Myocarditis in dogs: etiology, clinical and histopathological features (11 cases: 2007–2013)

Abstract

BackgroundMyocarditis is a disease caused by numerous etiological factors and characterized by a non-specific course. The only method allowing for precise characterization of inflammatory changes is the histopathological examination of heart muscle specimens. The study was conducted on heart muscle preparations from 11 dogs with ante-mortem diagnosis of cardiac disease. Animals presented with a poor response to an applied treatment or had suspected sudden cardiac death. The heart specimens were taken post-mortem, preserved and stained with haematoxylin and eosin. Subsequently, the presence and intensity of changes, i.e. inflammatory infiltration, the amount of connective tissue and features of cardiomyocyte degeneration were estimated. The specimens from dogs suspected of having a myocarditis of bacteriological etiology underwent additional bacteriological and immunohistochemical examination.ResultsThe examination revealed an inflammatory infiltration of variable intensity combined with the degenerative changes in all dogs. There were vegetative and abnormal cystic forms of Borrelia burgdorferi sensu lato in 6 dogs. A Staphylococcus aureus infection was confirmed in one dog and an acute coronary syndrome with neutrophil infiltration was revealed in another one.ConclusionsAlthough the clinical pattern in patients with myocarditis is diverse, the definitive morphological diagnosis is made based on the histopathological examination. This examination can lead to a better understanding of the pathogenesis of the disease. To the best of our knowledge, this is the first description of myocarditis combined with the presence of spore forms of Borrelia burgdorferi sensu lato in the heart specimens of dogs.Electronic supplementary materialThe online version of this article (doi:10.1186/s13620-014-0028-8) contains supplementary material, which is available to authorized users.

Tick-borne Diseases (Borreliosis, Anaplasmosis, Babesiosis) in German and Austrian Dogs: Status quo and Review of Distribution, Transmission, Clinical Findings, Diagnostics and Prophylaxis

“…In contrast to humans, no erythema migrans has been observed in dogs (Appel et al 1993), but synovial lesions were significant in infected dogs in all canine experimental studies (Appel et al 1993;Summers et al 2005;Susta et al 2012;Wagner et al 2012). After natural infection, lameness has been described in <5 % of dogs (Levy and Magnarelli 1992;McKenna et al 1995;Hovius et al 2000;Chou et al 2006;Littman et al 2006), less than 1 -2 % show kidney disease (Dambach et al 1997;Chou et al 2006;Littman 2013), and the very rare cases with cardiac (Chou et al 2006;Agudelo et al 2011;Janus et al 2014) and neurological (McKenna et al 1995) involvement are assumed rather than documented. No association was found between exposure to either Borrelia species (or A. phagocytophilum) and neurological signs or inflammatory CNS disease in retrospective and prospective studies (Jäderlund et al 2007(Jäderlund et al , 2009, which have been subsequently confirmed by experimental infection (Krimer et al 2011).…”

Cardiac and Metabolic Variables in Obese Dogs

“…All dogs were fasted overnight and determined to be euthyroid with no evidence of systemic illness on routine laboratory diagnostics including CBC, serum biochemical profile, urinalysis, and serum total T4 concentration. Past infectious diseases, such as ehrlichiosis and Lyme disease, and immune‐mediated disease were not evaluated but dogs with a history of infectious or immune‐mediated disease were excluded . Body condition was assessed by a validated 9‐point scale in which ideal body condition was defined as a body condition score (BCS) of 4 or 5 .…”

“…Past infectious diseases, such as ehrlichiosis and Lyme disease, and immune-mediated disease were not evaluated but dogs with a history of infectious or immune-mediated disease were excluded. 32 Body condition was assessed by a validated 9-point scale in which ideal body condition was defined as a body condition score (BCS) of 4 or 5. 33,34 Dogs with normal BCSs of 4 and 5 were allocated to the ideal weight group and dogs with BCSs of 6, 7, 8, and 9 were allocated to the obese group.…”

Bartonella-associated inflammatory cardiomyopathy in a dog

“…Staphylococcus, Streptococcus, Citrobacter, Bartonella, Borrelia), fungal agents (i.e. Coccidioides, Cryptococcus, Aspergillus), helminthes (Toxocara), and non-infectious factors such as autoimmune reactions, toxins, trauma, heat stroke, and hemodynamic shock [6].…”

“…Through PCR analysis, we tested the most common etiologic agents reported to cause myocarditis in dogs [6] and all viruses resulted to be negative. Others rare non-viral agents causing myocarditis in dogs could not be tested with molecular biology due to financial constrains.…”