Chagas' disease and kidney donation

Oral Route Driven Acute Trypanosoma cruzi Infection Unravels an IL-6 Dependent Hemostatic Derangement

Oral transmission of Trypanosoma cruzi, the etiologic agent of Chagas disease, is presently the most important route of infection in Brazilian Amazon. Other South American countries have also reported outbreaks of acute Chagas disease associated with food consumption. A conspicuous feature of this route of transmission is presenting symptoms such as facial and lower limbs edema, in some cases bleeding manifestations and risk of thromboembolism are evident. Notwithstanding, studies that address this route of infection are largely lacking regarding its pathogenesis and, more specifically, the crosstalk between immune and hemostatic systems. Here, BALB/c mice were orally infected with metacyclic trypomastigotes of T. cruzi Tulahuén strain and used to evaluate the cytokine response, primary and secondary hemostasis during acute T. cruzi infection. When compared with control uninfected animals, orally infected mice presented higher pro-inflammatory cytokine (TNF-α, IFN-γ, and IL-6) serum levels. The highest concentrations were obtained concomitantly to the increase of parasitemia, between 14 and 28 days post-infection (dpi). Blood counts in the oral infected group revealed concomitant leukocytosis and thrombocytopenia, the latter resulting in increased bleeding at 21 dpi. Hematological changes paralleled with prolonged activated partial thromboplastin time, Factor VIII consumption and increased D-dimer levels, suggest that oral T. cruzi infection relies on disseminated intravascular coagulation. Remarkably, blockade of the IL-6 receptor blunted hematological abnormalities, revealing a critical role of IL-6 in the course of oral infection. These results unravel that acute T. cruzi oral infection results in significant alterations in the hemostatic system and indicates the relevance of the crosstalk between inflammation and hemostasis in this parasitic disease.

Lower urinary tract dysfunction in chronic Chagas disease: clinical and urodynamic presentation

Purpose

To describe and give an estimation of the prevalence of urinary disorders in chronic Chagas disease, since most clinical research has been centered on the description of the cardiac and digestive forms.

Methods

To explore this topic, a cross-sectional study was conducted in 137 Bolivian adults of both sexes suffering from symptomatic chronic Chagas disease. All patients presenting confirmed chagasic cardiomyopathy, megacolon or both underwent a urologic symptom questionnaire, uroflowmetry, urinary tract ultrasonography and a creatinine assay. When urinary abnormality was detected, a complete urodynamic study was proposed including cystometry, pressure-flow studies and urethral pressure profile.

Results

Out of all study patients, 35 (26%) had a Chagas cardiomyopathy, 81 (59%) a megacolon, and 21 (15%) a megacolon associated with cardiomyopathy. In all, 63% presented urinary disorders defined by IPSS > 7 and/or ICIQ SF > 1. Among them, 62% were incontinent, mainly by bladder overactivity, and 45% presented grade 2 or 3 renal insufficiency. Of 49 patients, the urodynamic study identified 34 patients with detrusor overactivity (69%), mostly in those with Chagas megacolon. Median bladder functional capacity, urethral closure pressure and bladder compliance had normal values. Moreover, 36% of these patients presented moderate hypocontractility, without significant post-void residual.

Conclusions

This study evidenced lower urinary tract dysfunction in a majority of chronic chagasic patients; those presenting megacolon were more likely to suffer from urinary incontinence. These results strongly suggest including routine urological clinical investigation in chronic Chagas patients, as urinary incontinence due to overactive bladder is frequently observed in this population.

Oral Outbreak of Chagas Disease in Santa Catarina, Brazil: Experimental Evaluation of a Patient's Strain

Chagas disease is a worldwide public health problem. Although the vectorial transmission of Chagas disease has been controlled in Brazil there are other ways of transmission, such as the ingestion of T. cruzi contaminated food, which ensures the continuation of this zoonosis. Here, we demonstrate the influence of the inoculation route on the establishment and development of the SC2005 T. cruzi strain infection in mice. Groups of Swiss mice were infected intragastrically (IG) or intraperitoneally (IP) with the T. cruzi SC2005 strain derived from an outbreak of oral Chagas disease. The results revealed that 100% of IP infected mice showed parasitemia, while just 36% of IG infected showed the presence of the parasite in blood. The parasitemia peaks were later and less intense in the IG infected mice. Mortality of the IP infected animals was more intense and earlier when compared to the IG infected mice. In the IP infected mice leucopenia occurred in the early infection followed by leucocytosis, correlating positively with the increase of the parasites. However, in the IG infected mice only an increase in monocytes was observed, which was positively correlated with the increase of the parasites. Histopathological analyses revealed a myotropic pattern of the SC2005 strain with the presence of inflammatory infiltrates and parasites in different organs of the animals infected by both routes as well as fibrosis foci and collagen redistribution. The flow cytometric analysis demonstrated a fluctuation of the T lymphocyte population in the blood, spleen and mesenteric lymph nodes of the infected animals. T. cruzi DNA associated with the presence of inflammatory infiltrates was detected by PCR in the esophagus, stomach and intestine of all infected mice. These findings are important for the understanding of the pathogenesis of T. cruzi infection by both inoculation routes.