chronic chagasic patients against CRA and FRA antigens was determined by indirect enzyme-linked immunosorbent assay. We reported no statistical significant differences between the levels of IgM for both recombinant antigens and the different chronic clinical forms of Chagas disease. However, a small proportion of chronic chagasic patients analyzed in this study was positive for this antibody isotype. The findings of this study indicate that the IgM antibodies cannot be used to elucidate the differences in the profile of humoral immune response among chronic chagasic patients with different clinical forms using the CRA and FRA recombinant antigens of T. cruzi.

Cytokine Levels in Serious Cardiopathy of Chagas Disease After In Vitro Stimulation with Recombinant Antigens from Trypanosoma cruzi

The clinical manifestations of human Chagas disease are associated with distinct and complex host-parasite interactions that directly involve the host's immune system. In this study, we analysed the relationship between the production of intracytoplasmic cytokines after in vitro stimulation with the recombinant antigens CRA (cytoplasmatic repetitive antigen) or FRA (flagellar repetitive antigen) from Trypanosoma cruzi and the chronic cardiac or indeterminate clinical forms of Chagas disease. The chagasic patient groups consisted of 39 individuals, selected at the Chagas Disease Unit of the Oswaldo Cruz University Hospital, whom presented either a cardiac form without cardiac dilatation (CARD 1), cardiac form with cardiac dilatation (CARD 2) or indeterminate form (IND). Blood samples were obtained from these patients and cultured in the presence of CRA or FRA. The cytokines produced by lymphocytes and monocytes after antigen stimulation were analysed by flow cytometry. Our results showed that the IFN-γ and TNF-α, produced by CD8+ T lymphocytes after in vitro stimulation with CRA, differed among chagasic patients with CARD 1, CARD 2 or IND. We propose that these cytokines could be utilized as immunological markers for clinical cardiac forms of Chagas disease. In a prospective study of patients presenting IND and CARD 1, the assay performed in this paper could serve as a tool to monitor therapeutic interventions, thus improving the patient's quality of life.

Increased levels of IgA antibodies against CRA and FRA recombinant antigens of Trypanosoma cruzi differentiate digestive forms of Chagas disease

In the chronic phase of Chagas disease, individuals infected by Trypanosoma cruzi may be asymptomatic or may present cardiac and/or digestive complications. Our aim here was to analyze the relationship between the presence of specific immunoglobulin A antibodies and the different chronic clinical forms of Chagas disease using two recombinant antigens of Trypanosoma cruzi, cytoplasmatic repetitive antigen and flagellar repetitive antigen. The association of this immunoglobulin isotype with the digestive and cardio-digestive forms of the disease determined by indirect enzyme-linked immunosorbent assay, strongly suggests that IgA antibodies against these recombinant antigens of T. cruzi can be used as an immunological marker of the digestive alterations caused by Chagas disease. The tests performed in this study show that it is possible to differentiate digestive forms of Chagas disease. The knowledge provided by these results may help physicians to manage early alterations in the digestive tract of patients with the indeterminate or cardiac forms of Chagas disease. Prospective studies, however, with follow-up of the patients that presenting with high levels of immunoglobulin A against cytoplasmatic repetitive antigen and flagellar repetitive antigen recombinant antigens, need to be conducted to confirm this hypothesis.

Chagasic megacolon associated with Trypanosoma cruzi I in a Colombian patient

Chagasic megacolon has been reported in the southern cone countries of South America and is mainly associated with Trypanosoma cruzi II infection. Herein, we report the first case in Colombia of chagasic megacolon with cardiomyopathy associated with the T. cruzi I lineage. This finding suggests that in Colombia, as well as in other northern countries of South America and throughout Central America, where T. cruzi I is endemic, cardiomyopathy may not be the only clinical form of Chagas disease.

Profile of Central and Effector Memory T Cells in the Progression of Chronic Human Chagas Disease

BackgroundChronic Chagas disease presents several different clinical manifestations ranging from asymptomatic to severe cardiac and/or digestive clinical forms. Several studies have demonstrated that immunoregulatory mechanisms are important processes for the control of the intense immune activity observed in the chronic phase. T cells play a critical role in parasite specific and non-specific immune response elicited by the host against Trypanosoma cruzi. Specifically, memory T cells, which are basically classified as central and effector memory cells, might have a distinct migratory activity, role and function during the human Chagas disease.Methodology/Principal FindingsBased on the hypothesis that the disease severity in humans is correlated to the quality of immune responses against T. cruzi, we evaluated the memory profile of peripheral CD4+ and CD8+ T lymphocytes as well as its cytokine secretion before and after in vitro antigenic stimulation. We evaluated cellular response from non-infected individuals (NI), patients with indeterminate (IND) or cardiac (CARD) clinical forms of Chagas disease. The expression of CD45RA, CD45RO and CCR7 surface molecules was determined on CD4+ and CD8+ T lymphocytes; the pattern of intracellular cytokines (IFN-γ, IL-10) synthesized by naive and memory cells was determined by flow cytometry. Our results revealed that IND and CARD patients have relatively lower percentages of naive (CD45RAhigh) CD4+ and CD8+ T cells. However, statistical analysis of ex-vivo profiles of CD4+ T cells showed that IND have lower percentage of CD45RAhigh in relation to non-infected individuals, but not in relation to CARD. Elevated percentages of memory (CD45ROhigh) CD4+ T cells were also demonstrated in infected individuals, although statistically significant differences were only observed between IND and NI groups. Furthermore, when we analyzed the profile of secreted cytokines, we observed that CARD patients presented a significantly higher percentage of CD8+CD45RAhigh IFN-γ-producing cells in control cultures and after antigen pulsing with soluble epimastigote antigens.ConclusionsBased on a correlation between the frequency of IFN-γ producing CD8+ T cells in the T cell memory compartment and the chronic chagasic myocarditis, we propose that memory T cells can be involved in the induction of the development of the severe clinical forms of the Chagas disease by mechanisms modulated by IFN-γ. Furthermore, we showed that individuals from IND group presented more TCM CD4+ T cells, which may induce a regulatory mechanism to protect the host against the exacerbated inflammatory response elicited by the infection.

Plasma concentrations of tumour necrosis factor‐alpha, tumour necrosis factor‐related apoptosis‐inducing ligand, and FasLigand/CD95L in patients with Chagas cardiomyopathy correlate with left ventricular dysfunction

Cardiomyocyte apoptosis is reported to be involved in the pathogenesis of human chronic Chagas cardiomyopathy (CCC). Members of the tumour necrosis factor (TNF) superfamily (TNF-alpha, FasLigand/CD95L, and TNF-related apoptosis-inducing ligand) are known to activate the death receptor pathway. We therefore investigated whether levels of TNF-alpha, FasLigand/CD95L, and TRAIL correlated with changes in heart function of patients with Chagas disease (n = 31). Concentrations of TNF-alpha and TRAIL were clearly augmented in individuals with severe form CCC (n = 16). Levels of FasLigand/CD95L were greater in chagasic patients than in non-infected individuals (n = 15) but did not differentiate between clinical forms of Chagas disease. There was a good correlation between TNF-alpha (r = 0.85 and r = 0.68, P < 0.0001) or TRAIL (r = 0.68 and r = 0.60, P < 0.001) and left ventricular ejection fraction (LVEF) and left ventricular diastolic diameter (LVDD), respectively. In addition, TNF-alpha (r = 0.57, P = 0.0001), TRAIL (r = 0.56, P = 0.001), and FasLigand/CD95L (r = 0.51, P = 0.001) showed a good correlation with brain natriuretic peptide, a well-known parameter of ventricular dysfunction in CCC. There was a weak correlation between levels of FasLigand/CD95L (r = 0.50, P < 0.004) and both LVEF and LVDD. There was no correlation between levels of TNF superfamily ligands and chronotropic incompetence, maximal heart rate, or number of ventricular premature beats in 24 h. Plasma levels of TNF superfamily ligands are elevated in patients with functional but not arrhythmogenic disturbances, and these death receptor ligands may be potential markers of ventricular dysfunction in CCC.

Immunological imbalance between IFN-³ and IL-10 levels in the sera of patients with the cardiac form of Chagas disease

The immune response is crucial for protection against disease; however, immunological imbalances can lead to heart and digestive tract lesions in chagasic patients. Several studies have evaluated the cellular and humoral immune responses in chagasic patients in an attempt to correlate immunological findings with clinical forms of Chagas disease. Moreover, immunoglobulins and cytokines are important for parasitic control and are involved in lesion genesis. Here, cytokine and IgG isotype production were studied, using total epimastigote antigen on sera of chagasic patients with indeterminate (IND, n = 27) and cardiac (CARD, n = 16) forms of the disease. Samples from normal,uninfected individuals (NI, n = 30) were use as controls. The results showed that sera from both IND and CARD patients contained higher levels of Trypanosoma cruzi-specific IgG1 (IgG1) antibodies than sera from NI. No difference in IgG2 production levels was observed between NI, IND and CARD patients, nor was a difference in IL-10 and IFN-gamma production detected in the sera of IND, CARD and NI patients. However, IND patients displayed a positive correlation between IL-10 and IFN-gamma levels in serum, while CARD patients showed no such correlation, indicating an uncontrolled inflammatory response in CARD patients. These findings support the hypothesis that a lack of efficient regulation between IFN-gamma and IL-10 productions in CARD patients may lead to cardiac immunopathology.

Strategy to Assess the Overall Cytokine Profile of Circulating Leukocytes and its Association with Distinct Clinical Forms of Human Chagas Disease

Herein we have employed an alternative strategy to assess the cytokine patterns of circulating leukocytes and correlate dominant cytokine profiles with indeterminate-IND and cardiac-CARD clinical forms of Chagas disease. We have first calculated median percentages of cytokine-positive leukocytes of our study sample to establish, for each cytokine-positive cell population, the cut-off edge that would segregate 'low' and 'high' cytokine producers to build colour diagrams and draw a panoramic cytokine chart. Using this approach we demonstrated that most IND individuals presented a dominant regulatory cytokine profile, whereas CARD individuals displayed a dominant inflammatory cytokine pattern. In addition, radar chart analysis confirmed the dichotomic cytokine balance between IND and CARD groups and further allowed the identification of the relative contribution of each cell population for the global cytokine pattern. Data analysis demonstrated that CD4+ T cells were the major cell population defining the regulatory profile in IND, whereas monocytes and CD4+ T cells determined the inflammatory cytokine pattern in CARD individuals. Interestingly, in vitro stimulation with trypomastigote Trypanosoma cruzi antigen was able to invert the cytokine balances in IND and CARD groups. Upon antigenic stimulation, changes in the frequencies of IL-10-producing CD4+ T cells and monocytes drove IND individuals towards an inflammatory pattern and CARD towards a regulatory cytokine profile. A similar inversion could be found after in vivo treatment of IND and CARD individuals with benzonidazole. Altogether, these findings shed some light into the complex cytokine network underlying the immunopathogenesis of Chagas disease and provide putative immunological biomarkers of disease severity and therapeutic response.

Implications of genetic variability of Trypanosoma cruzi for the pathogenesis of Chagas disease

Trypanosoma cruzi, the etiological agent of Chagas disease, presents a high degree of intraspecific genetic variability, with possible implications for the clinical forms of the disease, like the development of cardiopathy, megaesophagus, and megacolon, alone or in combination. This tissue tropism involved in the pathogenesis of Chagas disease has still not been totally elucidated. Thus, the current review approaches key aspects of T. cruzi genetic diversity, the clinical forms of Chagas disease, and the infection of the host cell by the parasite and the immune response. Other aspects discussed here include the release of immunosuppressive factors by the parasite, acting in the host's immune response pathways; host cell apoptosis inhibition; the pathogenesis of chagasic megaesophagus, which can be related to host-parasite interaction; and finally the association between megaesophagus and increased risk for the development of squamous-cell esophageal carcinoma. However, despite great advances in the understanding of this disease, it is still not possible to establish the true relationship between the parasite's genetic variability and the clinical form of Chagas disease.

Freqüência da hipertensão arterial em chagásicos crônicos e sua repercussão no coração: estudo clínico e anatomopatológico

Data from the literature on the frequency of concomitant Chagas disease and hypertension are controversial and, when available, do not mention the consequences of this concomitance in the natural history of either Chagas disease or of hypertension. To assess the frequency of concomitant Chagas disease and hypertension and the clinical and anatomopathological consequences of this association. The cases were selected from necropsies performed in the Department of Pathological Anatomy of Hospital e Maternidade Celso Pierrô of Pontifícia Universidade Católica de Campinas and divided into three groups: CH + SH group, of patients with Chagas disease plus hypertension; CH group, of patients with Chagas disease without hypertension; and SH group, of patients with hypertension without Chagas disease. The variables of gender, age, race, clinical forms of Chagas disease, and electrocardiographic and anatomopathological findings were statistically analyzed. In this assessment, a total of 101 (2.9%) cases of patients with Chagas disease was found, and 33 (32.7%) of them also had hypertension. A slight predominance of the male gender was observed; racial distribution and mean age were similar in the three groups. Severe hypertension was not frequently found among chagasic patients. When present, hypertension did not change the clinical and anatomopathological findings compatible with Chagas disease. The frequency of hypertension in chagasic patients was similar to that observed in the general population. Hypertension, when present in chagasic patients, occurred in those with a higher mean age. The concomitance of hypertension and Chagas disease did not change the natural history of either one of the two diseases.

Lack of association of tumor necrosis factor-α polymorphisms with Chagas disease in Brazilian patients

One third of Trypanosoma cruzi-infected individuals develop chronic Chagas disease cardiomyopathy (CCC) while the majority remains asymptomatic (ASY). About 30% of CCC patients develop heart failure due to end-stage inflammatory dilated cardiomyopathy. Increased production of tumor necrosis factor (TNF)-α has been described in all clinical forms of Chagas disease, and the highest levels are detected in CCC patients with severe ventricular dysfunction. Genetic susceptibility may play a role in the clinical outcome of Chagas disease. We investigated TNF as a candidate gene for susceptibility to development and/or progression of CCC. We analyzed the TNFa microsatellite and the −308 TNF promoter polymorphisms, in 166 CCC compared to 80 ASY geographically and age-matched patients in an association study. To analyze the association of TNF polymorphisms with progression of the cardiomyopathy, CCC patients were also grouped in three categories according to degree of left ventricular (LV) dysfunction into severe ( n = 57), mild to moderate ( n = 21) and absent ( n = 88). Our results show no significant differences either between CCC and ASY patients, or among CCC patients according to severity of cardiomyopathy with respect to TNFa or −308 TNF promoter polymorphisms. These results indicate that TNF polymorphisms are associated neither to CCC development nor to progression to more severe forms of cardiomyopathy in Brazilian Chagas disease patients.

Differential transcription profiles in Trypanosoma cruzi associated with clinical forms of Chagas disease: Maxicircle NADH dehydrogenase subunit 7 gene truncation in asymptomatic patient isolates

The majority of individuals in the chronic phase of Chagas disease are asymptomatic (indeterminate form). Every year 2–3% of these individuals develop severe clinical manifestations (cardiac and digestive forms). In this study a Trypanosoma cruzi DNA microarray was used to compare the transcript profiles of six human isolates: three from asymptomatic and three from cardiac patients. Seven signals were expressed differentially between the two classes of isolates, including tryparedoxin, surface protease GP63, cyclophilin, some hypothetical proteins and the pre-edited maxicircle gene NADH dehydrogenase subunit 7 (ND7). The approximately 30-fold greater signal in cardiac strains for ND7 was the most pronounced of the group, and differential levels of pre-edited ND7 transcript confirmed the microarray analysis. The ND7 gene from asymptomatic isolates showed a deletion of 455bp from nt 222 to nt 677 relative to ND7 of the CL Brener reference strain. The ND7 gene structure correlated with disease manifestation for 20 isolates from clinically characterised, chronic phase patients. The ND7 lesion produces a truncated product that could impair the function of mitochondrial complex I. Possible links between the integrity of the electron transport chain and symptom presentation are discussed. We propose that ND7 and other genes of the pathway constitute valuable targets for PCR assays in the differential diagnosis of the infective T. cruzi strain. While this hypothesis requires validation by the examination of additional recent parasite isolates from patients with defined pathologies, the identification of specific molecular markers represents a promising advance in the association between parasite genetics and disease pathology.

Comparative analysis of cell phenotypes in different severe clinical forms of Chagas' disease

The understanding of the role of the immune response in the development of gastrointestinal and cardio-digestive (CD) forms of Chagas disease has received little attention. In this paper, the commitment of each leukocyte population of peripheral blood to the production of IFN-gamma, TNF-alpha, IL-12, IL-4, IL-5 and IL-10 was studied in patients with the CD form of Chagas disease. The data show that cells from patients with the CD form of the disease have distinct cytokine profiles when compared with the other clinical forms of Chagas disease and suggest that eosinophils are the major source of cytokine production in this clinical entity. The data presented in this paper demonstrate that patients with CD form can be distinguished from patients with gastrointestinal or cardiac forms of the disease by the distinct cytokine profile of peripheral blood cells.

Use Of S(+)-Ketamine In A Patient With Chronic Chagasic Cardiopathy For Emergency Cardiac Defibrillation Procedure

Among the chronic clinical forms of Chagas disease, the anesthesiologists must pay attention to the chagasic cardiomyopathy, since the drugs used in anesthesia, in its majority, act like depressors of the cardiac function. A male 66 year-old patient presented with chronic chagasic cardiomyopathy (left ventricle ejection fraction of 34%). We admnistered continuous IV dobutamine and amiodarone. He presented with ventricular tachycardia associated to hypoxemia, pulmonary oedema and arterial hypotension, making necessary an emergency cardiac defibrillation procedure. Since this patient was found in cardiac and respiratory failure, S(+)-ketamine was administered and then 200J was applied for external defibrillation. Cardiac rhythm converted to sinus type. The patient did not recall the event. Etomidate and vecuronium are being used in patients with chagasic cardiopathy presenting satisfactory results. The use of S(+)-ketamine should be studied in this patients to determine its safety.

Biodemes of Trypanosoma cruzi strains isolated from humans from three endemic areas in Minas Gerais State

In order to study the biological behavior of T. cruzi strains and to determine a putative association between their biodeme and the clinical forms of Chagas disease, 14 strains isolated from humans were evaluated. The individuals were from the municipalities of Pains, Iguatama and Berilo (Minas Gerais State). The biological behavior was evaluated in albino swiss mice, weighing 10 to 15 grams, which were infected with 1x10(4) blood tripomastigotes. The infectivity, parasitemia, tripomastigote morphology, virulence and the tissue distribution of the protozoan were analyzed. A behavior similar to biodeme II (São Felipe strain) was observed in 9 strains, while 5 stocks were characterized as belonging to biodeme III. It was not possible to establish a relationship between the biodeme strain and the severity of the disease in the patients.

Genetic Characterization of Trypanosoma cruzi Directly from Tissues of Patients with Chronic Chagas Disease : Differential Distribution of Genetic Types into Diverse Organs

We have previously shown that a low-stringency single-specific primer-polymerase chain reaction (LSSP- PCR) is a highly sensitive and reproducible technique for the genetic profiling of Trypanosoma cruzi parasites directly in tissues from infected animals and humans. By applying LSSP-PCR to the study of the variable region of kinetoplast minicircle from T. cruzi, the intraspecific polymorphism of the kinetoplast-deoxyribonucleic acid (kDNA) sequence can be translated into individual kDNA signatures. In the present article, we report on our success using the LSSP-PCR technique in profiling the T. cruzi parasites present in the hearts of 13 patients with chagasic cardiopathy and in the esophagi of four patients (three of them with chagasic megaesophagus). In two patients, one with the cardiodigestive clinical form of Chagas disease and the other with cardiopathy and an esophageal inflammatory process, we could study both heart and esophagus and we detected distinct kDNA signatures in the two organs. This provides evidence of a differential tissue distribution of genetically diverse T. cruzi populations in chronic Chagas disease, suggesting that the genetic variability of the parasite is one of the determining factors of the clinical form of the disease.