Pathology of Chronic Chagas Cardiomyopathy in the United States: A Detailed Review of 13 Cardiectomy Cases.

OBJECTIVES: The pathologic features of chronic Chagas cardiomyopathy may not be widely appreciated in the United States. We sought to describe the gross, microscopic, immunohistochemical, and molecular pathology features useful to diagnose chronic Chagas cardiomyopathy. METHODS: The features from a case series of cardiectomy specimens of patients undergoing heart transplantation (12 patients) or mechanical circulatory support device implantation (one patient) for chronic Chagas cardiomyopathy at three institutions in the United States are reported and analyzed. RESULTS: Gross findings included enlarged and dilated ventricles (100% of cases), mural thrombi (54%), epicardial plaques (42%), and left ventricular aneurysm (36%). Microscopic evaluation revealed myocarditis (100% of cases) characterized by mononuclear cell infiltration, fibrosis (100%), nonnecrotizing granulomas (62%), and giant cells (38%). Two specimens (15%) showed rare intracellular amastigotes. Immunohistochemical assays for Trypanosoma cruzi organisms were negative in all cardiectomy specimens, whereas tissue polymerase chain reaction was positive in six (54%) of 11 cases. CONCLUSIONS: The gross and microscopic features of chronic Chagas cardiomyopathy in the United States appear similar to those reported in endemic countries. Importantly, tissue polymerase chain reaction may be useful to confirm the diagnosis.

Do Archaea and bacteria co-infection have a role in the pathogenesis of chronic chagasic cardiopathy?

UNLABELLED: Chronic cardiopathy (CC) in Chagas disease is a fibrotic myocarditis with C5b-9 complement deposition. Mycoplasma and Chlamydia may interfere with the complement response. Proteolytic enzymes and archaeal genes that have been described in Trypanosoma cruzi may increase its virulence. Here we tested the hypothesis that different ratios of Mycoplasma, Chlamydia and archaeal organisms, which are frequent symbionts, may be associated with chagasic clinical forms. MATERIALS AND METHODS: eight indeterminate form (IF) and 20 CC chagasic endomyocardial biopsies were submitted to in situ hybridization, electron and immunoelectron microscopy and PCR techniques for detection of Mycoplasma pneumoniae (MP), Chlamydia pneumoniae(CP), C5b-9 and archaeal-like bodies. RESULTS: MP and CP-DNA were always present at lower levels in CC than in IF (p < 0.001) and were correlated with each other only in CC. Electron microscopy revealed Mycoplasma, Chlamydia and two types of archaeal-like bodies. One had electron dense lipid content (EDL) and was mainly present in IF. The other had electron lucent content (ELC) and was mainly present in CC. In this group, ELC correlated negatively with the other microbes and EDL and positively with C5b-9. The CC group was positive for Archaea and T. cruzi DNA. In conclusion, different amounts of Mycoplasma, Chlamydia and archaeal organisms may be implicated in complement activation and may have a role in Chagas disease outcome.

Do Archaea and bacteria co-infection have a role in the pathogenesis of chronic chagasic cardiopathy?

Chronic cardiopathy (CC) in Chagas disease is a fibrotic myocarditis with C5b-9 complement deposition. Mycoplasma and Chlamydia may interfere with the complement response. Proteolytic enzymes and archaeal genes that have been described in Trypanosoma cruzi may increase its virulence. Here we tested the hypothesis that different ratios of Mycoplasma, Chlamydia and archaeal organisms, which are frequent symbionts, may be associated with chagasic clinical forms. MATERIALS AND METHODS: eight indeterminate form (IF) and 20 CC chagasic endomyocardial biopsies were submitted to in situ hybridization, electron and immunoelectron microscopy and PCR techniques for detection of Mycoplasma pneumoniae (MP), Chlamydia pneumoniae(CP), C5b-9 and archaeal-like bodies. RESULTS: MP and CP-DNA were always present at lower levels in CC than in IF (p < 0.001) and were correlated with each other only in CC. Electron microscopy revealed Mycoplasma, Chlamydia and two types of archaeal-like bodies. One had electron dense lipid content (EDL) and was mainly present in IF. The other had electron lucent content (ELC) and was mainly present in CC. In this group, ELC correlated negatively with the other microbes and EDL and positively with C5b-9. The CC group was positive for Archaea and T. cruzi DNA. In conclusion, different amounts of Mycoplasma, Chlamydia and archaeal organisms may be implicated in complement activation and may have a role in Chagas disease outcome.

Alterations in myocardial gene expression associated with experimental Trypanosoma cruzi infection.

Chagas disease, characterized by acute myocarditis and chronic cardiomyopathy, is caused by infection with the protozoan parasite Trypanosoma cruzi. We sought to identify genes altered during the development of parasite-induced cardiomyopathy. Microarrays containing 27,400 sequence-verified mouse cDNAs were used to analyze global gene expression changes in the myocardium of a murine model of chagasic cardiomyopathy. Changes in gene expression were determined as the acute stage of infection developed into the chronic stage. This analysis was performed on the hearts of male CD-1 mice infected with trypomastigotes of T. cruzi (Brazil strain). At each interval we compared infected and uninfected mice and confirmed the microarray data with dye reversal. We identified eight distinct categories of mRNAs that were differentially regulated during infection and identified dysregulation of several key genes. These data may provide insight into the pathogenesis of chagasic cardiomyopathy and provide new targets for intervention.

[Anti-sulfatide antibody titers in patients with chronic Chagas disease and other forms of cardiopathy]. / Títulos de anticuerpos antisulfátido en pacientes con cardiopatía chagásica crónica y con otras formas de cardiopatía.

A specific treatment for Chagas' disease has not yet been discovered, even though the condition is endemic in large parts of the Region of the Americas. Earlier studies have addressed the possibility that the sulfatide galactocerebroside in Trypanosoma cruzi behaves as an immunogen involved in the production of the high antisulfatide antibody levels found in patients with chronic infestation with the parasite. This may be an important factor in the pathogenesis of the cardiac symptoms and peripheral neuropathy seen in Chagas' disease, which is the most important cause of myocarditis in Central and South America and the second most important cause of heart failure in several of the countries located in these subregions. The present study was conducted in order to ascertain whether patients with Chagas' disease and other patients not afflicted with the ailment differ insofar as the presence of antibodies against sulfatide is concerned, and it describes antisulfatide antibody levels in 124 hospital patients (74 men and 50 women) between the ages of 15 and 94 who were in the cardiology unit of Vargas Hospital in Caracas from 1 July to 30 June 1995. Antisulfatide antibody titers were determined by means of enzyme-linked immunosorbent assays (ELISA), and the antigen employed was sulfatide cerebroside obtained from bovine brain tissue. Of the 124 patients under study, 39 (31.5%) suffered from Chagas' disease and had antisulfatide antibody levels higher than those detected in patients without Chagas (P = 0.0298) and in 28 seemingly healthy controls (P = 0.0035). Serum levels of antisulfatide antibodies in patients with other forms of heart disease were also compared with those seen in the control group, and significantly higher levels were found in patients with acute ischemic heart disease (P = 0.0049), rheumatic valvular heart disease (P = 0.0075), chronic ischemic heart disease (P = 0.0464) and bradiarrythmias (P = 0.0157), and significantly lower ones in subjects with hypertensive heart disease (P = 0.0367). These antibody levels showed no correlation with clinical or paraclinical variables indicative of the degree of cardiac compromise. Our results support the notion that antibodies against sulfatide may play a role in the pathogenesis of Chagas' cardiomyopathy and other forms of heart disease and should be further studied in an effort to determine their potential role in these processes.