Involvement of the autonomic nervous system in Chagas heart disease

The autonomic nervous system and especially the intracardiac autonomic nervous system is involved in Chagas' disease. Ganglionitis and periganglionitis were noted in three groups ofpatients dying with Chagas'disease: 1) Those in heart failure; 2) Those dying a sudden, non violent death and; 3) Those dying as a consequence ofaccidents or homicide. Hearts in the threegroups also revealed myocarditis and scattered involvement of intramyocardial ganglion cells as well as lesions of myelinic and unmyelinic fibers ascribable to Chagas'disease. In mice with experimentally induced Chagas' disease weobserved more intensive neuronal lesions of the cardiac ganglia in the acute phase of infection. Perhaps neuronal loss has a role in the pathogenesis of Chagas cardiomyopathy. However based on our own experience and on other data from the literature we conclude that the loss of neurones is not the main factor responsible for the manifestations exhibited by chronic chagasic patients. On the other hand the neuronal lesions may have played a role in the sudden death ofone group of patients with Chagas'disease but is difficult to explain the group of patients who did not die sudderly but instead progressed to cardiac failure.

Pathology of complete atrioventricular block in chronic chagas' myocarditis

Sclero-atrophy, fibrosis, vascular ectasia, phlebosclerosis and mild non-specific chronic inflammatory changes were observed in variable location and proportion involving the atrioventricular conducting tissue of the heart in five human cases of chronic Chagas' myocarditis associated with complete atrioventricular block. One case presented complete destruction of the A-V conduction system. In three cases the lesions were disseminated all along the conducting tissue but did not cause anywhere a complete disruption in the continuity of the system. The distal portion of the bundle branches were the most damaged sector of the system, exceptfor the fasciculi of the posterior division of the left bundle branch which were relatively preserved. One case exhibited bilateral sclero-atrophy of the bundle branches as the main change; and another showed early and mild fibrocalcific damage of the penetrating portion of the His bundle. The A-V node appeared as the least involved part of the conducting system in the cases studied. Demonstration of the lesions in this series of cases seems important because: a) it reveals that complete atrioventriculr block in chronic Chagas' disease results from disseminated lesions and not from focal disruptive change as has been commonly observed in cases of other etiologies; b) it shows that chronic inflammation can produce at the end variable and widespread vascular, degenerative andfibrotic alterations within the conducting tissue of the heart, which may lead to its total destruction.

Frequency of myocarditis in cases of fatal meningococcal infection in children: observations on 31 cases studied at autopsy

The frequency of myocarditis associated with meningococcal disease in children was reported only in two autopsied series (United States and South Africa). Here we report the frequency of associated myocarditis in 31 children who died of meningoccal infection at Hospital Infantil N.S. da Glória in Vitória, Espirito Santo State, Brazil. The diagnosis was confirmed by isolation of Neisseria meningitidis . At least three sections of fragments of both atria and ventricles were studied using the Dallas Criteria for the morphologic diagnosis of myocarditis. The mean age was 47.6 ± 39.8 months and the mean survival time after the onset of symptoms was 46.1 ± 26.5h (12-112h). Myocarditis was present in 13 (41.9%) patients, being of minimal severity in 11 cases and of moderate severity in 2 cases. There were no cases with severe diffuse myocarditis. The frequency of myocarditis was not influenced by sex, presence of meningitis, survival time after the onset of symptoms or use of vasoactive drugs. The frequency of myocarditis reported here was intermediate between the values reported in the only two case series published in the literature (57% in the United States and 27% in South Africa). Although our data confirm the high frequency of myocaditis in meningoccal disease, further investigations are necessary to elucidate the contribution of myocarditis to myocardial dysfunction observed in cases of meningococcal infection in children.

Absence of both circadian rhythm and Trypanosoma cruzi periodicity with xenodiagnosis in chronic chagasic individuals

Xenodiagnoses were performed every 3 hours using 10 Triatoma infestans 3rd instar for 24 to 72 hours, in 18 chronic chagasics with positive serology and/or xenodiagnosis. There was no statistically significant difference in the positivity of assays performed during the day (9:00 to 18:00h) compared to those performed at night (21:00 to 6:00h), (chi² = 0.1526 p = 0.696). Xenodiagnosis was performed in ten of the patients for 13 successive days but there was no periodicity detected in the positive assays.

Hepatocyte metaplasia in experimental chagasic pancreatitis: preliminary report

Beginning the study of chronic pathologic changes in pancreas of hamsters experimentally infected with Trypanosoma cruzi Vic strain, hepatocyte metaplasia was observed in one animal from infected group. This is the first report of oncocytes in Chagas' disease, which could be due to aberrant regenerative response to pancreas inflammatory process.

Association of chagasic megacolon and cancer of the colon: case report and review of the literature

There are few descriptions of association between chagasic megacolon and colon cancer. We report a case of obstructive abdomen caused by adenocarcinoma of the left colon in chagasic megacolon. A review of the literature revealed 8 cases of this association and, analyzing together the series of findings of cancer in chagasic organomegalies, we found a frequency of 4.8% in megaesophagus and 0.1% in megacolon.

Cardiovascular function in elderly patients with chronic chagasic cardiopathy

The objective of this work was to verify the degree and type of heart damage of elderly chagasic patients seen at an outpatient referral center and to compare them with the changes found in young chagasic patients with a similar degree of heart damage. Elderly and young patients without advanced cardiopathy presented good functional behavior. Elderly patients with advanced cardiopathy had more ventricular premature beats (VPB) in 24 h and less functional capacity in the exercise test than young patients of the same subgroup. There was a higher occurrence of effort-induced VPB and a lower prevalence of severe forms in elderly men, suggesting that Chagas' disease may have a worse evolution in males. The association of cardiac damage characteristic of aging with the secondary damage due to Chagas' disease could explain the greater functional damage found in elderly chagasic patients. Thus, it appears that the physiopathological components of Chagas' disease do have an influence on the clinical course of cardiopathy in the elderly population.

Chagasic enteropathy

Involvement of the hollow organs of the digestive apparatus can occur in patients in the chronic phase of Chagas' disease. The basic mechanism is destruction of neurons of the enteric nervous system. Whereas megaesophagus and megacolon are the most notable and most extensively studied expressions of the digestive form of Chagas' disease, involvement of the small intestine (Chagasic enteropathy) is less frequent and less known than involvement of the two above mentioned entities. Chagasic enteropathy can be responsible for important clinical and laboratory manifestations resembling those of dyspeptic syndrome, intestinal pseudo-obstruction and bacterial overgrowth in the small intestine. Chagasic enteropathy also involves peculiar functional changes, especially those related to motor activity of the organ and to intestinal absorption of carbohydrates. In practice, the diagnosis is based on radiographic documentation of dilation of visceral segments. Treatment consists of clinical control of the above syndromes and, eventually, appropriate surgical operations.

Reinfections with strains of Trypanosoma cruzi, of different biodemes as a factor of aggravation of myocarditis and myositis in mice

Reinfections with Trypanosoma cruzi in patients from endemic areas have been claimed to be an aggravation factor of cardiac manifestations in Chagas' disease. In the present study, the influence of triple infections with strains of different biodemes, on cardiac and skeletal muscle lesions was experimentally tested. Fifty eight mice chronically infected with the Colombian strain (Biodeme Type III) were successively reinfected as follows: 1st group - reinfected with 21 SF strain (Type II) followed by Y strain (Type I ); 2nd - group reinfections with Y strain followed by 21SF strain. Isoenzyme analysis of parasites from hemocultures obtained from triple infected mice, revealed the patterns of three distinct zymodemes in the same animal. Each Trypanosoma cruzi strain was reisolated after four passages in mice on either the 7th, 14th or 30th day after inoculation with the blood of triple infected mice. Histopathology results demonstrated a significant exacerbation of cardiac and skeletal muscle inflammatory lesions, confirmed by morphometric evaluation, in mice with triple infection. No aggravation of parasitism was detected. The possibility of an enhancement of cellular response in the triple infected mice is suggested.

Prolonged survival and immune reconstitution after chagasic meningoencephalitis in a patient with acquired immunodeficiency syndrome

We report a case of cerebral meningoencephalitis due to Trypanosoma cruzi in a patient with acquired immunodeficiency syndrome. The patient presented with seizures and focal neurological signs. Definitive diagnosis of chagasic meningoencephalitis was made by demonstration of free trypomastigote forms in the cerebrospinal fluid. Benznidazol was prescribed with clinical and neurological improvement. Antiretroviral drugs improved cellular immunity and three years later the patient presents a good clinical condition with immune reconstitution and undetectable viral load. Chagasic meningoencephalitis has a poor prognosis when specific treatment is not initiated or is delayed. A high index of diagnosis is necessary for early diagnosis and treatment, especially in endemic areas for Trypanosoma cruzi infection.

Prevalence of cholelithiasis in patients with chagasic megaesophagus

INTRODUCTION: The prevalence of cholelithiasis in the general population ranges from 9 to 18%. This prevalence is known to be higher in the presence of parasympathetic nerve damage of the biliary tract either due to surgery (vagotomy) or neuronal destruction (Chagas disease). The objective of this study was to evaluate the association of cholelithiasis and chagasic or idiopathic megaesophagus. METHODS: The ultrasound scans of 152 patients with megaesophagus submitted to cardiomyotomy and subtotal esophagectomy surgery were evaluated. The presence of cholelithiasis was compared between chagasic and idiopathic esophagopathy and ultrasound and clinical findings were correlated with age, sex and race. RESULTS: A total of 152 cases of megaesophagus, including 137 with chagasic megaesophagus and 15 with idiopathic megaesophagus, were analyzed. The mean age was 56.7 years (45-67) in the 137 patients with chagasic megaesophagus and 35.6 years (27-44) in the 15 cases of idiopathic megaesophagus, with a significant difference between the two groups (p < 0.0001). The group with chagasic megaesophagus consisted of 59 (43%) women and 78 (56.9%) men, while the group with idiopathic megaesophagus consisted of 8 (53.3%) women and 7 (46.6%) men, showing no significant difference between the groups. Of the 137 patients with confirmed chagasic megaesophagus, 39 (28.4%) presented cholelithiasis versus one case (6.6%) in the 15 patients with idiopathic megaesophagus. CONCLUSIONS: The prevalence of cholelithiasis is high in patients with chagasic megaesophagus and preoperative ultrasound should be performed routinely in these patients in order to treat both conditions during the same surgical procedure.

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

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.

Echocardiographic parameters associated with pulmonary congestion in outpatients with Chagas' cardiomyopathy and non-chagasic cardiomyopathy

INTRODUCTION: Despite significant left ventricular (LV) systolic dysfunction and cardiomegaly, pulmonary congestion does not seem to be a major finding in Chagas' cardiomyopathy (CC). This study sought to identify echocardiographic parameters associated with pulmonary congestion in CC and in dilated cardiomyopathy of other etiologies, such as non-CC (NCC), and to compare pulmonary venous hypertension between the two entities. METHODS: A total of 130 consecutive patients with CC and NCC, with similar echocardiographic characteristics, were assessed using Doppler echocardiography and chest radiography. Pulmonary venous vessel abnormalities were graded using a previously described pulmonary congestion score, and this score was compared with Doppler echocardiographic parameters. RESULTS: NCC patients were older than CC patients (62.4 ± 13.5 × 47.8 ± 11.2, p = 0.00), and there were more male subjects in the CC group (66.2% × 58.5%, p = 0.4). Pulmonary venous hypertension was present in 41 patients in the CC group (63.1%) and in 63 (96.9%) in the NCC group (p = 0.0), the mean lung congestion score being 3.2 ± 2.3 and 5.9 ± 2.6 (p = 0.0), respectively. On linear regression multivariate analysis, the E/e' ratio (β = 0.13; p = 0.0), LV diastolic diameter (β = 0.06; p = 0.06), left atrial diameter (β = 0.51; p = 0.08), and right ventricular (RV) end-diastolic diameter (β = 0.02; p = 0.48) were the variables that correlated with pulmonary congestion in both groups. CONCLUSIONS: Pulmonary congestion was less significant in patients with CC. The degree of LV of systolic and diastolic dysfunction and the RV diameter correlated with pulmonary congestion in both groups. The E/e' ratio was the hallmark of pulmonary congestion in both groups.