Characterization of Latin American migrants at risk for Trypanosoma cruzi infection in a non-endemic setting. Insights into initial evaluation of cardiac and digestive involvement

Long-term follow-up of individuals with Chagas disease treated with posaconazole and benznidazole in a non-endemic region: the CHAGASAZOL cohort

OBJECTIVES

The CHAGASAZOL trial compared posaconazole and benznidazole for treating chronic Chagas disease. Posaconazole showed poor short-term efficacy by means of real-time polymearse chain reaction (qPCR) compared with benznidazole, but few studies have reported long-term follow-up using this tool. The aim of this study was to provide a more comprehensive analysis of the CHAGASAZOL cohort through 11 years of follow-up.

METHODS

This is a prospective observational cohort of individuals who were included in the CHAGASAZOL trial. Data were censored as of 31 December 2023. Subjects initially treated with posaconazole with a positive qPCR were offered re-treatment with benznidazole. All patients underwent clinical and electrocardiographic evaluations as well as a qPCR at a 6-month or 1-year interval. The primary objective was parasitological failure, defined as any positive qPCR in peripheral blood at any time during follow-up.

RESULTS

Seventy-two participants were enrolled (median follow-up: 71 months, range 1-147 months). At baseline, 59 (82%) were classified as indeterminate forms, 9 (12%) as cardiac, 2 (3%) as digestive, and 2 (3%) as mixed forms. Forty-eight participants received posaconazole, 45 completing at least 1 follow-up visit. Up to 43 of 45 (95%) presented a positive qPCR, and of them, 35 accepted to be retreated with benznidazole. Considering those treated with benznidazole (either initially or as a re-treatment), only 3 of 51 (6%) showed a positive qPCR. Four (5.5%) participants showed cardiac progression after 3-10 years of follow-up, with an incident rate of 0.94 events per 100 person-years. Two of them had received the complete benznidazole treatment, 1 was partially treated (17 days) and 1 was only treated with posaconazole before clinical progression.

DISCUSSION

Even if benznidazole showed parasitological efficacy, lifelong follow-up should be offered to individuals living with Chagas disease, as both parasitological failure and clinical progression can occur many years after diagnosis and treatment.

In vitro and in vivo evaluation of the trypanocidal activity of the acetone extract of lichen Usnea steineri and its chemical constituents

More than 2.5 billion people live in endemic areas for neglected tropical diseases caused by the protozoan Trypanosoma cruzi. Which establishes chronic infections and increases public health spending. Thus, this paper describes the chemical study of Usnea steineri acetone extract and evaluations of trypanocidal activity in vitro and in vivo. Four chemical constituents from the acetone extract have been isolated: usnic acid, diffractaic acid, galbinic acid, and norstictic acid. The acetone extract of U. steineri revealed an IC50 of 49.4 ± 1.5 µg/mL regarding the trypomastigote T. cruzi forms. The usnic acid revealed the biggest effectivity regarding the trypomastigote T. cruzi forms. The trypanocidal activity of the usnic acid regarding the amastigote forms revealed promising results, showing IC50 of 67.0 ± 3.8 µM. The in vivo evaluation with the usnic acid revealed a decreased parasitemia at 40 mg/kg. Therefore, the results obtained open the perspectives for future studies aiming at its pharmacological application.

New series of 3-pyridyl-1,3-thiazoles: In vitro and in vivo anti-Trypanosomatidae profile, in vitro and in silico mechanism of action approach

Trypanosomatidae diseases, such as Chagas disease and leishmaniasis, are caused by protozoan parasites of the Trypanosomatidae family, namely Trypanosoma cruzi and Leishmania species, respectively. There is an urgent need for new therapies. Both pyridine and thiazole rings are recognized as important scaffolds in medicinal chemistry. This study reports the synthesis of 3-pyridyl-1,3-thiazole derivatives (1-18) and their evaluation through in vitro and in vivo assays. In vitro tests were conducted against T. cruzi, L. amazonensis, and L. infantum, with cytotoxicity assessed using L929 fibroblasts and RAW 264.7 macrophages. Mode of action studies included in vitro assays and in silico simulations. Fourteen compounds exhibited trypanocidal activity with IC50 values ranging from 0.2 to 3.9 μM, outperforming benznidazole (4.2 μM). Compound 7 displayed an IC50 of 0.4 μM and a selectivity index of 530.8. However, the compounds were inactive in vivo assays at a dose of 100 mg/kg/day. Compounds 1, 7, 8, and 10 demonstrated trypanostatic effects, mitochondrial disruption, apoptosis induction, and parasite membrane damage. These compounds also modulated nitric oxide, IL-6, IL-10 and TNF production. In silico analysis indicated strong interactions with cruzain and favorable bioavailability, drug-likeness, and stability profiles. The leishmanicidal activity was negligible or absent. Despite promising in vitro trypanocidal activity, further structural optimization or formulation strategies are required to enhance oral stability and bioavailability, providing a foundation for the development of new therapeutic agents.

How do we classify organ involvement in Chagas disease? A systematic review of organ involvement since 1909, Highlighting the urgent need for a universal classification system in Chronic Chagas disease

Chagas disease (CD) is recognized as one of the 20 neglected tropical diseases by the World Health Organization (WHO), posing a significant global health challenge. The objective of this work was to conduct a systematic methodology review to explore the different classifications used to describe the presence and degree of organ involvement in patients with CD since the disease's description in 1909. We searched relevant electronic medical databases from their inception dates to July 2023. We also delved into historical variations and revisions of each classification, the necessary diagnostic methods, their prognostic value, and their uptake. Our study underscores the conspicuous absence of a universally accepted CD classification system for cardiac and digestive involvement, both in the context of clinical trials and within current clinical guidelines. This endeavour will facilitate cross-population comparisons if clinical manifestations and complementary test results are available for each patient, constituting a pivotal stride toward identifying precise prognoses and establishing a minimum data set requisite for a fitting CD classification, tailored to the test availability in both endemic and non-endemic regions.

Chagas cardiomyopathy in Boston, Massachusetts: Identifying disease and improving management after community and hospital-based screening

BACKGROUND

Limited data exist regarding cardiac manifestations of Chagas disease in migrants living in non-endemic regions.

METHODS

A retrospective cohort analysis of 109 patients with Chagas disease seen at Boston Medical Center (BMC) between January 2016 and January 2023 was performed. Patients were identified by screening and testing migrants from endemic regions at a community health center and BMC. Demographic, laboratory, and cardiac evaluation data were collected.

RESULTS

Mean age of the 109 patients was 43 years (range 19-76); 61% were female. 79% (86/109) were diagnosed with Chagas disease via screening and 21% (23/109) were tested given symptoms or electrocardiogram abnormalities. Common symptoms included palpitations (25%, 27/109) and chest pain (17%, 18/109); 52% (57/109) were asymptomatic. Right bundle branch block (19%, 19/102), T-wave changes (18%, 18/102), and left anterior fascicular block (11%, 11/102) were the most common electrocardiogram abnormalities; 51% (52/102) had normal electrocardiograms. Cardiomyopathy stage was ascertained in 94 of 109 patients: 51% (48/94) were indeterminate stage A and 49% (46/94) had cardiac structural disease (stages B1-D). Clinical findings that required clinical intervention or change in management were found in 23% (25/109), and included cardiomyopathy, apical hypokinesis/aneurysm, stroke, atrial or ventricular arrhythmias, and apical thrombus.

CONCLUSIONS

These data show high rates of cardiac complications in a cohort of migrants living with Chagas disease in a non-endemic setting. We demonstrate that Chagas disease diagnosis prompts cardiac evaluation which often identifies actionable cardiac disease and provides opportunities for prevention and treatment.

Practical diagnostic algorithms for Chagas disease: a focus on low resource settings

INTRODUCTION

Chagas disease, caused by parasite Trypanosoma cruzi, is the most important neglected tropical disease in the Americas. Two drugs are available for treatment, but access to them is challenging, in part due to complex diagnostic algorithms. These are stage-dependent, involve multiple tests, and are ill-adapted to the reality of vast areas where the disease is endemic. Molecular and serologic tools are used to detect acute and chronic infections, with the performance of the latter showing geographic differences. Breakthroughs in the development of new diagnostic tools include the validation of a loop-mediated isothermal amplification assay for acute infections (T. cruzi-LAMP), and the regional validation of several rapid diagnostic tests (RDTs) for chronic infection, which simplify testing in resource-limited settings. The literature search was carried out in the MEDLINE database until 1 August 2023.

AREAS COVERED

This review outlines existing algorithms, and proposes new ones focused on point-of-care testing.

EXPERT OPINION

Integrating point-of-care testing into existing diagnostic algorithms in certain endemic areas will increase access to timely diagnosis and treatment. However, additional research is needed to validate the use of these techniques across a wider geography, and to better understand the cost-effectiveness of their large-scale implementation.