Bartonella-associated inflammatory cardiomyopathy in a dog

Area of Science:

• Veterinary Cardiology
• Infectious Diseases in Animals
• Canine Pathology

Background:

• Dilated cardiomyopathy is a common cause of congestive heart failure in dogs.
• Bacterial infections can potentially affect cardiac function, but are less commonly diagnosed as a primary cause of cardiomyopathy.

Observation:

• A 6-year-old male dog presented with acute dyspnea, cough, cachexia, and severe depression.
• Electrocardiogram showed left bundle branch block and frequent ventricular arrhythmias.
• Thoracic radiographs revealed cardiomegaly and pulmonary edema; echocardiography showed dilated cardiomyopathy with segmental dyskinesis.

Findings:

• Despite treatment for congestive heart failure, the dog experienced sudden death.
• Histopathology revealed myocyte hypertrophy, fibrosis, and lymphoplasmocytic infiltrates.
• Immunohistochemistry confirmed T-lymphocyte infiltration (CD3) and B-lymphocyte presence (CD79).
• Polymerase chain reaction detected Bartonella spp. DNA.

Implications:

• This case highlights bacterial inflammatory cardiomyopathy as a potential cause of sudden cardiac death in dogs.
• Bartonella infection should be considered in the differential diagnosis of canine cardiomyopathy, especially in cases with inflammatory infiltrates.
• Further research is warranted to understand the pathogenesis and prevalence of Bartonella-associated cardiomyopathy in canines.