Serial 'deep-sampling' PCR of fragmented DNA reveals the wide range of burden among chronically infected hosts and allows accurate monitoring of parasite load following treatment.

Infection with the protozoan parasite is generally well-controlled by host immune responses, but appears to be rarely eliminated. The resulting persistent, low-level infection results in cumulative tissue damage with the greatest impact generally in the heart in the form of chagasic cardiomyopathy. The relative success in immune control of infection usually averts acute phase death but has the negative consequence that the low-level presence of in hosts is challenging to detect unequivocally.

Viable Trypanosoma cruzi cultured from a dead Paratriatoma lecticularia (Hemiptera: Reduviidae) encountered in a large dog kennel environment in south Texas, USA.

Trypanosoma cruzi (Chagas, 1909) is a protozoan parasite transmitted by triatomine (Hemiptera: Reduviidae) insects and is the causative agent of Chagas disease. Oral transmission of the parasite occurs through consumption of contaminated food or infected triatomines and may depend on the degree to which T. cruzi survives in triatomine abdomens.

Double Outlet Right Atrium in an American Domestic Shorthair Cat.

• DORA should be considered in cases with radiographic evidence of LA enlargement. • TTE can diagnose DORA. • Cats with DORA may remain undiagnosed until adulthood.

Complex Tetralogy of Fallot in an Acyanotic Adult Dog.

• TOF with PA hypoplasia can be diagnosed in adult dogs. • MAPCAs were suspected on the basis of TTE detection of collateral vessels. • Acyanosis in this dog was attributed to multiple sources of pulmonary blood flow.

Positive clinical outcome using a modified dosing regimen of benznidazole in dogs at high risk for infection or acutely infected with Trypanosoma cruzi.

Trypanosoma cruzi infection in dogs can cause heart failure and sudden death with few treatment options available. A litter of 4 dogs living in a T cruzi endemic area were randomized to prophylaxis and nonprophylaxis groups as part of a study evaluating a modified benznidazole dosing regimen administered twice weekly to prevent T cruzi infection during a vector transmission season. The 2 dogs that received prophylaxis remained healthy without T cruzi infection or cardiac disease for >2 years.

Echocardiographic values and prevalence of cardiac abnormalities in clinically healthy adult Borzoi dogs.

Objective: To develop breed-specific echocardiographic values for normal Borzoi and to report the prevalence of structural cardiac abnormalities.

Animals: 146 clinically healthy, adult Borzoi dogs.

Methods: Cardiac auscultation and standard echocardiograms were performed.

Validation of a multiplex microsphere immunoassay for detection of antibodies to in dogs.

The vector-borne protozoan parasite causes Chagas disease in humans, dogs, and many other mammalian hosts. Canine Chagas disease is increasingly diagnosed in dogs of the southern United States where triatomine insect vectors occur, and there are limited veterinary testing options; only the indirect fluorescent antibody (IFA) test is offered at a single accredited diagnostic laboratory. We evaluated a multiplex microsphere immunoassay (MIA) for the detection of antibodies against in dogs and compared it with existing serologic methods to establish cutoff values and relative sensitivity and specificity.

Analytical validation, sample stability, and clinical evaluation of a new high-sensitivity cardiac troponin I immunoassay for use in dogs, with comparison to a previous ultrasensitive assay.

Cardiac troponin I (cTnI) is considered the gold standard biomarker for myocardial injury and shows a high degree of homology between humans and dogs. The ADVIA Centaur XP High-Sensitivity Troponin I (AC-cTnI-HS) assay has been validated for use in humans but not dogs. The study objectives were to analytically validate the AC-cTnI-HS assay in dogs, to assess correlation between the AC-cTnI-HS and a previous ADVIA Centaur TnI-Ultra (AC-cTnI-U) assay, to assess cTnI sample storage stability, and to clinically evaluate the AC-cTnI-HS assay in healthy dogs and dogs with cardiac disease.

A masked, placebo-controlled, randomized clinical trial evaluating safety and the effect on cardiac function of low-dose rapamycin in 17 healthy client-owned dogs.

Introduction: Geroscience studies of low-dose rapamycin in laboratory species have identified numerous benefits, including reversing age-related cardiac dysfunction. Cardiovascular benefits have been observed in dogs with 10 weeks of treatment, raising questions about possible benefits and adverse effects of long-term use of low-dose rapamycin. The objectives of this study were to assess the impact of 6 months of low-dose rapamycin on echocardiographic indices of cardiac function in healthy dogs and to document the occurrence of adverse events.

Cardiac Magnetic Resonance Imaging Detects Myocardial Abnormalities in Naturally Infected Dogs with Chronic Asymptomatic Chagas Disease.

infection causes inflammation and fibrosis, resulting in cardiac damage in dogs. The objectives of this study were to describe cardiac magnetic resonance imaging (CMR) in naturally infected dogs with chronic Chagas disease and the frequency of abnormalities for CMR and cardiac diagnostic tests. Ten asymptomatic, client-owned dogs seropositive for were prospectively enrolled in an observational study evaluating echocardiography, ECG (standard and ambulatory), cardiac troponin I (cTnI), and CMR.

Frequency Variation and Dose Modification of Benznidazole Administration for the Treatment of Trypanosoma cruzi Infection in Mice, Dogs, and Nonhuman Primates.

Trypanosoma cruzi naturally infects a broad range of mammalian species and frequently results in the pathology that has been most extensively characterized in human Chagas disease. Currently employed treatment regimens fail to achieve parasitological cure of T. cruzi infection in the majority of cases.

Collection of triatomines from sylvatic habitats by a Trypanosoma cruzi-infected scent detection dog in Texas, USA.

Background: Triatomine insects, vectors of the etiologic agent of Chagas disease (Trypanosoma cruzi), are challenging to locate in sylvatic habitats. Collection techniques used in the United States often rely on methods to intercept seasonally dispersing adults or on community scientists' encounters. Neither method is suited for detecting nest habitats likely to harbor triatomines, which is important for vector surveillance and control.

Frequency variation and dose modification of benznidazole administration for the treatment of infection in mice, dogs and non-human primates.

naturally infects a broad range of mammalian species and frequently results in the pathology that has been most extensively characterized in human Chagas disease. Currently employed treatment regimens fail to achieve parasitological cure of infection in the majority of cases. In this study, we have extended our previous investigations of more effective, higher dose, intermittent administration protocols using the FDA-approved drug benznidazole (BNZ), in experimentally infected mice and in naturally infected dogs and non-human primates (NHP).

A multicenter, retrospective study of cardiac disease in Borzoi dogs.

Borzoi are large, relatively uncommon sighthounds anecdotally reported to suffer from sudden death. This multicenter retrospective cohort study aimed to describe the sample of Borzoi presenting to veterinary cardiologists for evaluation, with records searched from 14 centers across a study period of up to 20 years. The study sample was comprised of 152 client-owned Borzoi, with dogs most commonly presenting for pre-breed screening in 87/152 (52%), followed by evaluation of an arrhythmia in 28/152 (18%).

Trypanosoma cruzi infection diagnosed in dogs in nonendemic areas and results from a survey suggest a need for increased Chagas disease awareness in North America.

Objective: To describe the clinical presentation and outcome in dogs diagnosed with Trypanosoma cruzi infection in nonendemic areas and to survey veterinary cardiologists in North America for Chagas disease awareness.

Animals: 12 client-owned dogs; 83 respondents from a veterinary cardiology listserv.

Procedures: A retrospective, multicenter medical records review to identify dogs diagnosed with American trypanosomiasis between December 2010 and December 2020.

Veterinary Chagas Disease (American Trypanosomiasis) in the United States.

Veterinary Chagas disease is a persistent threat to humans, dogs, and other wild or domestic mammals that live where infected triatomine "kissing bug" insect vectors occur across the Americas, including 28 states in the Southern United States. Animals infected with the Trypanosoma cruzi parasite may be asymptomatic or may develop myocarditis, heart failure, and sudden death. It is difficult to prevent animal contact with vectors because they are endemic in sylvatic environments and often disperse to domestic habitats.

Prophylactic low-dose, bi-weekly benznidazole treatment fails to prevent Trypanosoma cruzi infection in dogs under intense transmission pressure.

Trypanosoma cruzi naturally infects a wide variety of wild and domesticated mammals, in addition to humans. Depending on the infection dose and other factors, the acute infection can be life-threatening, and in all cases, the risk of chagasic heart disease is high in persistently infected hosts. Domestic, working, and semi-feral dogs in the Americas are at significant risk of T.

Asymptomatic Canine Degenerative Valve Disease: Diagnosis and Current and Future Therapies.

Degenerative valve disease (DVD) is the leading cause of heart disease and heart failure in the dog. The first consensus statement published in 2009 by the American College of Veterinary Internal Medicine was updated in 2019 and provides guidelines for the diagnosis and treatment of DVD. These updated guidelines recommend treatment with pimobendan in stage B2 DVD characterized by sufficient left heart enlargement.

Antiparasitic treatment with itraconazole and amiodarone in 2 dogs with severe, symptomatic Chagas cardiomyopathy.

Chagas cardiomyopathy, caused by the protozoal parasite Trypanosoma cruzi, is characterized by arrhythmias, myocardial damage, heart failure, and sudden death. We describe 2 dogs with severe, symptomatic Chagas cardiomyopathy characterized by myocardial dysfunction and electrocardiographic abnormalities that were managed with a combination of cardiac medications and antiparasitic treatment with itraconazole and amiodarone. Both dogs died suddenly within 6 months of diagnosis.

Prospective evaluation of complications associated with transesophageal echocardiography in dogs with congenital heart disease.

Background: Transesophageal echocardiography (TEE) is useful in the assessment and procedural monitoring of congenital heart disease (CHD) with a relatively low complication rate in humans.

Objectives: To evaluate the safety of TEE and report complications in dogs.

Animals: Forty client-owned dogs with CHD.

The Use of a Modified Script Concordance Test in Clinical Rounds to Foster and Assess Clinical Reasoning Skills.

The development of clinical reasoning skills is a high priority during clinical service, but an unpredictable case load and limited time for formal instruction makes it challenging for faculty to foster and assess students' individual clinical reasoning skills. We developed an assessment for learning activity that helps students build their clinical reasoning skills based on a modified version of the script concordance test (SCT). To modify the standard SCT, we simplified it by limiting students to a 3-point Likert scale instead of a 5-point scale and added a free-text box for students to provide justification for their answer.

Fatal Chagas myocarditis in government working dogs in the southern United States: Cross-reactivity and differential diagnoses in five cases across six months.

We describe the diagnostics surrounding the deaths of five working dogs over six-months to provide an enhanced clinical and diagnostic understanding of canine Chagas disease. Cases were five dogs with antibodies to Trypanosoma cruzi. Medical records were reviewed for diagnostic history.