Estratificación del riesgo en la enfermedad de Chagas

Acute Chagas Disease Presenting as Preseptal Cellulitis

Chagas disease, also known as American trypanosomiasis, is caused by Trypanosoma cruzi, a parasite transmitted by hematophagous triatomine insects (subfamily Triatominae) belonging to the Reduviidae family, order Hemiptera. Infection occurs through contact with the feces of the infected vector at the site of its bite or on intact mucosa. [Pediatr Ann. 2023;52(10):e394-e397.].

Trypanosoma cruzi: A review of biological and methodological factors in Mexican strains

Trypanosoma cruzi, responsible for Chagas disease, is a serious public health problem in Latin America with eight million people infected in the world. Clinical manifestations observed in humans due to T. cruzi infection are largely associated with the wide biological and genetic heterogeneity of the parasite. This review presents an overview of the parasitological aspects of various strains of T. cruzi isolated mainly in Mexico, as well as an analysis of the methodological processes used to determine their virulence that could be influencing their biological characterization. We emphasize the importance of using uniform protocols to study T. cruzi virulence, taking into account factors related to: strain (i.e. developmental stage, lineage, biological origin, genetic variability), animal model used (i.e. role of hormones, host immune response, age) and methodology (i.e. inoculum size, inoculation route, and laboratory conditions used during strain maintenance). These uniform protocols will then allow proposing elements for understanding clinical evolution and management of the disease, for providing adequate treatment, and for developing tools for future vaccines against Chagas disease.

[Diagnostic performance of surface electrocardiogram in early detection of chagasic cardiomyopathy]

BARCKGROUND AND OBJECTIVE

Contrast-enhanced cardiac magnetic resonance imaging (CMR) allows early detection of myocardial involvement by Trypanosoma cruzi infection. The aim of our study was to assess the diagnostic performance of the surface electrocardiogram (ECG) in the early detection of Chagas' cardiomyopathy (CCM) compared with CMR.

METHODS

We included 43 asymptomatic patients (30 women, 42 ± 9.8 years), diagnosed of Chagas disease. The sample was divided into 2 groups according to the presence (n=17) or absence (n=26) of electrocardiographic abnormalities. All patients underwent CMR and late gadolinium enhancement (LGE) was used as a marker of early myocardial involvement.

RESULTS

Six (14%) patients had a LGE significantly higher in the group who had electrocardiographic abnormalities (29 vs. 4%, P<.05). With CMR as the method of reference, the ECG had a sensitivity of 83% and a negative predictive value of 96% to detect CCM.

CONCLUSION

ECG is a useful, inexpensive and globally available tool for the screening of CCM in asymptomatic patients but with proven myocardial involvement in CMR.

β1-selective adrenoceptor antagonists increase plasma levels of anti-p2β antibodies and decrease cardiac involvement in chronic progressive Chagas heart disease

BACKGROUND

Studies indicate that antibodies cross-reacting with cardiac β1 adrenergic receptors are likely to play a role in the development of chronic Chagas heart disease (CCHD). In parallel, clinical trials have shown that β1 antagonist drugs exert beneficial effects in the prognosis of patients with CCHD. In a group of patients with CCHD undergoing therapy with β1-blockers, we have now evaluated the levels of anti-p2β antibodies and the severity of CCHD.

METHODS

We performed a cross-sectional study in Trypanosoma cruzi seropositive patients categorized according to a standard CCHD classification. All individuals were subjected to a complete clinical examination.

RESULTS

There was no association between CCHD stages, electrocardiographic conduction disturbances, and echocardiogram pathological signs with the levels of autoantibodies. However, when patients were analyzed according to selective cardio-β1-blocker therapy, those receiving treatment had higher levels of anti-p2β. Patients from CCHD stage III treated with combined therapy of cardio-β1-selective blockers, enalapril, and statins, presented decreased cardiac involvement and lower score of risk of mortality than individuals from the same group who were not treated.

CONCLUSIONS

Our results suggest that selective cardio-β1-blockers might modify the autoantibody anti-p2β levels, and that combined therapy in patients with stage III CCHD might be associated with lower cardiac involvement and risk score of mortality in patients with heart failure. Longitudinal studies will help to ascertain the proper role of β1-blockers in the immunopathological processes underlying chronic Chagas disease.

Assessment of cross-reactive host-pathogen antibodies in patients with different stages of chronic Chagas disease

INTRODUCTION AND OBJECTIVES

Trypanosoma cruzi infection has been shown to induce humoral autoimmune responses against host antigens tissues. Particularly, antibodies cross-reacting with myocardial antigens may play a role in the development of the severe forms of chronic Chagas disease. The aim of this study was to determine the association between clinical stage of the disease and the presence of autoantibodies in patients with chronic Chagasic disease.

METHODS

We performed a cross-sectional study in T. cruzi-seropositive patients divided into 3 groups according to the classic classification of chronic Chagas heart of Storino et al. All participants underwent complete clinical examination and their sera were used to measure autoantibody levels.

RESULTS

All patients had detectable levels of anti-p2β and anti-B13 autoantibodies but none had anti-Na-K-ATPase antibodies. No association was observed between electrocardiographic conduction disturbances and autoantibody levels. Patients with chronic Chagas disease stage III had the highest levels of anti-B13 antibodies and a high risk of mortality score, showing a clear association between disease stage and this score.

CONCLUSIONS

Anti-B13 antibodies were significantly higher in chronic Chagas disease stage III patients, suggesting that these antibodies may be involved in disease progression and that they might be a useful marker of poor prognosis in terms of heart compromise. Our results also reveal an important correlation between the level of anti-B13 autoantibodies and symptomatic heart failure and/or dilated cardiomyopathy.