Myocarditis In Dogs Research Articles

Focused Cardiac Ultrasound Examination as a Tool for Diagnosis of Infective Endocarditis and Myocarditis in Dogs and Cats.

Simple SummaryInfective endocarditis and myocarditis are rarely diagnosed conditions with high mortality rates in dogs and cats. As their clinical signs are highly nonspecific, and advanced cardiological diagnostics are not always available in small animal clinics, both diseases seem to be underdiagnosed. Infective endocarditis affects mainly the mitral and aortic valves. In myocarditis, thickening of the left ventricle walls is usually observed; however, in some cases dilatation of the left ventricle lumen with thinning of the walls can be visible. In human medicine, basic cardiac ultrasound examination enables a quick initial diagnosis of these two conditions. Using this technique, we tentatively diagnosed 7 cases of myocarditis and/or infective endocarditis in dogs and cats, and these diagnoses were later confirmed by other methods. Because the initial diagnoses were made by a general practitioner after relatively short training, not by a cardiology specialist, we conclude that common use of this technique in small animal practices equipped with ultrasound device could increase the rate of diagnosis of these conditions, leading to earlier treatment initiation.Symptoms of infective endocarditis (IE) and myocarditis are usually nonspecific and include fever, apathy, and loss of appetite. This condition can lead to severe heart failure with ascites or/and fluid in the thoracic cavity or/and in the pericardial sac. We describe infective endocarditis and myocarditis in 3 dogs and 4 cats. In all animals, the initial diagnosis was performed on the basis of a focused cardiac ultrasound examination performed by a general practitioner after a training in this technique. The initial findings were confirmed by a board-certified specialist in veterinary cardiology. Post mortem positive microbiological results from valves were obtained in 4 of 7 patients. Methicillin-resistant Staphylococcus aureus was confirmed in 2 cases and Staphylococcus epidermidis was confirmed in 2 cases, one of which included Enterococcus sp. coinfection. Histopathological examination confirmed initial diagnosis in 5 of 7 animals. In the remaining 2 patients, the time elapsed from the onset of clinical symptoms to death was about 1 month and no active inflammation but massive fibrosis was found microscopically. This is, to our best knowledge, the first report of IE and myocarditis diagnosed in small animals using focused cardiac ultrasound examination. Therefore, we conclude that common usage of this technique by trained general veterinarians may increase the rate of diagnosed patients with these conditions.

Detection and molecular epidemiology of canine parvovirus type 2 (CPV-2) circulating in Jilin Province, Northeast China

Canine parvovirus (CPV) is highly contagious and can cause haemorrhagic enteritis and myocarditis in dogs. To understand the current epidemic situation of CPV in Jilin Province, China, a total of 44 fecal or intestinal tissue samples of pet dogs suspected of being infected with CPV from February 2018 to November 2019 in Changchun and Liaoyuan City, Jilin Province were collected.All of the 44 collected samples were tested positive to CPV-2 by a PCR assay. The sequencing and analyzing of complete VP2 genes showed that CPV-2c was the most prevalent variant (n = 31;70.4 %), followed by new-CPV-2a (n = 8;18.2 %), new-CPV-2b (n = 4; 9.1 %) and CPV-2 (n = 1; 2.3 %). Phylogenetic analysis revealed that the 31 CPV-2c strains in our study are closely related to local CPV-2c isolates in cluster I. The VP2 protein of the acquired CPV 2c strains all possessed the substitutions Ala5Gly, Phe267Tyr, Tyr324Ile, and Gln370Arg only one with a novel Arg481Lys mutation. These findings demonstrate that CPV-2c was the most prominent type of CPV circulating in Jilin in 2018–2019, clustered in a separate group that is far from the vaccine strains and suggest that further and extensive epidemiological investigation among pet dogs are warranted to provide information for usage and research of current vaccines.

Clinical presentation, cardiovascular findings, etiology, and outcome of myocarditis in dogs: 64 cases with presumptive antemortem diagnosis (26 confirmed postmortem) and 137 cases with postmortem diagnosis only (2004–2017)

IntroductionThis study describes presentation, cardiovascular abnormalities, etiology, and outcome of canine myocarditis in geographic areas not endemic for Trypanosoma or Leishmania. AnimalsSixty-four (presumed antemortem diagnosis) and 137 (postmortem diagnosis only) client-owned dogs at two tertiary care facilities were included. Materials and methodsMedical records of dogs with clinical or histopathological diagnosis of myocarditis were reviewed retrospectively. ResultsCommon examination findings in dogs with a presumed antemortem diagnosis included fever (21%) and heart murmur (19%). Median cardiac troponin I was 12.2 ng/mL (range: 0.2–808.0 ng/mL), and troponin exceeded 1.0 ng/mL in 26 of 29 (90%) dogs. Ventricular ectopy was the most common arrhythmia (54%), whereas decreased left ventricular systolic function was the most common echocardiographic abnormality (56%). An infectious etiology was diagnosed in 35 of 64 (55%) dogs. Confirmed infectious etiologies included bacterial sepsis (n = 9) or extension of endocarditis (3), toxoplasmosis or neosporosis (3), parvovirus (2), and one case each of bartonellosis, trypanosomiasis, leptospirosis, and dirofilariasis. Median survival time was 4 days (range: 0–828 days) for all dogs vs. 82 days for dogs who survived at least 2 weeks after diagnosis. Presence of pericardial effusion or azotemia was a significant predictor of non-survival. The most common inflammatory infiltrate on histopathology was neutrophilic (47%), and 20 of 137 (14.5%) dogs had concurrent bacterial endocarditis on postmortem. ConclusionsBacterial infection was the most common confirmed etiology of myocarditis in this study. Prognosis for canine myocarditis is guarded and similar to that reported for infective endocarditis. Criteria for the antemortem diagnosis of canine myocarditis are suggested.

Genetic characterization of canine parvovirus type 2c from domestic dogs in Korea.

Canine parvovirus type 2 (CPV‐2) is an aetiological agent that causes acute haemorrhagic enteritis and fatal myocarditis in dogs. Since CPV‐2 first emerged in the late 1970s, its rapid evolution has resulted in three antigenic variants: CPV‐2a, CPV‐2b and CPV‐2c. Here, we report, for the first time in Korea, two cases of CPV‐2c infection in two dogs with severe diarrhoea. The complete open reading frame (4,269nt) of CPV‐2, encoding both non‐structural (NS) and structural (VP) proteins, was sequenced. Based on the amino acid Gln present at residue 426 of the VP2 gene, these strains were typed as CPV‐2c, and were named Korea CPV‐2c_1 and Korea CPV‐2c_2. These strains shared 99.48% reciprocal nucleotide sequence identity and had the highest nucleotide identity (99.77%–99.34%) with Asian CPV strains isolated in China, Italy (found in a dog imported from Thailand), and Vietnam from 2013 to 2017. Phylogenetic analysis based on the non‐structural (NS1) and capsid (VP2) genes revealed that Korean CPV‐2c strains clustered closely to Asian CPV strains, and separately from strains isolated in Europe, South America and North America. Amino acid changes never reported before were observed in NS1 (Thr70Pro, Cys287Tyr), VP1 (Lys17Arg, Phe33Leu) and VP2 (Gln365His, Ala516Val). Additional observed mutations, including Phe267Tyr, Tyr324Ile and Gln370Arg, have been previously reported in the recent CPV‐2c strains with Asian origins. These results suggest that the Korean CPV‐2c strains were potentially introduced via neighbouring Asian countries.

Clinical-laboratory Manifestations of Myocarditis in Dogs

The leading clinical signs of myocarditis in dogs were the sudden development of signs of disease, refusal to eat, dyspnea at rest, rapid fatigue. At the diagnostic stage, the position of animals forced, lying, increased breathing speed up to 60-72 movements per minute, pale visible mucous membranes and conjunctiva, weak filling of pulse, rapid filling of capillaries, high blood pressure, increase in the number of leukocytes up to 25–27×109/l, SRS up to 15,4–17,4 mg/l, troponin up to 3,85–4,2 ng/ml. Electrocardiographic study established sinus or ectopic rhythm, heart rate 133– 198 oz/min, conductivity disturbance and deceleration. ECHOKG showed moderate expansion of the left ventricle, moderate expansion of the left atrium. Sealing of the mitral valve leaves, regurgitation on the mitral valve of the first degree. Left ventricular myocardium is inhomogeneous, wall echogenicity is increased. Fraction of contractility 16–18 %. After establishment of a dietary regime and correction of conditions of the maintenance, to dogs strictly with a twelve-hour interval twice a day are appointed vedmedin (0,25 mg/kg), sotalol (1,5 mg/kg), sinulox (20 mg/kg), mexidol-vet (1 table), verospheron (1 mg/kg). As a result of four-week monitoring of patients’ condition positive results were noted: lack of dyspnea, normalization of pulse rate and blood pressure, reduction of capillary filling rate up to 1 second, leukocyte concentration up to 12,6–15,7 ×109/l, SRS up to 1,3–1,4 mg/l, troponin up to 0,09–0,17 ng/ml. The electrocardiographic study showed a decrease in the height of teeth R and P, increase in the intervals P-Q and Q-T. The sinus rhythm is irregular. Echokg showed expansion of the left ventricle, moderate expansion of the left atrium. Sealing of mitral valve leaves, regurgitation on mitral valve of the first degree. Left ventricular myocardium is less heterogeneous, wall echogenicity is increased. Fraction of contractility 23–24 %. It is difficult to predict the outcome of the disease at this stage, as the age of dogs is 7–12 years, and in many respects the quality of life will be provided by their owners.

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Canine parvovirus (CPV) leads to an acute disease, characterized by hemorrhagic gastroenteritis, vomiting and myocarditis in dogs. The disease can affect dogs of any age but is fatal in pups. CPV has undergone genetic variations that have led to emergence of various CPV-2 antigenic variants such as 2a, 2b and 2c with replacement of the original CPV-2 circulating in the dog population. CPV genome is made up of 5.2 Kb nucleotides. Viral protein VP2 plays a very important role in determining antigenicity and host range specificity of CPV. The antigenicity as well as host range of CPV is determined by virus specific VP2 protein. That’s why the mutations that affect the VP2 gene are the main source of different antigenic variants. It spreads rapidly in the wild population of canines as well as domestic animals, infected feces serve as a main source of infection because the virus is shed in large quantity in the feces particularly 4 - 7 days post infection. The present review is focused on various

Suspected neospora-associated myocarditis in a dog

Neosporosis was diagnosed in an American Staffordshire Terrier with collapse and arrhythmia episodes by serological and cardiovascular examination. Clinical signs, diagnosis and treatment of Neospora caninum are described. The dog did not develop any neurological abnormality, which is the most common manifestation. Furthermore, the dog was also serologically positive for antibodies to Toxoplasma gondii and negative for Bartonella henselae and Borrelia burgdorferi. Serological diagnosis was achieved by indirect immunofluorescence. The arrhythmia, cardiac markers, biochemistry, complete blood count and clinical signs gradually improved following therapy with clindamycin and antiarrhythmic therapy. After 3 months of therapy Toxoplasma gondii titres persisted low but Neospora caninum titres changed to negative values. According to the veterinary literature and to the authors’ knowledge this was one of the few cases successfully treated for this condition. These observations demonstrated that neosporosis should be considered in the differential diagnosis of myocarditis in dogs and can be successfully treated by supportive therapy and clindamycin.

Clinical and histopathological features of myocarditis in dogs with visceral leishmaniasis

Visceral leishmaniasis (VL) is a cosmopolitan parasitic zoonosis that can promote myocarditis and heart rate changes in canine and human hosts. Thus, histopathological aspects of the myocardium and clinical, hematological, biochemical, radiological and electrocardiographic data were evaluated in a group of 36 dogs naturally infected with VL (VLG) and compared to data from 15 non-infected dogs (CG=Control Group). A prevalence of asymptomatic dogs was present in the CG (100%) and polysymptomatic dogs in the VLG (66%). In addition, two dogs in the VLG demonstrated systolic murmurs in the mitral valve region: one with a II/VI intensity and the other with a III/VI intensity. The mean values of RBC, hemoglobin and hematocrit were lower in dogs in VLG and were associated with higher values of total protein, total leukocytes, neutrophils, creatine kinase overall (CK) and the CK-MB fraction (CK-MB). The absence of radiographic changes was accompanied by a predominance of respiratory sinus arrhythmia associated with episodes of migratory pacemaker and sinus arrest in dogs in VLG (75%), sinus rhythm in dogs in CG (60%) and decreased P wave amplitude in VLG electrocardiography. Mononuclear cell infiltration was detected in the myocardium of 77,8% of dogs in GVL and classified primarily as mild multifocal lymphohistioplasmacytic. Amastigotes were detected in only one dog, which did not allow the association between myocarditis and parasitism, although the myocardial lesions that were found constitute irrefutable evidence of myocarditis in the VLG dogs, accompanied by lenient electrocardiographic changes compared to CG.

Predominance of canine parvovirus type 2b in dogs of Ulaanbaatar City

Canine parvovirus is a highly contagious virus that causes fatal disease acute hemorrhagic enteritis and myocarditis in dogs. The aim of this work is to detect canine parvovirus 2 (CPV-2) by standard polymerase chain reaction (PCR). Viral DNA was isolated from faecel samples of 36 puppies with suspicious symptoms for parvovirus infection and used as template in standard PCR. 23 samples wereof CPV-2b serotype, 9 samples of CPV-2a serotype but 4 samples were neither 2b and nor 2a. We used two different primer sets, one specific both serotypes CPV-2a and CPV-2b and one specific only for CPV-2b. This allowed us to differentiate serotypes from each other. The further extension of this work will be essential for the epidemiology, viral evolution and phylogenetic studies of the mongolian domestic canine, cats and wild carnivores.Mongolian Journal of Agricultural Sciences Vol.15(2) 2015; 71-74

Typing of Canine Parvovirus Strains Circulating in North-East China.

Canine parvovirus (CPV) is highly contagious and is a major cause of haemorrhagic enteritis and myocarditis in dogs. We investigated the genetic variation of emerging CPV strains by sequencing 64 CPV VP2 genes from 216 clinical samples of dogs from Heilongjiang, Jilin, Liaoning, Shandong and Hebei in 2014. Genetic analysis revealed that CPV-2b was predominant in Hebei and CPV-2a was predominant in the other four provinces. In addition, a CPV-2c strain has emerged in Shandong province. All samples had a Ser-Ala substitution at residue 297 and an Ile-Arg substitution at residue 324. Interestingly, in five separate canine samples, we found a mutation of Gln370 to Arg, until now detected only in isolates from pandas. The phylogenetic analysis showed clear distinctions between epidemic isolates and vaccine strains and between Chinese CPV-2c strains and CPV-2c strains found in other countries. Monitoring recent incidence of CPV strains enables evaluation and implementation of disease control strategies.

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

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.

Immunogenicity of a Canine Parvovirus 2 Capsid Antigen (VP2-S1) surface-expressed on Lactobacillus casei

Canine parvovirus (CPV2) is one of the most virulent virus causing acute hemorrhagic enteritis and myocarditis in dogs. Infection mainly caused by the ingestion of virus through the mucosal route. Therefore, induction of mucosal immunity is essential in prevention of Canine Parvovirus (CPV2) infection. For safe and effective delivery of viral antigens to the mucosal immune system, a novel surface antigen display system for lactic acid bacteria using the poly-γ-glutamic acid synthetase A protein (pgsA) of Bacillus subtilis as an anchoring matrix was applied in order to display CPV2 antigen on the surface of the recombinant L. casei. Recombinant fusion proteins comprised of pgsA and the capsid protein (VP2-S1) showed stable expression in Lactobacillus casei. Surface localization of the fusion protein was verified by cellular fractionation analyses. Oral and nasal inoculations of recombinant L. casei into mice resulted in high levels of serum immunoglobulin G (IgG) and mucosal IgA, as demonstrated by ELISA using recombinant VP2-S1 proteins. Mice receiving intranasal immunization mounted higher antibody response than those receiving oral immunization. These results indicate that mucosal immunization with recombinant L. casei expressing CPV2 VP2-S1 protein on its surface provides an effective means for elicitation of strong antibody responses against CPV 2 VP2-S1.

Plasma concentration of creatine kinase-MB isoenzyme in dogs with intestinal form of canine parvovirus-2 infection

Canine parvovirus (CPV) is the most dangerous and contagious virus that affects unprotected dogs. Two distinct parvoviruses are now known to infect dogs—the pathogenic CPV-2 and CPV-1 or the minute virus of canine. CPV-2, the causative agent of acute haemorrhagic enteritis and myocarditis in dogs, is one of the most important pathogenic viruses with high morbidity (100 %) and frequent mortality up to 10 % in adult dogs and 91 % in pups. The present investigation screened 45 clinical cases of canine gastroenteritis, and 10 dogs detected positive for canine parvovirus as confirmed by CPV-DNA amplification from feces using specific primers for CPV-2 by polymerase chain reaction were utilized for estimation of creatine kinase-MB isoenzyme (CK-MB) in plasma. Eight apparently healthy dogs were taken randomly to serve as the control group for CK-MB estimation in plasma. In conclusion, the findings of this study indicate that the CK-MB activity elevated with the severity of the disease in dogs infected with intestinal form of CPV-2.

Canine Parvovirus: Current Perspective

Canine parvovirus 2 (CPV-2) has been considered to be an important pathogen of domestic and wild canids and has spread worldwide since its emergence in 1978. It has been reported from Asia, Australia, New Zealand, the Americas and Europe. Two distinct parvoviruses are now known to infect dogs-the pathogenic CPV-2 and CPV-1 or the minute virus of canine (MVC). CPV-2, the causative agent of acute hemorrhagic enteritis and myocarditis in dogs, is one of the most important pathogenic viruses with high morbidity (100%) and frequent mortality up to 10% in adult dogs and 91% in pups. The disease condition has been complicated further due to emergence of a number of variants namely CPV-2a, CPV-2b and CPV-2c over the years and involvement of domestic and wild canines. There are a number of different serological and molecular tests available for prompt, specific and accurate diagnosis of the disease. Further, both live attenuated and inactivated vaccines are available to control the disease in animals. Besides, new generation vaccines namely recombinant vaccine, peptide vaccine and DNA vaccine are in different stages of development and offer hope for better management of the disease in canines. However, new generation vaccines have not been issued license to be used in the field condition. Again, the presence of maternal antibodies often interferes with the active immunization with live attenuated vaccine and there always exists a window of susceptibility in spite of following proper immunization regimen. Lastly, judicious use of the vaccines in pet dogs, stray dogs and wild canids keeping in mind the new variants of the CPV-2 along with the proper sanitation and disinfection practices must be implemented for the successful control the disease.

Molecular characterization and phylogenetic analysis of a canine parvovirus isolate in India

Canine parvovirus 2 (CPV-2) is the causative agent of acute hemorrhagic enteritis and myocarditis in dogs. In this study the nucleotide sequence of the VP1/VP2 gene of a CPV isolate from India was analyzed and the phylogenetic relationship with other CPV isolates was established. Out of 36 samples analyzed, 16 were found positive for CPV-2 by polymerase chain reaction (PCR). Among the 16 positive samples, five were inoculated in MDCK cells for isolation out of which one adapted successfully to the cell culture system. Phylogenetic analysis based on the nucleotide sequence of the VP-1/VP-2 gene revealed that the Indian isolate closely resembled a CPV-2b Italian strain, showing 98.4% nucleotide sequence homology indicating very little genetic divergence since it was first identified in 1978.

Polymerase chain reaction analysis for viruses in paraffin-embedded myocardium from dogs with dilated cardiomyopathy or myocarditis.

To perform polymerase chain reaction (PCR) analysis on paraffin-embedded myocardium from dogs with dilated cardiomyopathy (DCM) and dogs with myocarditis to screen for canine parvovirus, adenovirus types 1 and 2, and herpesvirus. Myocardial specimens from 18 dogs with an antemortem diagnosis of DCM and 9 dogs with a histopathologic diagnosis of myocarditis were evaluated. Paraffin-embedded myocardial specimens were screened for viral genome by PCR analysis. Positive-control specimens were developed from cell cultures as well as paraffin-embedded tissue specimens from dogs with clinical and histopathologic diagnoses of viral infection with canine parvovirus, adenovirus types 1 and 2, and herpesvirus. The histologic characteristics of all myocardial specimens were classified regarding extent, location, and type of inflammation and fibrosis. Canine adenovirus type 1 was amplified from 1 specimen from a dog with DCM. Canine parvovirus, adenovirus type 2, and herpesvirus were not amplified from any myocardial specimens. Histologic analysis of specimens from dogs with DCM revealed variable amounts of fibrosis; myocardial inflammation was observed in 1 affected dog. Histopathologic analysis of specimens from dogs with myocarditis disclosed variable degrees of inflammation and fibrosis. Viral agents canine parvovirus, adenovirus types 1 and 2, and herpesvirus are not commonly associated with DCM or active myocarditis in dogs. Additional studies evaluating for nucleic acid from viruses that less commonly affect dogs or different types of infectious agents may be warranted to gain insight into the cause of DCM and myocarditis in dogs.