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Background: Despite of a high disease burden, mainly in Latin America, Chagas disease (CD) is underdiagnosed and undertreated. Rapid diagnostic tests (RDTs) might improve the access to diagnosis. The aim of this study is to review the accuracy of commercially available RDTs used in field conditions for the diagnosis of chronic CD in populations at risk, in endemic and non-endemic countries. Methods/Principal findings: We undertook a comprehensive search of the following databases: PubMed, SCOPUS, LILACS (last up-date on the 01st July, 2017), without language or date limits. Non-electronic sources have been also searched. This review included clinical studies with cohort recruitment of individuals at risk of T. cruzi exposure, without age limits; adequate reference standards for the diagnosis of CD. We excluded case-control studies and those testing RDTs during acute CD. Data on test accuracies were pooled through a bivariate random-effects model. Only one index test was evaluated separately. Geographical area, commercial brand, disease prevalence, study size, and risk of bias were explored as possible source of heterogeneity. Values of sensitivity and specificity were computed to obtain summary positive/negative likelihood ratios, and summary diagnostic odds ratio. Ten studies were included on six different immunochromatographic RDTs. The pooled sensitivity and specificity of the RDTs resulted 96.6% (95% CI 91.3–98.7%) and 99.3% (95% CI 98.4–99.7%), respectively. Test accuracy was particularly good in endemic areas (98.07%/99.03% of sensitivity/specificity, respectively). One test (Stat-Pak) showed an overall sensitivity of 97% (95% CI 87.6–99.3) and specificity of 99.4% (95% CI 98.6–99.8). Conclusions/Significance: RDTs demonstrated to be sufficiently accurate to recommend their use for screening in endemic areas, even as stand-alone tests. This approach might increase the accessibility to the diagnosis. However, an additional confirmatory test in case of positive result remains a prudent approach. [ABSTRACT FROM AUTHOR]

Background: We evaluate the association between Trypanosoma cruzi infection and strongyloidiasis in a cohort of Latin American (LA) migrants screened for both infections in a non-endemic setting. Methodology: Case-control study including LA individuals who were systematically screened for T. cruzi infection and strongyloidiasis between January 2013 and April 2015. Individuals were included as cases if they had a positive serological result for Strongyloides stercoralis. Controls were randomly selected from the cohort of individuals screened for T. cruzi infection that tested negative for S. stercoralis serology. The association between T. cruzi infection and strongyloidiasis was evaluated by logistic regression models. Principal findings: During the study period, 361 individuals were screened for both infections. 52 (14.4%) individuals had a positive serological result for strongyloidiasis (cases) and 104 participants with negative results were randomly selected as controls. 76 (48.7%) indiviuals had a positive serological result for T. cruzi. Factors associated with a positive T. cruzi serology were Bolivian origin (94.7% vs 78.7%; p = 0.003), coming from a rural area (90.8% vs 68.7%; p = 0.001), having lived in an adobe house (88.2% vs 70%; p = 0.006) and a referred contact with triatomine bugs (86.7% vs 63.3%; p = 0.001). There were more patients with a positive S. stercoralis serology among those who were infected with T. cruzi (42.1% vs 25%; p = 0.023). Epidemiological variables were not associated with a positive strongyloidiasis serology. T. cruzi infection was more frequent among those with strongyloidiasis (61.5% vs 42.3%; p = 0.023). In multivariate analysis, T. cruzi infection was associated with a two-fold increase in the odds of strongyloidiasis (OR 2.23; 95% CI 1.07–4.64; p = 0.030). Conclusions: T. cruzi infection was associated with strongyloidiasis in LA migrants attending a tropical diseases unit even after adjusting for epidemiological variables. These findings should encourage physicians in non-endemic settings to implement a systematic screening for both infections in LA individuals. [ABSTRACT FROM AUTHOR]

Background: Bolivia has the highest prevalence of Chagas disease (CD) in the world (6.1%), with more than 607,186 people with Trypanosoma cruzi infection, most of them adults. In Bolivia CD has been declared a national priority. In 2009, the Chagas National Program (ChNP) had neither a protocol nor a clear directive for diagnosis and treatment of adults. Although programs had been implemented for congenital transmission and for acute cases, adults remained uncovered. Moreover, health professionals were not aware of treatment recommendations aimed at this population, and research on CD was limited; it was difficult to increase awareness of the disease, understand the challenges it presented, and adapt strategies to cope with it. Simultaneously, migratory flows that led Bolivian patients with CD to Spain and other European countries forced medical staff to look for solutions to an emerging problem. Intervention: In this context, thanks to a Spanish international cooperation collaboration, the Bolivian platform for the comprehensive care of adults with CD was created in 2009. Based on the establishment of a vertical care system under the umbrella of ChNP general guidelines, six centres specialized in CD management were established in different epidemiological contexts. A common database, standardized clinical forms, a and a protocolized attention to adults patients, together with training activities for health professionals were essential for the model success. With the collaboration and knowledge transfer activities between endemic and non-endemic countries, the platform aims to provide care, train health professionals, and create the basis for a future expansion to the National Health System of a proven model of care for adults with CD. Results: From 2010 to 2015, a total of 26,227 patients were attended by the Platform, 69% (18,316) were diagnosed with T. cruzi, 8,567 initiated anti-parasitic treatment, more than 1,616 health professionals were trained, and more than ten research projects developed. The project helped to increase the number of adults with CD diagnosed and treated, produce evidence-based clinical practice guidelines, and bring about changes in policy that will increase access to comprehensive care among adults with CD. The ChNP is now studying the Platform’s health care model to adapt and implement it nationwide. Conclusions: This strategy provides a solution to unmet demands in the care of patients with CD, improving access to diagnosis and treatment. Further scaling up of diagnosis and treatment will be based on the expansion of the model of care to the NHS structures. Its sustainability will be ensured as it will build on existing local resources in Bolivia. Still human trained resources are scarce and the high staff turnover in Bolivia is a limitation of the model. Nevertheless, in a preliminary two-years-experience of scaling up this model, this limitations have been locally solved together with the health local authorities. [ABSTRACT FROM AUTHOR]

The author discusses the trial for Benznidazole Evaluation for Interrupting Trypanosomiasis (BENEFIT) which evaluates the safety and efficacy of benznidazole for the treatment of patients with Chagasic cardiomyopathy. Topics discussed include the benefits of benznidazole for cardiac disease prevention, the polymerase chain reaction (PCR) conversion rates among Chagas disease patients in Brazil, and the role of comorbidities for its treatment.

Background: Digestive damage due to Chagas disease (CD) occurs in 15–20% of patients diagnosed as a result of peristaltic dysfunction in some endemic areas. The symptoms of chronic digestive CD are non-specific, and there are numerous confounders. Diagnosis of CD may easily be missed if symptoms are not evaluated by a well trained physician. Regular tests, as barium contrast examinations, probably lack the necessary sensitivity to detect early digestive damage. Methods: 71 individuals with T. cruzi infection (G1) and 18 without (G2) coming from Latin American countries were analyzed. They were asked for clinical and epidemiological data, changes in dietary habits, and history targeting digestive and cardiac CD symptoms. Serological tests for T. cruzi, barium swallow, barium enema, an urea breath test, and esophageal manometry were requested for all patients. Principal findings: G1 and G2 patients did not show differences in lifestyle and past history. Fifteen (21.1%) of G1 had digestive involvement. Following Rezende criteria, esophagopathy was observed in 8 patients in G1 (11.3%) and in none of those in G2. Manometry disorders were recorded in 34 G1 patients and in six in G2. Isolated hypotensive lower esophageal sphincter (LES) was found in sixteen G1 patients (23.9%) and four G2 patients (28.8%). Achalasia was observed in two G1 patients. Among G1 patients, ineffective esophageal motility was seen in six (five with symptoms), diffuse esophageal spasm in two (one with dysphagia and regurgitation), and nutcracker esophagus in three (all with symptoms). There were six patients with hypertonic upper esophageal sphincter (UES) among G1. Following Ximenes criteria, megacolon was found in ten G1 patients (13.9%), and in none of the G2 patients. Conclusions: The prevalence of digestive chronic CD in our series was 21.1%. Dysphagia is a non-pathognomonic symptom of CD, but a good marker of early esophageal involvement. Manometry could be a useful diagnostic test in selected cases, mainly in patients with T. cruzi infection and dysphagia in whose situation barium swallow does not evidence alterations. Constipation is a common but non-specific symptom that can be easily managed. Testing for CD is mandatory in a patient from Latin America with constipation or dysphagia, and if diagnosis is confirmed, megacolon and esophageal involvement should be investigated. [ABSTRACT FROM AUTHOR]

Immunosuppression, which has become an increasingly relevant clinical condition in the last 50 years, modifies the natural history of Trypanosoma cruzi infection in most patients with Chagas disease. The main goal in this setting is to prevent the consequences of reactivation of T. cruzi infection by close monitoring. We analyze the relationship between Chagas disease and three immunosuppressant conditions, including a description of clinical cases seen at our center, a brief review of the literature, and recommendations for the management of these patients based on our experience and on the data in the literature. T. cruzi infection is considered an opportunistic parasitic infection indicative of AIDS, and clinical manifestations of reactivation are more severe than in acute Chagas disease. Parasitemia is the most important defining feature of reactivation. Treatment with benznidazole and/or nifurtimox is strongly recommended in such cases. It seems reasonable to administer trypanocidal treatment only to asymptomatic immunosuppressed patients with detectable parasitemia, and/or patients with clinically defined reactivation. Specific treatment for Chagas disease does not appear to be related to a higher incidence of neoplasms, and a direct role of T. cruzi in the etiology of neoplastic disease has not been confirmed. Systemic immunosuppressive diseases or immunosuppressants can modify the natural course of T. cruzi infection. Immunosuppressive doses of corticosteroids have not been associated with higher rates of reactivation of Chagas disease. Despite a lack of evidence-based data, treatment with benznidazole or nifurtimox should be initiated before immunosuppression where possible to reduce the risk of reactivation. Timely antiparasitic treatment with benznidazole and nifurtimox (or with posaconazole in cases of therapeutic failure) has proven to be highly effective in preventing Chagas disease reactivation, even if such treatment has not been formally incorporated into management protocols for immunosuppressed patients. International consensus guidelines based on expert opinion would greatly contribute to standardizing the management of immunosuppressed patients with Chagas disease. [ABSTRACT FROM AUTHOR]

The article describes a case of pulmonary infiltrates and eosinophilia in a 25-year-old Spanish male who travelled to Senegal in September 2009 where he swam near the Dindefelo freshwater falls. The man reported fever, myalgia and dry cough after five weeks. His second blood sample analysis revealed eosinophilia, while his x-ray results showed patchy infiltrates in both lungs and pseudonodular lesions. His infection with Schistosoma species is claimed to be acquired by exposure to freshwater that contains cercariae.