Browsing by Autor "Caryn Bern"

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Abstract 16978: Use of 2-D Speckle Tracking Strain to Predict Onset of Cardiomyopathy in Chagas Disease
(Lippincott Williams & Wilkins, 2018) Monica Miranda Schaeubinger; Sithu Win; Lola Camila Telleria; Freddy Tinajeros; Jorge Flores; Paula P. Carballo-Jimenez; Caryn Bern; Ronald Gustavo Durán Saucedo; Robert H. Gilman; Monica Mukherjee
Introduction: Chagas disease is a major cause of morbidity in Latin America where it affects approximately 8 million people, with highest prevalence in Bolivia. An estimated 20-30% of those infected develop Chagas cardiomyopathy (CC) and clinical heart failure. There is currently a lack of reliable predictors of CC, hindering early identification and treatment of patients at highest risk of progression. Methods: This prospective observational study was conducted at the Hospital San Juan de Dios in Santa Cruz, Bolivia. Between 2016 and 2018, participants with Chagas disease underwent a focused history and physical exam, 12-lead ECG and echocardiogram at baseline and at 1-year follow-up. Participants were assigned cardiac disease severity stages according to ECG findings and systolic function as done by Okamoto et al. Those classified as stage A or B at baseline were selected from the overall cohort, and considered to have developed cardiomyopathy (stage C or D) by structural abnormalities on their follow-up echo. Echocardiograms were analyzed for peak averaged and regional left ventricular global longitudinal systolic strain (GLS) using TomTec Image-Arena software. Baseline GLS was compared between those who progressed and those who did not using two-sample t-tests. Results: Of the 113 participants with stage A or B at baseline, 10 had progressed to stage C or D at follow-up 1 year later. Mean age was similar in the two groups, however those who progressed were more likely to be male (see table). At baseline, mean LVEF was lower and peak GLS was less negative among those who progressed compared to those who did not. These differences were similar at the follow-up visit. Conclusion: Mild abnormalities in GLS identify patients with Chagas disease with a higher risk of developing cardiomyopathy within 1 year. Screening for these changes may provide a non-invasive and cost-effective approach to identify patients who could benefit from timely management.
Chagas disease in the Bolivian Chaco: Persistent transmission indicated by childhood seroscreening study
(Elsevier BV, 2019) Thomas S. Hopkins; Raquel Gonçalves; Janet Mamani; Orin Courtenay; Caryn Bern
Early identification of patients with Chagas disease at risk of developing cardiomyopathy using 2-D speckle tracking strain
(Elsevier BV, 2022) Sithu Win; Monica Miranda‐Schaeubinger; Ronald Gustavo Durán Saucedo; Paula P. Carballo-Jimenez; Jorge Flores; Brandon N. Mercado-Saavedra; Lola Camila Telleria; Anne G. Raafs; Manuela Verástegui; Caryn Bern
Baseline LV GLS in participants with CCC stage A or B was predictive of progression within 1-year and may guide timing of clinical follow-up and promote early detection or treatment.
Genetic association study of NLRP1, CARD, and CASP1 inflammasome genes with chronic Chagas cardiomyopathy among Trypanosoma cruzi seropositive patients in Bolivia
(Public Library of Science, 2018) Steven J. Clipman; Josephine Henderson-Frost; Katherine Y. Fu; Caryn Bern; Jorge Flores; Robert H. Gilman
About 20-30% of people infected with Chagas disease present with chronic Chagas cardiomyopathy (CCC), the most serious and frequent manifestation of the disease, while others remain asymptomatic and often do not experience Chagas-specific mortality. It is not currently well understood what causes these differential disease outcomes, but a genetic predisposition within the host could play an important role. This study examined variants in the NLRP1, CARD, and CASP1 inflammasome genes among 62 T. cruzi seropositive patients from Bolivia (38 cases with CCC and 24 asymptomatic controls) to uncover associations with CCC. All subjects underwent a complete medical examination including electrocardiogram (EKG) and echocardiogram. After genotype calling and quality control filtering with exclusion of 3 cases and 3 controls, association analysis was performed across 76 directly genotyped SNPs in NLRP1, CARD, and CASP1 genes, adjusting for age, sex, and population stratification. One SNP (rs11651270; Bonferroni-corrected p = 0.036) corresponding to a missense mutation in NLPR1 was found to be significant after adjustment for multiple testing, and a suggestive association was seen in CARD11 (rs6953573; Bonferroni-corrected p = 0.060). Although limited by sample size, the study results suggest variations in the inflammasome, particularly in NLRP1 and CARD11, may be associated with CCC.
Improved Completion Rates and Characterization of Drug Reactions with an Intensive Chagas Disease Treatment Program in Rural Bolivia
(Public Library of Science, 2013) Jeffrey A. Tornheim; Daniel Franz Lozano Beltrán; Robert H. Gilman; Mario Castellon; Marco Solano; Walter Sullca; Faustino Torrico; Caryn Bern
Intensive management improved completion and identified more ADEs, but did not reduce moderate or severe ADEs. Risk of dermatologic ADEs cannot be reduced by selecting younger adults or monitoring only during the first few weeks of treatment. Pill counts and phone-based encounters are reliable tools for treatment programming in rural Bolivia.
Knowledge, Attitudes, and Practices toward Chagas Disease: A Cross-Sectional Survey of Bolivians in the Gran Chaco and Latin American Migrants in London
(American Society of Tropical Medicine and Hygiene, 2025) María José Hernández; Natalie Elkheir; Temitope Fisayo; Raquel Gonçalves; Edson Grover Sañer Liendo; Caryn Bern; David Moore
Understanding the at-risk population's perception of Chagas disease is essential for its effective prevention and control. A cross-sectional survey of knowledge, attitudes, and practices toward Chagas disease was conducted with Bolivians in a highly endemic region of Bolivia and Latin American migrants in London. In total, 175 participants completed the survey: 100 Bolivians in a highly endemic village in Santa Cruz, Bolivia and 75 Latin American migrants in London (of whom 31 were from Bolivia). All participants from the endemic village and all Bolivian migrants in London knew of Chagas disease, whereas only 25% of other Latin American migrants had heard of it (P <0.001). In London, Bolivians had more knowledge of Chagas disease than those from other Chagas-endemic countries. In Bolivia only, better understanding of Chagas disease was associated with educational attainment. Only 4% of participants overall were aware of the risk of vertical transmission. Few Latin American migrants in London had previously been tested for Chagas disease, and most were not aware of how to access testing. Migration and level of endemicity may shape individuals' understanding of as well as attitudes and practices toward Chagas disease. A better understanding of these factors can guide effective prevention and control program development in both endemic and non-endemic settings.
Prevalence of Chagas Heart Disease in a Region Endemic for <i>Trypanosoma Cruzi</i>: Evidence From a Central Bolivian Community
(Elsevier BV, 2015) Jessica E. Yager; Daniel Franz Lozano Beltrán; Faustino Torrico; Robert H. Gilman; Caryn Bern
Though almost one-third of adults in the community were seropositive for T. cruzi infection, few had evidence of Chagas heart disease.
Toxicological, Enzymatic, and Molecular Assessment of the Insecticide Susceptibility Profile of<i>Triatoma infestans</i>(Hemiptera: Reduviidae, Triatominae) Populations From Rural Communities of Santa Cruz, Bolivia
(Oxford University Press, 2016) Pablo Luis Santo‐Orihuela; Claudia Vassena; Guillermo Carvajal; Eva H. Clark; Silvio Menacho; Ricardo Bozo; Robert H. Gilman; Caryn Bern; Paula L. Marcet
A wide range of insecticide resistance profiles has been reported across Bolivian domestic and sylvatic populations of Triatoma infestans (Klug, 1834) (Hemiptera, Reduviidae), including some with levels proven to be a threat for vector control. In this work, the insecticide profile of domestic T. infestans was studied with standardized toxicological bioassays, in an area that has not undergone consistent vector control. F1 first-instar nymphs hatched in laboratory from bugs captured in three communities from the Santa Cruz Department were evaluated with different insecticides. Moreover, the enzymatic activity of esterases and cytochrome P450 monooxygenases was measured in individual insects to evaluate the possible mechanism of metabolic resistance to pyrethroids. In addition, the DNA sequence of sodium channel gene (kdr) was screened for two point mutations associated with pyrethroid resistance previously reported in T. infestans.All populations showed reduced susceptibility to deltamethrin and α-cypermethrin, albeit the RR50 values varied significantly among them. Increased P450 monooxygenases and permethrate esterases suggest the contribution, as detoxifying mechanisms, to the observed resistance to deltamethrin in all studied populations. No individuals presented either mutation associated to resistance in the kdr gene. The level of susceptibility to α-cypermethrin, the insecticide used by the local vector control program, falls within an acceptable range to continue its use in these populations. However, the observed RR50 values evidence the possibility of selection for resistance to pyrethroids, especially to deltamethrin. Consequently, the use of pyrethroid insecticides should be closely monitored in these communities, which should be kept under entomological surveillance and sustained interventions.