Fatal case of endocarditis associated with Bartonella henselae type I infection in a domestic cat

A Review of Bartonella Infections in California-Implications for Public and Veterinary Health

Bartonella are vector-transmitted, intracellular bacteria that infect a wide variety of blood-feeding arthropods and their vertebrate hosts. In California, more than 13 species of Bartonella have been described from companion animals, livestock, and wildlife, of which four have been associated with human disease. Infections in humans cause a range of symptoms from relatively mild to severe, especially in immunocompromised individuals. Exposure to infected domestic animals and wildlife, and their ectoparasites, may increase the risk of cross-species transmission. The objective of this review was to compile and summarize published materials on human and animal Bartonella infections in California. Medical and veterinary case reports of bartonellosis were highlighted in an effort to increase the awareness of this poorly understood and potentially under-recognized disease among healthcare professionals and veterinarians.

Treatment of a cat with presumed Bartonella henselae-associated immune-mediated hemolytic anemia, fever, and lymphadenitis

A 2.5‐year‐old castrated male cat presented with fever and marked generalized lymphadenopathy of 4‐months duration, despite treatment with amoxicillin‐clavulanate/marbofloxacin. Abnormalities were not detected on complete blood count, serum chemistry, and FIV/FeLV test apart from a borderline, non‐regenerative anemia. Peripheral lymph node fine needle aspirations revealed a marked increase in the percentage of intermediate‐ and lymphoblastic‐lymphocytes in addition to reactive macrophages. Three weeks after presentation, the cat developed a severe, regenerative, immune‐mediated hemolytic anemia (IMHA) which responded to immunosuppressive therapy. Fever and lymphadenopathy persisted. Peripheral lymph nodes tested positive for Bartonella henselae DNA in real‐time PCR assay and sequencing. Treatment with pradofloxacin and doxycycline resulted in resolution of clinical signs, and negative PCR tests. Despite its reported low pathogenicity, B. henselae infection should also be considered in cats with protracted unexplained fever, lymphadenitis, and IMHA. Furthermore, a combination of pradofloxacin and doxycycline might be considered in cats with bartonellosis given its apparent clinical efficacy.

Prospective serological and molecular cross-sectional study focusing on Bartonella and other blood-borne organisms in cats from Catalonia (Spain)

Background

There is limited clinical or epidemiological knowledge regarding Bartonella infection in cats, and no serological studies have compared the presence of antibodies against different Bartonella species. Moreover, there are limited feline Bartonella studies investigating co-infections with other vector-borne pathogens and the associated risk factors. Therefore, the objective of this study was to investigate Bartonella spp. infections and co-infections with other pathogens in cats from Barcelona (Spain) based on serological and/or molecular techniques and to determine associated risk factors.

Methods

We studied colony and owned cats (n = 135). Sera were tested for Bartonella henselae-, Bartonella quintana-, and Bartonella koehlerae-specific antibodies using endpoint in-house immunofluorescence antibody assays. Bartonella real-time PCR (qPCR) and conventional PCR (cPCR) were performed. In addition, cPCR followed by DNA sequencing was performed for other pathogenic organisms (Anaplasma, Babesia, Cytauxzoon, Ehrlichia, Hepatozoon, hemotropic Mycoplasma, and Theileria spp.).

Results

From 135 cats studied, 80.7% were seroreactive against at least one Bartonella species. Bartonella quintana, B. koehlerae, and B. henselae seroreactivity was 67.4, 77.0, and 80.7%, respectively. Substantial to almost perfect serological agreement was found between the three Bartonella species. Colony cats were more likely to be Bartonella spp.-seroreactive than owned cats. Moreover, cats aged ≤ 2 years were more likely to be Bartonella spp.-seroreactive. Bartonella spp. DNA was detected in the blood of 11.9% (n = 16) of cats. Cats were infected with B. henselae (n = 12), B. clarridgeiae (n = 3), and B. koehlerae (n = 1). Mycoplasma spp. DNA was amplified from 14% (n = 19) of cat blood specimens. Cats were infected with Mycoplasma haemofelis (n = 8), Candidatus M. haemominutum (n = 6), Candidatus Mycoplasma turicensis (n = 4), and Mycoplasma wenyonii (n = 1). Anaplasma, Babesia, Cytauxzoon, Ehrlichia spp., Hepatozoon, and Theileria spp. DNA was not amplified from any blood sample. Of the 16 Bartonella spp.-infected cats based on PCR results, six (37%) were co-infected with Mycoplasma spp.

Conclusions

Bartonella spp. and hemoplasma infections are prevalent in cats from the Barcelona area, whereas infection with Anaplasma spp., Babesia, Cytauxzoon, Ehrlichia spp., Hepatozoon, and Theileria infections were not detected. Co-infection with hemotropic Mycoplasma appears to be common in Bartonella-infected cats. To our knowledge, this study is the first to document M. wenyonii is infection in cats.

Graphical Abstract

Identification of Streptococcus suis in a cat with endomyocarditis

Case summary

A 3-year-old neutered male domestic mediumhair cat was evaluated for a 4-month history of a fever that was responsive to pradofloxacin. A grade III/VI left parasternal systolic heart murmur was noted on examination. Findings on thoracic radiography were consistent with left-sided congestive heart failure and findings on echocardiographic examination suggested endomyocarditis. Aerobic blood cultures yielded growth of a Streptococcus species that was identified as Streptococcus suis using both matrix-associated laser desorption ionization-time of flight mass spectrometry and 16S rRNA gene sequencing. The cat was treated but clinically deteriorated and was euthanized 23 days after diagnosis.

Relevance and novel information

To our knowledge, this is the first report of S suis bacteremia, an emerging pathogen, in association with endomyocarditis in the cat. This case also highlights the role of echocardiography to document progressive hemodynamic changes as a result of valvular erosion in the course of infective endocarditis treatment and the role of blood cultures as a diagnostic tool in cats presenting with fever.

Updates on Laboratory Evaluation of Feline Cardiac Diseases

Laboratory tests can be altered in cardiovascular diseases and the investigation of specific tests or biomarkers may provide additional information about myocardial damage. Traditional laboratory tests, such as cell blood count, serum biochemistry, and coagulation, can be useful in investigating patients, but are not specific. However, markers like Troponin and Natriuretic Peptides may possibly furnish further data on myocardium damage and can be used in both studying and monitoring cats with cardiac disease. Moreover, the evaluation of the thyroid profile is very important as hyperthyroid cats concomitant cardiovascular diseases are very common and they can also be a direct consequence of endocrinopathy. The purpose of this manuscript is to provide the widest possible overview of what is present in the literature about the feline clinical pathology of heart diseases through a rational division of the main alterations of traditional tests and biomarkers.

Infective vegetative endocarditis of the mitral, aortic, and pulmonary valves due to Enterococcus hirae in a cat with a ventricular septal defect

A 2.5-year-old female intact British Shorthair was presented for progressive complaints of abdominal distention, increased respiratory effort, lethargy and hyporexia. Based on the clinical presentation and a loud heart murmur, a cardiac cause was suspected. An echocardiogram was performed and the presumptive diagnosis of infective endocarditis of the aortic, mitral and pulmonic valves was made. Antemortem blood culture and postmortem valve biopsy confirmed bacterial endocarditis with Enterococcus hirae as etiological agent. To the authors' best knowledge, this case report is the first to describe an infective endocarditis with vegetative lesions on three cardiac valves associated with a ventricular septal defect in a cat, and Enterococcus hirae as causative agent for endocarditis in small animals.

Molecular Survey of Bartonella Species in Shelter Cats in Rio De Janeiro: Clinical, Hematological, and Risk Factors

The present study aimed to detect Bartonella DNA in cats belonging to shelters, and to evaluate risk factors, clinical signs, and hematological abnormalities associated with infection. Complete blood counts and screening for the presence of Bartonella DNA were performed on cats' ethylenediamine tetraacetic acid anticoagulant-blood samples. Eighty-three cats (39.9%) were positive for Bartonella species. Bartonella DNA was also detected in fleas and in the blood of cats infested by positive flea. Cats that had not been sterilized, had outdoor access, had histories of fights, and had concurrent flea infestation were more likely to be infected by Bartonella species (P < 0.05). Age and sex were not associated with infection. Fifty-one (38.6%) symptomatic cats were positive to Bartonella species (P > 0.05). Clinical conditions most commonly observed were signs of respiratory abnormality and Sporothrix species coinfection (P > 0.05). Regarding hematological changes, eosinophilia was associated with infection (P < 0.05). A high frequency of Bartonella species infection was found in shelter cats and highlights the importance of adequate flea-control programs to prevent infection in cats and consequently in adopters and other animals.

Bartonella infections in cats and dogs including zoonotic aspects

Bartonellosis is a vector-borne zoonotic disease with worldwide distribution that can infect humans and a large number of mammals including small companion animals (cats and dogs). In recent years, an increasing number of studies from around the world have reported Bartonella infections, although publications have predominantly focused on the North American perspective. Currently, clinico-pathological data from Europe are more limited, suggesting that bartonellosis may be an infrequent or underdiagnosed infectious disease in cats and dogs. Research is needed to confirm or exclude Bartonella infection as a cause of a spectrum of feline and canine diseases. Bartonella spp. can cause acute or chronic infections in cats, dogs and humans. On a comparative medical basis, different clinical manifestations, such as periods of intermittent fever, granulomatous inflammation involving the heart, liver, lymph nodes and other tissues, endocarditis, bacillary angiomatosis, peliosis hepatis, uveitis and vasoproliferative tumors have been reported in cats, dogs and humans. The purpose of this review is to provide an update and European perspective on Bartonella infections in cats and dogs, including clinical, diagnostic, epidemiological, pathological, treatment and zoonotic aspects.

Necrotizing interstitial pneumonia and suppurative myocarditis associated with Bartonella henselae infection in three Florida pumas

Three Florida pumas ( Puma concolor coryi) that had spent time in captivity prior to being released in the wild were found exhibiting respiratory signs and reluctance to move. All 3 pumas died shortly after immobilization, despite supportive veterinary care. Significant autopsy findings included necrotizing interstitial pneumonia, with pulmonary edema and hyaline membranes, and suppurative myocarditis. Organisms morphologically consistent with Bartonella henselae were identified in intravascular histiocytes in the lung of one of the pumas on histopathology and confirmed via transmission electron microscopy. B. henselae was detected in fresh lung tissue and confirmed by PCR and sequence analysis (16S-23S spacer region, pap31, and rpoB genes) from one of the affected pumas. In all affected pumas, B. henselae was detected by PCR in formalin-fixed, paraffin-embedded lung tissue, and positively staining organisms were identified in sections of lung by immunohistochemistry for B. henselae. In situ hybridization detected B. henselae DNA in lung tissue from 2 of 3 affected pumas. Our case series suggests that B. henselae can be associated with a fatal disease syndrome in Florida pumas. The cause of susceptibility to fatal disease associated with B. henselae infection in these pumas remains unknown.

Bartonella spp. as a Possible Cause or Cofactor of Feline Endomyocarditis-Left Ventricular Endocardial Fibrosis Complex

Endomyocarditis is a commonly detected post-mortem finding in domestic cats presenting for sudden onset cardiovascular death, yet the aetiology remains unresolved. Cats are documented reservoir hosts for Bartonella henselae, the infectious cause of cat scratch disease in man. Various Bartonella spp. have been associated with culture-negative endocarditis, myocarditis and sudden death in man and animals. We hypothesized that Bartonella spp. DNA could be amplified more often from the hearts of cats with feline endomyocarditis-left ventricular endocardial fibrosis (FEMC-LVEF) complex compared with cats with hypertrophic cardiomyopathy (HCM) or cats with grossly and microscopically unremarkable hearts (designated non-cardiac disease controls). Formalin-fixed and paraffin wax-embedded, cardiac tissues from 60 domestic and purebred cats aged 3 months to 18 years were examined, and histological features were recorded. Cardiac tissue sections were tested for Bartonella DNA using multiple 16-23S intergenic transcribed spacer region polymerase chain reaction (PCR) primer sets, including two Bartonella genera, a Bartonella koehlerae species-specific and a Bartonella vinsonii subsp. berkhoffii-specific assay, followed by DNA sequence confirmation of the species or genotype. Special precautions were taken to avoid DNA cross-contamination between tissues. Bartonella spp. DNA was amplified by PCR and sequenced from 18 of 36 cats (50%) with FEMC-LVEF and 1/12 (8.3%) cats with HCM. Bartonella spp. DNA was not amplified from any non-cardiac disease control hearts. Based on PCR/DNA sequencing, one Bartonella spp. was amplified from 10 cats, while the remaining eight were coinfected with more than one Bartonella spp. To our knowledge, this study represents the first documentation of B. vinsonii subsp. berkhoffii genotype I infection in cats (n = 11). Fluorescence in-situ hybridization testing facilitated visualization of Bartonella bacteria within the myocardium of four of seven PCR-positive FEMC-LVEF hearts. Collectively, these findings support the hypothesis that Bartonella spp. may play a primary role or act as a cofactor in the pathogenesis of FEMC-LVEF. Studies involving cats from other geographical regions and definitive demonstration of Bartonella spp. within regions of inflammation are needed to confirm an association between Bartonella spp. and FEMC-LVEF induced morbidity and mortality in cats.

Vector-borne diseases in cats in Germany

Vector-borne diseases (VBDs) are caused by a wide range of pathogens, which are transmitted by a variety of vectors, such as ticks and fleas. As a result of climate changes, more vector-borne diseases are becoming endemic in Germany, not only in dogs, but also in cats. For some of the pathogens prevalence data still need to be investigated in Germany. However, natural infections with Bartonella, Anaplasma, haemotropic Mycoplasma and Borrelia species have already been described in German cats. Clinical relevance of these pathogens is not fully understood, and it is still unknown, why most infected cats stay asymptomatic and which predisposing factors contribute to the development of clinical signs in cats. Moreover, there is a risk of zoonotic transmission for some of the pathogens, e.  g., for some Bartonella spp. infections that are associated with cat scratch disease in humans. Due to the increasing number of VBDs in cats in Germany, preventive measures, such as the use of acaricides and insecticides, should be performed on a regular base in order to reduce the risk of these infections.

Molecular detection of Bartonella henselae in 11 Ixodes ricinus ticks extracted from a single cat

BACKGROUND

Bartonella henselae is a highly prevalent, vector-borne pathogen. Transmission to humans and animals by ticks is discussed controversially. Here, we present a case report, where eleven Ixodes ricinus ticks all harbouring B. henselae DNA were removed from one single cat.

RESULTS

The first feeding tick was tested positive for B. henselae DNA. The cat was also found to be seropositive for anti-B. henselae IgG antibodies (titer 1:640). Bartonella henselae was not cultivatable from cat blood. Ten more feeding ticks removed 7 months later contained also B. henselae DNA. Sequence analysis of the 16SrDNA and the 16S-23S internal transcribed spacer (ITS) region revealed 100% sequence homology between all ticks. Bartonella adhesin A (badA) and VirB/VirD4 type IV secretion system (virB) DNA were also detected in all ticks.

CONCLUSIONS

Our results indicate that cats may serve as a reservoir for adult ticks to acquire B. henselae. Whether this observation implies an increased threat for human and animal health needs to be resolved.

Infective endocarditis in 13 cats

INTRODUCTION

To describe the clinical presentation, clinicopathological abnormalities and outcomes of a series of cats diagnosed with infective endocarditis (IE) at two tertiary care referral institutions.

ANIMALS

Thirteen client-owned cats presenting to the cardiology or emergency services of tertiary referral institutions with a diagnosis of endocarditis based on the modified Duke criteria.

MATERIALS AND METHODS

Retrospective case series. Medical records were reviewed to extract relevant data. In addition, cases that had cardiac tissue available were evaluated by polymerase chain reaction for the presence of Bartonella DNA.

RESULTS

Prevalence of feline IE was 0.007%. Cats with endocarditis tended to be older (median age: 9 years, range: 2-12 years) and no sex or breed was overrepresented. Commonly encountered clinical signs included respiratory distress (n = 5) and locomotor abnormalities of varying severity (n = 5). Echocardiographic examination detected valvular lesions consistent with endocarditis on the aortic (n = 8) or mitral (n = 5) valves. Nine cats were diagnosed with congestive heart failure at the time of endocarditis diagnosis. Overall, prognosis was grave with a median survival time of 31 days.

CONCLUSIONS

In contrast to dogs, cats with IE typically present with clinical signs consistent with cardiac decompensation and locomotor abnormalities suggestive of either thromboembolic disease or inflammatory arthritis. Given the advanced state of disease when diagnosis typically occurs, prognosis is grave.

Bartonella spp. - a chance to establish One Health concepts in veterinary and human medicine

Infectious diseases remain a remarkable health threat for humans and animals. In the past, the epidemiology, etiology and pathology of infectious agents affecting humans and animals have mostly been investigated in separate studies. However, it is evident, that combined approaches are needed to understand geographical distribution, transmission and infection biology of “zoonotic agents”. The genus Bartonella represents a congenial example of the synergistic benefits that can arise from such combined approaches: Bartonella spp. infect a broad variety of animals, are linked with a constantly increasing number of human diseases and are transmitted via arthropod vectors. As a result, the genus Bartonella is predestined to play a pivotal role in establishing a One Health concept combining veterinary and human medicine.

The efficacy of a selamectin (Stronghold ®) spot on treatment in the prevention of Bartonella henselae transmission by Ctenocephalides felis in cats, using a new high-challenge model

Bartonella henselae is the causative agent of cat scratch disease in humans, which is recognized as an emerging zoonotic disease. Ctenocephalides felis is the main vector, and transmission of B. henselae infection between cats and humans occurs mainly through infected flea feces. Control of feline infestation with this arthropod vector therefore provides an important strategy for the prevention of infection of both humans and cats. In the present study, a new challenge model is used to evaluate the efficacy of selamectin (Stronghold^® spot on) in the prevention of B. henselae transmission by C. felis. In this new challenge model, domestic cats were infected by direct application of B. henselae-positive fleas. The fleas used for infestation were infected by feeding on blood that contained in vitro-cultured B. henselae. The direct application of the fleas to the animals and the use of different B. henselae strains ensured a high and consistent challenge. Two groups of six cats were randomly allocated on pre-treatment flea counts to either control (untreated cats) or the selamectin-treated group with one pipette per cat according to the label instruction. Stronghold (selamectin 6 % spot on solution) was administered on days 0 and 32. On days 3, 10, 19, 25, and 31, each cat was infested by direct application of 20 fleas that fed on blood inoculated with B. henselae. Polymerase chain reaction (PCR) on pooled fleas confirmed that the fleas were infected. Blood samples were collected from each cat on days −3 (prior to flea infestation and treatment), 9, 17, 24, 30, 37, and 44 and assayed for B. henselae antibodies using an indirect immunofluorescence (IFA), for the presence of bacteria by bacterial culture and for B. henselae DNA presence by PCR. Cats were also assessed on a daily basis for general health. There were no abnormal health observations during the study and none of the animals required concomitant treatment. None of the cats displayed any clinical signs of bartonellosis during the study. In the untreated group, all cats became bacteremic within 17 to 44 days. None of the selamectin-treated cats became positive during the study. It was concluded that Stronghold^® spot on administered to cats was efficacious in the prevention of the transmission of B. henselae by fleas to cats in a high-challenge model.

Bartonella species infection in cats: ABCD guidelines on prevention and management

OVERVIEW

Over 22 Bartonella species have been described in mammals, and Bartonella henselae is most common worldwide. Cats are the main reservoir for this bacterium. B henselae is the causative agent of cat scratch disease in man, a self-limiting regional lymphadenopathy, but also of other potentially fatal disorders in immunocompromised people.

INFECTION

B henselae is naturally transmitted among cats by the flea Ctenocephalides felis felis, or by flea faeces. A cat scratch is the common mode of transmission of the organism to other animals, including humans. Blood transfusion also represents a risk.

DISEASE SIGNS

Most cats naturally infected by B henselae do not show clinical signs but cardiac (endocarditis, myocarditis) or ocular (uveitis) signs may be found in sporadic cases. B vinsonii subspecies berkhoffii infection has reportedly caused lameness in a cat affected by recurrent osteomyelitis and polyarthritis.

DIAGNOSIS

Isolation of the bacterium is the gold standard, but because of the high prevalence of infection in healthy cats in endemic areas, a positive culture (or polymerase chain reaction) is not confirmatory. Other compatible diagnoses must be ruled out and response to therapy gives a definitive diagnosis. Serology (IFAT or ELISA) is more useful for exclusion of the infection because of the low positive predictive value (39-46%) compared with the good negative predictive value (87-97%). Laboratory testing is required for blood donors.

DISEASE MANAGEMENT

Treatment is recommended in the rare cases where Bartonella actually causes disease.

Chronic Bartonellosis in cats: what are the potential implications?

PRACTICAL RELEVANCE

Bartonellae are small, vector-transmitted Gram-negative intracellular bacteria that are well adapted to one or more mammalian reservoir hosts. Cats are the natural reservoir for Bartonella henselae, which is a (re-)emerging bacterial pathogen. It can cause cat scratch disease in humans and, in immunocompromised people, may lead to severe systemic diseases, such as bacillary angiomatosis. Cats bacteraemic with B henselae constitute the main reservoir from which humans become infected. Most cats naturally infected with B henselae show no clinical signs themselves, but other Bartonella species for which cats are accidental hosts appear to have more pathogenicity.

GLOBAL IMPORTANCE

Several studies have reported a prevalence of previous or current Bartonella species infection in cats of up to 36%. B henselae is common in cats worldwide, and bacteraemia can be documented by blood culture in about a quarter of healthy cats. The distribution of B henselae to various parts of the world has largely occurred through humans migrating with their pet cats. The pathogen is mainly transmitted from cat to cat by fleas, and the majority of infected cats derive from areas with high flea exposure. No significant difference in B henselae prevalence has been determined between male and female cats. In studies on both naturally and experimentally infected cats, chronic bacteraemia has mainly been found in cats under the age of 2 years, while those over 2 years of age are rarely chronically bacteraemic.

EVIDENCE BASE

This article reviews published studies and case reports on bartonellosis to explore the clinical significance of the infection in cats and its impact on humans. The article also discusses possible treatment options for cats and means of minimising the zoonotic potential.

An investigation into the seroprevalence of Toxoplasma gondii, Bartonella spp., feline immunodeficiency virus (FIV), and feline leukaemia virus (FeLV) in cats in Addis Ababa, Ethiopia

Toxoplasma gondii and Bartonella spp. are zoonotic pathogens of cats. Feline immunodeficiency virus (FIV), and feline leukaemia virus (FeLV) are immunosuppressive viruses of cats that can affect T. gondii oocyst shedding. In this study, the prevalence of antibodies to T. gondii, Bartonella spp., FIV, as well as FeLV antigens were determined in sera from feral cats (Felis catus) from Addis Ababa, Ethiopia. Using the modified agglutination test, IgG antibodies to T. gondii were found in 41 (85·4%) of the 48 cats with titres of 1:25 in one, 1:50 in one, 1:200 in six, 1:400 in six, 1:800 in six, 1:1600 in eight, and 1:3200 in 13 cats. Toxoplasma gondii IgM antibodies were found in 11/46 cats tested by ELISA, suggesting recent infection. Antibodies to Bartonella spp. were found in five (11%) of 46 cats tested. Antibodies to FIV or FeLV antigen were not detected in any of the 41 cats tested. The results indicate a high prevalence of T. gondii and a low prevalence of Bartonella spp. infection in cats in Ethiopia.

Detection of Bartonella henselae IgM in serum of experimentally infected and naturally exposed cats

BACKGROUND

Results of Bartonella henselae blood culture, polymerase chain reaction (PCR) assay on blood, or IgG antibody assays do not always correlate with the presence or absence of clinical disease in cats, and B. henselae IgG antibodies in serum do not always correlate with bacteremia. However, little is known concerning Bartonella spp. IgM antibodies in naturally exposed cats.

HYPOTHESIS

Bartonella spp. IgM antibodies in serum are associated with fever, stomatitis, and bacteremia based on PCR assay results in experimentally infected or client-owned cats.

ANIMALS

Stored sera from cats experimentally infected with B. henselae by exposure to Ctenocephalides felis, client-owned cats with and without fever, and client-owned cats with and without stomatitis were studied.

METHODS

A Bartonella spp. IgM ELISA was titrated with samples from experimentally infected cats and then test sera from client-owned cats were assayed. Associations among IgM ELISA results, clinical findings, and bacteremia as defined by Bartonella spp. PCR assay were assessed.

RESULTS

All experimentally infected cats developed Bartonella spp. IgM antibodies. Bartonella spp. IgM antibody assay results were not always in agreement with PCR assay results in client-owned cats (60%). Bartonella spp. DNA in blood, IgM antibodies, and IgG antibodies were not associated with the presence of fever or stomatitis.

CONCLUSIONS AND CLINICAL IMPORTANCE

Because Bartonella spp. IgM antibodies as measured by this assay were not associated with fever or stomatitis and were not always in agreement with PCR assay results, there appears to be little need for assessing individual client-owned cats for this antibody class alone.

Bartonella spp. DNA in cardiac tissues from dogs in Colorado and Wyoming

BACKGROUND

Several Bartonella species (spp.) have been identified in dogs diagnosed with infectious endocarditis (IE) or myocarditis.

OBJECTIVE

To interrogate cardiac tissues of dogs with suspected IE for the presence of Bartonella spp. DNA of dogs in the Rocky Mountain states.

ANIMALS

Nine dogs with a clinical diagnosis of endocarditis from January 1990 to June 2008 were included.

METHODS

In this retrospective study, medical records at the Veterinary Teaching Hospital were searched. Animals were excluded if there was no diagnosis of IE in the original necropsy report. Paraffin embedded tissue blocks and medical records were available from 9 dogs. Total DNA was extracted from the cardiac tissues and assessed for Bartonella spp. DNA by 3 polymerase chain reaction (PCR) methods. For positive samples, the Bartonella spp. were determined by genetic sequencing or fluorogenic real-time PCR.

RESULTS

Bartonella henselae DNA was amplified from the tissues of 7 dogs; Bartonella vinsonii subsp berkhoffii DNA was amplified concurrently from 3 dogs. Six dogs were from Colorado and 1 was from Wyoming. Flea or tick infestations were reported in 2 dogs.

CONCLUSIONS AND CLINICAL IMPORTANCE

Bartonella spp. should be on the differential list for dogs in the Rocky Mountain states. The results emphasize the need for routine use of external parasite control products even in regions perceived to have low risk for flea and tick infestations.

Association between Bartonella species infection and disease in pet cats as determined using serology and culture

This study's objective was to determine whether a relationship exists between infection or seropositivity to Bartonella species and clinical illness in cats. Blood samples were obtained for Bartonella species isolation and immunofluorescent antibody serology from 298 cats presenting to a tertiary referral hospital. Medical records were searched and the history, physical examination findings and the results of diagnostic testing relating to the visit at which Bartonella species testing was performed were recorded. Fifty-two (17%) samples were seropositive for Bartonella henselae, four (1%) for Bartonella clarridgeiae, and 57 (19%) for both organisms. Nineteen (6.4%) samples were culture positive, 17 for B henselae and two for B clarridgeiae. Gingivostomatitis was associated with Bartonella species isolation (P=0.001), but not seropositivity. There was no association with uveitis, neurologic signs, or chronic kidney disease, and a weak association between seropositivity and idiopathic lower urinary tract disease (feline interstitial cystitis) (P=0.05).

Successful treatment of Bartonella henselae endocarditis in a cat

This report describes the clinical presentation, diagnosis and treatment of a cat with vegetative valvular endocarditis temporally associated with natural infection with Bartonella henselae. Lethargy, abnormal gait and weakness were the main clinical signs that resulted in referral for diagnostic evaluation. Using a novel and sensitive culture approach, B henselae was isolated from the blood. Following antibiotic therapy there was total resolution of clinical signs, the heart murmur, the valvular lesion by echocardiography, and no Bartonella species was isolated or amplified from a post-treatment blood culture. In conjunction with previous case reports, infective endocarditis can be associated with natural B henselae infection in cats; however, early diagnosis and treatment may result in a better prognosis than previously reported.

Emergent opportunities in humans: playful kittens, an arthropod vector, and a zoonotic agent

Bartonella henselae is implicated as the main etiologic agent of Cat scratch disease (CSD, Cat-scratch fever). A majority of domestic cats may harbor the intra-erythrocytic agent for extended periods without apparent disease. In humans, B. henselae most commonly results in a subacute, bacterial infection that presents with one or more reddish papules which may progress to pustules and regional lymph node enlargement. Usual features include fever, malaise, and a granulomatous lymphadenitis on biopsy. However, atypical clinical presentations occur, albeit with infrequence, and may result in a difficult and protracted diagnostic process. The infection in susceptible hosts such as immunocompromised or elderly patients may result in endocarditis, encephalitis, fever of unknown origin, and general malaise. It is not transmitted from person to person and quarantine is not necessary. The arthropod vector, Ctenocephalides felis, or the cat flea, plays a major role in transmission among cats and to humans. The transmission risk to humans can be substantially reduced through elimination of flea infestations in companion animals. There are numerous recent reviews and case reports in the veterinary and medical literature reflecting increased recognition of this zoonotic agent. All this notwithstanding, many physicians and other providers may not be familiar with this agent and the potential spectrum of human disease; this may lead to delays in diagnosis and unnecessary diagnostic procedures. This article emphasizes the aspects of B. henselae infection, including a typical case report and a table with selected human case reports of unusual clinical manifestations from the published literature.

Association of Bartonella species, feline calicivirus, and feline herpesvirus 1 infection with gingivostomatitis in cats

Feline gingivostomatitis (FGS) is a common syndrome in cats; feline calicivirus (FCV), feline herpesvirus 1 (FHV-1), and Bartonella species are common differential diagnoses. In this study, blood from 70 cats with FGS and 61 healthy control cats was tested for Bartonella species antibodies in serum by enzyme-linked immunosorbent assay and Western blot immunoassay and DNA in blood using a conventional polymerase chain reaction assay. Additionally, fresh oral biopsies from cats with FGS (n=42) and 19 healthy controls were tested for FCV RNA, FHV-1 DNA and Bartonella species DNA. The prevalence rates for Bartonella species antibodies and DNA in the blood and the tissues did not differ between the two groups. FHV-1 DNA was also not significantly different between groups. Only FCV RNA was present in significantly more cats with FGS (40.5%) than control cats (0%). The results suggest that FCV was associated with FGS in some of the cats.

Molecular detection of Bartonella henselae and Bartonella clarridgeiae in clinical samples of pet cats from Southern Italy

Bartonella henselae is considered an emerging pathogen of veterinary and medical interest that can be occasionally transmitted to humans. Cats are considered to be the only reservoir host for B. henselae. In this study, we used a nested-PCR assay to investigate the prevalence of B.henselae and Bartonella clarridgeiae DNA in peripheral blood samples, fine needle lymph node aspirate specimens and oral swabs from 85 cats in order to develop an easy diagnostic strategy for the selection of infection-free cats that are being considered as pets, especially for immunocompromised patients. Overall, molecular analysis showed that 71 cats (83.5%) tested PCR positive for the presence of B. henselae DNA. PCR amplification of DNA B. henselae produced positive products from lymph node aspirate specimens (62/85; 72.9%) similar to those obtained from blood samples (60/85; 70.6%) and higher than those from oral swabs (51/85; 60%) of cats. No PCR product was obtained for B. clarridgeiae. The simultaneous analysis of three different clinical samples in our study increased the diagnostic possibilities for B. henselae infection in the examined cats from 60-72.9% to 83.5%. Lymph node aspirates were found to be the most effective clinical samples for the detection of B. henselae and blood samples were the next best. Oral swab samples were used in this study with good results when considered in combination with blood and/or lymph node aspiration. The use of nested-PCR assay on these three clinical samples may enhance the diagnostic sensitivity for bartonellosis in cats irrespective of the clinical status of animals.

Microbial culture of blood samples and serologic testing for bartonellosis in cats with chronic rhinosinusitis

OBJECTIVE

To assess the role of Bartonella spp in chronic rhinosinusitis (CRS) by determining detection rates for the organism by serologic testing and microbial culture of blood samples for Bartonella spp in cats with CRS and control cats (cats with other nasal diseases, cats with systemic illnesses, and healthy cats).

DESIGN

Prospective case-control study.

ANIMALS

19 cats with CRS, 10 cats with other nasal diseases, 15 cats with systemic illness, and 15 healthy cats. Procedures-Serologic testing for Bartonella clarridgeiae and Bartonella henselae and microbial culture of blood samples were conducted in all cats. In cats with CRS and cats with other nasal diseases, a nasal biopsy specimen was submitted, when available, for tissue PCR assay to detect Bartonella spp.

RESULTS

9 of 19 cats with CRS had positive results for serologic testing for 1 or both Bartonella spp; whereas, 4 of 10 cats with other nasal diseases, 2 of 15 cats with systemic diseases, and 4 of 15 healthy cats had positive results for serologic testing to detect Bartonella spp. These values did not differ significantly among groups. Microbial culture of blood samples yielded B henselae in 1 cat with a nasopharyngeal abscess. The PCR assay for Bartonella spp in nasal tissues yielded negative results for 9 of 9 cats with CRS and 5 of 5 cats with other nasal diseases.

CONCLUSIONS AND CLINICAL RELEVANCE

A role for Bartonella spp in the pathogenesis of CRS in cats was not supported by results of this study.

PCR detection of Bartonella bovis and Bartonella henselae in the blood of beef cattle

Although an organism primarily associated with non-clinical bacteremia in domestic cattle and wild ruminants, Bartonella bovis was recently defined as a cause of bovine endocarditis. The purpose of this study was to develop a B. bovis species-specific PCR assay that could be used to confirm the molecular prevalence of Bartonella spp. infection. Blood samples from 142 cattle were tested by conventional PCR targeting the Bartonella 16S-23S intergenic spacer (ITS) region. Overall, Bartonella DNA was detected in 82.4% (117/142) of the cattle using either Bartonella genus primers or B. bovis species-specific primers. Based upon size, 115 of the 117 Bartonella genus ITS PCR amplicons were consistent with B. bovis infection, which was confirmed by PCR using B. bovis species-specific primers and by sequencing three randomly selected, appropriately sized Bartonella genus PCR amplicons. By DNA sequencing, Bartonella henselae was confirmed as the two remaining amplicons, showing sequence similarity to B. henselae URBHLIE 9 (AF312496) and B. henselae Houston 1 (NC_005956), respectively. Following pre-enrichment blood culture of 12 samples in Bartonella alpha Proteobacteria growth medium (BAPGM) B. henselae infection was found in another three cows. Four of the five cows infected with B. henselae were co-infected with B. bovis. To our knowledge this study describes the first detection of B. henselae in any large ruminant species in the world and supports the need for further investigation of prevalence and pathogenic potential of B. henselae and B. bovis in cattle.

P26-based serodiagnosis for Bartonella spp. infection in cats

Bartonella henselae P26 has been identified as an immunodominant antigen expressed during feline infection. We used antisera from cats experimentally infected with B. henselae (n = 6), B. clarridgeiae (n = 4), or B. koehlerae (n = 2) and from a sample of naturally infected cats (B. henselae, n = 34; B. clarridgeiae, n = 1) to evaluate recombinant P26 (rP26) as a serodiagnostic antigen. Immunoblots using antisera from cats infected with B. henselae and B. clarridgeiae reacted strongly with rP26, whereas B. koehlerae antisera did not. A capture ELISA was designed to evaluate the kinetics of rP26 IgG in sera from experimentally infected cats. For B. henselae and B. clarridgeiae antisera, the kinetic profiles of reactivity were similar for rP26 capture ELISA and Bartonella spp. indirect fluorescence assay. However, for B. koehlerae antisera, reactivity in rP26 capture ELISA was consistently low. The serodiagnostic potential of rP26 capture ELISA was evaluated using sera from cats with known Bartonella sp. exposure histories. All 24 (100%) uninfected cats were seronegative, and 33 of 35 (94.3%) cats bacteremic for Bartonella spp. were seropositive. We propose that rP26-based serology can serve as a useful adjunct tool for the diagnosis of feline infection with B. henselae and B. clarridgeiae, but it may not be useful for feline infection with B. koehlerae.

Endocarditis in cattle caused by Bartonella bovis

This study aimed to determine the role of Bartonella as an endocarditis agent in cattle. Bartonella bovis was identified by PCR, gene sequences analysis, and specific internal transcribed spacer amplicon product size in 2 bovine endocarditis cases with high antibody titers, which demonstrates that B. bovis is a pathogen for cattle.

Evaluation of the association of Bartonella species, feline herpesvirus 1, feline calicivirus, feline leukemia virus and feline immunodeficiency virus with chronic feline gingivostomatitis

Gingivostomatitis (GS) is a significant condition in cats because of oral discomfort and associated periodontal disease. Several infectious agents have been associated with the presence of GS, but a causal relationship is unclear. The cats in this study were housed together, had a history of flea exposure, and were vaccinated with a modified live FVRCP product. There were nine cats with active GS and 36 unaffected cats at the time of sample collection. Serum was tested for feline leukemia virus (FeLV) antigen and antibodies against feline immunodeficiency virus, feline calicivirus (FCV), feline herpesvirus 1 (FHV-1), and Bartonella species (enzyme-linked immunosorbent assay and Western blot immunoassay). PCR assays for Bartonella species and FHV-1 and a reverse transcriptase PCR assay for FCV were performed on blood and throat swabs. All cats were negative for FeLV. Assay results failed to correlate to the presence of GS in the group of cats studied.

Development of discriminatory multiple-locus variable number tandem repeat analysis for Bartonella henselae

Bartonella henselae is a zoonotic bacterium that infects cats and humans. Several attempts have been made to develop typing techniques for epidemiological purposes; however, most of the techniques developed do not appear to be sufficiently discriminatory or easy to use. In order to develop multilocus variable number tandem repeat (VNTR) analysis (MLVA) for B. henselae, 30 VNTR candidates were selected from the genome sequence of the reference strain Houston 1 (H1). The VNTR candidates were initially tested by PCR on six B. henselae isolates from different geographical areas. Five VNTRs were selected from those that showed two or more alleles. These five B. henselae VNTRs (BHVs) were tested on 42 feline B. henselae isolates and strains from France (23 isolates), Denmark (17 isolates), the Philippines (one isolate) and the USA (F1 strain), on one human isolate from Germany, and on the H1 reference strain. These BHVs were sufficiently discriminatory to obtain 31 different profiles (corresponding to two different groups) among the 44 isolates and strains of B. henselae tested. Thirty-five profiles were obtained using these BHVs and two variant alleles. The combination of the five markers led to a diversity index of 0.98. The stability of the five BHVs was demonstrated on the feline F1 strain, with no change in stability observed after 2, 21 and 41 passages. This is believed to be the first study conducted on B. henselae typing using MLVA, and it demonstrates the high quality of this technique for discriminating between B. henselae isolates.

Bartonella henselae Pap31, an extracellular matrix adhesin, binds the fibronectin repeat III13 module

Bartonella henselae wound-associated infections suggest involvement of extracellular matrix molecules in adhesion and invasion. Pap31 was previously identified as a hemin-binding protein. Our recent studies suggest the protein is an adhesin that is recognized by the host's immune systems. In this study we examined the interactions of B. henselae Pap31 with fibronectin (Fn), heparin (Hep), and human umbilical vein endothelial cells (HUVECs). The cloned gene was expressed in Escherichia coli, and the purified Pap31 protein elicited strong antibody responses in mice and was reactive with rabbit anti-live B. henselae and mouse anti-Pap31 antibodies by Western blotting. Pap31 bound to immobilized Fn and to HUVECs in a dose-dependent manner and to Hep. Fn fragment-binding assays identified the Hep-1 and Hep-2 binding domains of human Fn and in particular the (12-13)FnIII repeat module as primary binding sites for this adhesin. Furthermore, Pap31 binding to the above Fn fragments could be inhibited by Hep, suggesting a common binding site involving the 13FnIII repeat module on the Hep-2 domain of Fn. Adherence of intact B. henselae to HUVECs was inhibited by increasing concentrations of anti-Pap31 antibodies. In addition, purified Pap31 coprecipitated effectively with Fn and anti-Fn antibodies. Taken together, these data suggest that Pap31 is an Fn-binding protein mediating the B. henselae-host interaction(s), and they implicate the 13FnIII repeat module as an important binding site for this adhesin on the Fn molecule. These interactions may be important initial steps leading to bacterial attachment and colonization that promote the establishment of B. henselae infections in vivo.

Effects of cow age and pregnancy on Bartonella infection in a herd of dairy cattle

Bartonella spp. are small hemotropic bacteria infecting mammals. Four Bartonella species have been recently described in cattle and wild ruminants. To date, the biology and possible pathogenic role of Bartonella species isolated from ruminants are poorly understood. Therefore, a dairy herd of 448 cows and heifers was surveyed in order to establish the prevalence of Bartonella bovis and B. chomelii infections, the level of bacteremia, and the relationship between bacteremia and age or pregnancy status. The putative impact of Bartonella infection on production performance (individual milk cell count, milk yield) and reproductive status (success of artificial insemination [AI], placental retention, embryonic death, and abortion) was also assessed. The overall mean prevalence of B. bovis bacteremia was 59%, with the highest prevalence in heifers (92.5%). No B. chomelii was isolated, and 95% (114/120) of the B. bovis strains isolated and tested by PCR-restriction fragment length polymorphism belonged to type I. The level of bacteremia was higher in pregnant cows than in nonpregnant cows (P = 0.05), and the level of bacteremia rose during the last two-thirds of gestation (P < 0.001). There was no correlation between bacteremia and milk yield, individual milk cell count, success of first AI, interval between two calvings, or incidence of abortion and embryonic death. The interval from calving to first AI was shorter and the incidence of placental retention was lower in bacteremic animals than in nonbacteremic ones (P = 0.03 and P = 0.01, respectively).

Suspected toxoplasma-associated myocarditis in a cat

Clinical toxoplasmosis is commonly reported in the cat, with the most consistent findings being ocular, pulmonic, hepatic, neurological, gastrointestinal and muscular abnormalities. Myocarditis, whilst frequently identified at post-mortem examination, has not been identified ante-mortem. In immunocompromised humans, myocarditis associated with toxoplasmosis is not an uncommon complication. In such cases, lymphocytic myocardial infiltration can lead to depressed myocardial function, which can be associated with congestive heart failure, rhythm disturbances and pericardial effusions. In addition, myocardial failure has been reported in immunocompetent humans associated with active toxoplasmosis [Chandenier J, Jarry G, Nassif D, Douadi Y, Paris L, Thulliez P, Bourges-Petit E, Raccurt C (2000) Congestive heart failure and myocarditis after seroconversion for toxoplasmosis in two immunocompetent patients. European Journal of Clinical Microbiological Infectious Disease 19, 375-379]. Here we describe a cat with echocardiographic changes consistent with infiltrative or inflammatory disease, and elevated IgG and IgM titres to Toxoplasma gondii. There was resolution of these myocardial changes once the toxoplasmosis was treated.

Canine and feline blood donor screening for infectious disease

Consensus Statements of the American College of Veterinary Internal Medicine (ACVIM) provide veterinarians with guidelines regarding the pathophysiology, diagnosis, or treatment of animal diseases. The foundation of the Consensus Statement is evidence‐based medicine, but if such evidence is conflicting or lacking, the panel provides interpretive recommendations on the basis of their collective expertise. The Consensus Statement is intended to be a guide for veterinarians, but it is not a statement of standard of care or a substitute for clinical judgment. Topics of statements and panel members to draft the statements are selected by the Board of Regents with input from the general membership. A draft prepared and input from Diplomates is solicited at the Forum and via the ACVIM Web site and incorporated in a final version. This Consensus Statement was approved by the Board of Regents of the ACVIM before publication.

Canine and feline blood donor screening for infectious disease

Thousands of blood transfusions are performed each year on dogs and cats, and the demand for blood products continues to grow. Risks associated with transfusions include the risk of disease transmission. Appropriate screening of blood donors for bloodborne infectious disease agents should be performed to lessen this risk. Geographic restrictions of disease, breed predilection, and documentation of actual disease transmission by transfusion all are factors that might need to be considered when making a decision on what screening program to use. In addition, factors involving general health care and management of blood donors should be employed to further ensure blood safety.

A review of bacterial pathogens inCtenocephalides felisin New Zealand

The cat flea, Ctenocephalides felis, is the recognised vector of Bartonella henselae, B. clarridgeiae and Rickettsia felis. Although these Gram-negative bacteria were only described in the last decade, they are already known to cause a variety of diseases in people, particularly children and the immunosuppressed. Such diseases include cat-scratch disease, bacillary angiomatosis, endocarditis, bacteraemia, encephalopathy, neuroretinitis, osteomyelitis and peliosis hepatis. Although most infections in cats and dogs appear to be subclinical, recent studies have provided growing evidence that the bartonellas can also cause serious problems in pets, including hepatitis, endocarditis, central nervous system (CNS) signs, lymphadenopathy, uveitis, cataracts and reproductive failure. In 2004, DNA of B. henselae, B. clarridgeiae and R. felis was demonstrated in cat fleas from New Zealand and pets and their owners in the country are thus at risk of infection. While flea control programmes have traditionally been advocated by veterinarians to prevent pruritus and tapeworms in pets, they should now also be recommended to prevent infections with the new flea-borne bacterial pathogens. To raise awareness of the organisms amongst veterinarians and animal health workers, this review describes: the biology of the organisms; clinical and laboratory features of infections in cats, dogs and people; diagnosis; and possible treatments and control of infections with these organisms.

Molecular Detection of Bartonella henselae DNA in the Dental Pulp of 800-Year-Old French Cats

Bartonella species are responsible for chronic bacteremia in domestic cats, which raises a question about the antiquity of the relationship between Bartonella species and cats that act as reservoirs for the organism. The sequencing of Bartonella pap31 and groEL genes from the dental pulp of cats dating from the 13th to 16th centuries identified the presence of B. henselae genotype Houston; the observation of a unique mutation in the results of PCR assays for Bartonella species ruled out modern DNA contamination of the dental pulp samples. We conclude that cats had bacteremia due to B. henselae 800 years ago.