Review and statistical analysis of clinical management of feline leishmaniosis caused by Leishmania infantum

Background

There is limited information about feline leishmaniosis (FeL) management in clinical practice. Leishmania infantum is the species of Leishmania most frequently reported in both dogs and cats in countries of the Mediterranean region (henceforth ‘Mediterranean countries’), Central and South America, and Iran. This study was conducted to provide veterinary clinicians with an updated overview of evidence-based information on leishmaniosis in cats.

Methods

A review was performed using PubMed, Science Direct, Google Scholar and Web of Science. Case reports of FeL caused by L. infantum were sought for the period 1912 to 1 June 2021.

Results

Sixty-three case reports are included in this review. Fifty-nine out of the 63 cats were from Europe, mostly from Mediterranean countries (88.9%). Most of them were domestic short-haired cats (90%) with a mean age of 7.9 years, and had access to the outdoors (77.3%). Sixty-six percent of the cats had comorbidities, of which feline immunodeficiency virus infection was the most frequent (37.7%). Dermatological lesions (69.8%) was the most frequent clinical sign, and hyperproteinemia (46.3%) the most frequent clinicopathological abnormality. Serology was the most performed diagnostic method (76.2%) and was positive for 93.7% of cats. Medical treatment was applied in 71.4% of cats, and allopurinol was the most used drug (74.4%). Survival time was greater for treated cats (520 days; 71.4% of cats) than non-treated cats (210 days; 25.4%).

Conclusions

The majority of the cats had comorbidities, of which feline immunodeficiency virus was the most frequent. Dermatological lesions were frequently reported, and systemic clinical signs and clinicopathological abnormalities were also common. Serology may be useful for the diagnosis of FeL in clinical practice, and a positive titer of ≥ 1/40 may be a useful cut-off for sick cats. The reported treatments and dosages varied, but there was a good clinical response and longer survival in most of the cats treated with allopurinol monotherapy.

Graphical abstract

Effect of a Pheromone on Stress-Associated Reactivation of Feline Herpesvirus-1 in Experimentally Inoculated Kittens

Background

Stress contributes to reactivation of feline herpesvirus‐1 (FHV‐1). The usage of pheromones to decrease stress in FHV‐1 experimentally inoculated kittens has not previously been investigated.

Hypothesis/Objectives

To determine whether a feline pheromone would lessen stress, resulting in decreased recurrence of FHV‐1‐associated illness in kittens.

Animals

Twelve 5‐month‐old, purpose‐bred kittens.

Methods

Randomized, double‐blind, placebo‐controlled clinical trial. Kittens previously infected with the same dose of FHV‐1 were randomized into 2 separate but identical group rooms. After a 2‐week equilibration period, a diffuser containing either the pheromone or placebo was placed in each of the rooms, and the kittens acclimated for an additional 2 weeks. Every 2 weeks thereafter, for the 8‐week study period, housing was alternated between kennel‐ and group housing. Blinded observers applied a standardized clinical and behavioral scoring rubric daily. After each 2‐week period, serum cortisol concentrations and quantitative PCR for FHV‐1 and glyceraldehyde 3‐phosphate dehydrogenase (GAPDH) ratios were evaluated. Clinical, behavioral, and laboratory test results were compared between groups within individual and combined study periods.

Results

Sneezing occurred more frequently in the placebo group during individual (P = 0.006) and combined study periods (P = 0.001). Sleep at the end of observation periods occurred more frequently in the pheromone group during individual (P = 0.006) and combined study periods (P < 0.001).

Conclusions and Clinical Importance

The findings suggest that the pheromone decreased stress, and the decrease in stress response may have resulted in decreased sneezing associated with FHV‐1.

Effect of Enterococcus Faecium Strain SF68 on Gastrointestinal Signs and Fecal Microbiome in Cats Administered Amoxicillin-Clavulanate

Some cats develop vomiting or diarrhea during administration of some antibiotics such as amoxicillin-clavulanate but how often this occurs and the severity of disease is generally unknown. In people, one of the accepted indications for the use of probiotics is to attempt and lessen antibiotic-associated diarrhea. Enterococcus faecium strain SF68 (SF68; Purina^® ProPlan^® Veterinary Diets; FortiFlora™ Probiotic Supplement) is a commercially available probiotic available in many countries that has been shown to lessen diarrhea rates in cats housed in animal shelters. The objectives of this study were to describe the gastrointestinal abnormalities (clinical and microbiome) associated with the administration of amoxicillin-clavulanate to cats and to determine whether feeding SF68 could ameliorate those abnormalities. Laboratory reared domestic cats were administered amoxicillin-clavulanate for 7 days with or without SF68 for 14 days and monitored for vomiting and diarrhea and for changes in the gastrointestinal microbiome before and after antibiotic administration. Fecal scores > 5 on a 7-point scale were detected in 9 of 13 cats (69.2%) fed SF68 compared to 12 of 14 cats fed the placebo (85.7%). Fecal scores of 7 were only detected in the placebo group and when total diarrhea scores were compared between groups for days 1-11, the cats fed SF68 were statistically lower (P = 0.0058). Administration of amoxicillin-clavulanate led to decreased microbiome diversity, but differences between cats fed SF68 or the placebo were not detected. The results show administering amoxicillin-clavulanate orally to cats commonly induces diarrhea and alters the gastrointestinal microbiome, and that feeding the probiotic SF68 can lessen some associated clinical abnormalities.

A Retrospective Study on the Safety and Efficacy of Leflunomide in Dogs

Background

Little clinical information is available concerning the use of leflunomide in dogs with immune‐mediated diseases.

Objectives

To report the safety and efficacy of leflunomide for the treatment of naturally occurring immune‐mediated diseases in dogs.

Animals

Ninety‐two dogs treated with leflunomide for management of suspected immune‐mediated diseases.

Methods

Retrospective medical record review from Jan 1995 to Dec 2014. Data that were extracted from the medical records included signalment, body weight, underlying indication for leflunomide, dosage of leflunomide, treatment duration, concurrent medications, treatment response, and adverse events.

Results

Adverse events that could be related to leflunomide administration included diarrhea (3 of 92, 3.3%), lethargy (2 of 92, 2.2%), unexplained hemorrhage (3 of 92, 3.3%), thrombocytopenia (2 of 31, 6.5%), and increased liver enzyme activities (1 of 16, 6.3%). Significant dose differences between dogs with adverse events (n = 11; median, 2.9 mg/kg/d; range, 1.8–3.6 mg/kg/d) and dogs without adverse events (n = 81; median, 1.6 mg/kg/d; range, 0.8–4.3 mg/kg/d) were found (P < 0.001). Treatment response could be evaluated in 17 dogs. Of these 17 dogs, 12 dogs (70.5%) had an apparent positive response to the use of leflunomide. There was no significant difference (P = 0.22) in dosages between dogs that responded to leflunomide (n = 12; median, 1.9 mg/kg/d; range, 1.0–3.5 mg/kg/d) and those that did not respond (n = 5; median, 1.7 mg/kg/d; range, 1.0–2.0 mg/kg/d).

Conclusions and Clinical Importance

Results suggest that the starting dosage of leflunomide should be 2 mg/kg/d rather than the currently suggested dosage of 3–4 mg/kg/d.

Serologic responses to peptides of Anaplasma phagocytophilum and Borrelia burgdorferi in dogs infested with wild-caught Ixodes scapularis

Anaplasma phagocytophilum and Borrelia burgdorferi are both transmitted by Ixodes spp. and are associated with clinical illness in some infected dogs. This study evaluated canine antibody responses to the A. phagocytophilum p44 peptides APH-1 and APH-4 as well as the B. burgdorferi C6 peptide before and after doxycycline treatment. A total of eight dogs were infested with wild-caught I. scapularis for 1 week. Blood was collected prior to tick attachment and from Days 3-77 to 218-302 with doxycycline treatment beginning on Day 218. Blood was assayed for A. phagocytophilum DNA by PCR assay. Sera was assessed for antibodies by immunofluorescent antibody (IFA) test and ELISA. Anaplasma phagocytophilum DNA was amplified from blood of all dogs by Day 7. Antibodies to APH-4 were detected in serum as early as 14days after tick exposure and six dogs had APH-4 antibodies detected 3-7 days before antibodies against APH-1. All dogs were seropositive for A. phagocytophilum from Days 218 to 302. Antibodies to B. burgdorferi were detected in 6/8 dogs beginning 21days after I. scapularis infestation. Among the five dogs that remained seropositive at Day 218, C6 antibody levels declined on average 81% within 84days of initiating treatment. The results suggest that the APH-4 peptide may be more useful than APH-1 for detecting antibodies earlier in the course of an A. phagocytophilum infection. After doxycycline administration, C6 antibody levels but not APH-1 or APH-4 antibody levels decreased, suggesting a treatment effect on C6 antibody production.

Prevalence of Enteropathogens in Dogs Attending 3 Regional Dog Parks in Northern California

Background

The prevalence and risk factors for infection with enteropathogens in dogs frequenting dog parks have been poorly documented, and infected dogs can pose a potential zoonotic risk for owners.

Hypothesis/Objectives

To determine the prevalence and risk factors of infection with enteropathogens and zoonotic Giardia strains in dogs attending dog parks in Northern California and to compare results of fecal flotation procedures performed at a commercial and university parasitology laboratory.

Animals

Three‐hundred dogs attending 3 regional dog parks in Northern California.

Methods

Prospective study. Fresh fecal specimens were collected from all dogs, scored for consistency, and owners completed a questionnaire. Specimens were analyzed by fecal centrifugation flotation, DFA, and PCR for detection of 11 enteropathogens. Giardia genotyping was performed for assemblage determination.

Results

Enteropathogens were detected in 114/300 dogs (38%), of which 62 (54%) did not have diarrhea. Frequency of dog park attendance correlated significantly with fecal consistency (P = .0039), but did not correlate with enteropathogen detection. Twenty‐seven dogs (9%) were infected with Giardia, and genotyping revealed nonzoonotic assemblages C and D. The frequency of Giardia detection on fecal flotation was significantly lower at the commercial laboratory versus the university laboratory (P = .013), and PCR for Giardia was negative in 11/27 dogs (41%) that were positive on fecal flotation or DFA.

Conclusions and Clinical Importance

Enteropathogens were commonly detected in dogs frequenting dog parks, and infection with Giardia correlated with fecal consistency. PCR detection of Giardia had limited diagnostic utility, and detection of Giardia cysts by microscopic technique can vary among laboratories.

Update on Canine and Feline Blood Donor Screening for Blood-Borne Pathogens

An update on the 2005 American College of Veterinary Internal Medicine (ACVIM) Consensus Statement on blood donor infectious disease screening was presented at the 2015 ACVIM Forum in Indianapolis, Indiana, followed by panel and audience discussion. The updated consensus statement is presented below. The consensus statement aims to provide guidance on appropriate blood‐borne pathogen testing for canine and feline blood donors in North America.

An Immunohistochemical and Polymerase Chain Reaction Evaluation of Feline Plasmacytic Pododermatitis

Sections of 14 skin biopsies of cats with plasmacytic pododermatitis and a clinical follow-up of 12–36 months were stained with a polyclonal anti- Mycobacterium bovis (Bacille Calmette-Guerin = BCG) antibody cross-reactive to a broad spectrum of fungi and bacteria. All sections were negative for organisms within the actual footpad tissue with the anti-BCG antibody stains. Polymerase chain reaction (PCR) assays that amplify the DNA of Bartonella spp., Ehrlichia spp., Anaplasma phagocytophilum, Chlamydophila felis, Mycoplasma spp., Toxoplasma gondii, and feline herpesvirus 1 (FHV-1) were applied to tissue digests. DNA of those pathogens assessed was not amplified from tissue.

Adenovirus 2, Bordetella bronchiseptica, and Parainfluenza Molecular Diagnostic Assay Results in Puppies After vaccination with Modified Live Vaccines

Background

Canine adenovirus 2, parainfluenza, and Bordetella bronchiseptica cause respiratory disease in dogs, and each has a modified live intranasal vaccine available. Molecular diagnostic assays to amplify specific nucleic acids are available for each of these agents. If positive molecular diagnostic assay results are common after vaccination, the positive predictive value of the diagnostic assays for disease would be decreased.

Objective

To determine the impact of administration of commercially available modified live topical adenovirus 2, B. bronchiseptica, and parainfluenza vaccine has on the results of a commercially available PCR panel.

Animals

Eight puppies from a research breeding facility negative for these pathogens.

Methods

Blinded prospective pilot study. Puppies were vaccinated with a single dose of modified live topical adenovirus 2, B. bronchiseptica, and parainfluenza and parenteral dose of adenovirus 2, canine distemper virus, and parvovirus. Nasal and pharyngeal swabs were collected on multiple days and submitted for PCR assay.

Results

Nucleic acids of all 3 organisms contained in the topical vaccine were detected from both samples multiple times through 28 days after vaccination with higher numbers of positive samples detected between days 3 and 10 after vaccination.

Conclusions and Clinical Importance

Vaccine status should be considered when interpreting respiratory agent PCR results if modified live vaccines have been used. Development of quantitative PCR and wild‐type sequencing are necessary to improve positive predictive value of these assays by distinguishing vaccinate from natural infection.

Concurrent administration of an intranasal vaccine containing feline herpesvirus-1 (FHV-1) with a parenteral vaccine containing FHV-1 is superior to parenteral vaccination alone in an acute FHV-1 challenge model

The administration of intranasal (IN) or subcutaneous (SC) vaccines containing modified live feline herpesvirus 1 (FHV-1) offers some level of protection against FHV-1 challenge, but relative efficacy is <100%. In this study, clinical signs and viral shedding in kittens were compared among three groups: (1) kittens vaccinated concurrently with IN and SC vaccines containing FHV-1 (Group 1, n = 8); (2) kittens vaccinated with a SC FHV-1 vaccine alone (Group 2, n = 8), and (3) unvaccinated control kittens (Group 3, n = 8). All kittens were FHV-1 naïve at enrolment, and challenge with a virulent strain of FHV-1 was performed 1 week after vaccination. Daily clinical signs and pharyngeal FHV-1 shedding were recorded over a 21-day infection period. Overall, kittens in Group 1 had significantly less severe clinical illness than those in Group 2 (P < 0.05). Additionally, significantly less FHV-1 DNA was detected on pharyngeal swabs from kittens in Group 1 compared to those in Group 2 (P < 0.001). Concomitant administration of IN and SC FHV-1 vaccines was superior to administration of the SC FHV-1 vaccine alone in this challenge model of FHV-1 naïve kittens.

Vaccine-associated Leptospira antibodies in client-owned dogs

Background

Long‐term microscopic agglutination test (MAT) results after vaccination with 4‐serovar Leptospira vaccines are not available for all vaccines used in client‐owned dogs.

Hypothesis/Objectives

To determine antibody responses of client‐owned dogs given 1 of 4 commercially available Leptospira vaccines.

Animals

Healthy client‐owned dogs (n = 32) with no history of Leptospira vaccination for at least the previous year.

Methods

Dogs were given 1 of 4 Leptospira vaccines on week 0 and then approximately on week 3 and week 52. Sera were collected before vaccine administration on week 0 and then within 3 days of week 3, within 2 days of week 4, and approximately on weeks 7, 15, 29, 52, and 56. Antibody titers against Leptospira serovars bratislava, canicola, grippotyphosa, hardjo, icterohemorrhagiae, and pomona and were determined by MAT.

Results

When compared among vaccines, MAT results varied in maximal titers, the serovars inducing maximal titers, and the time required to reach maximal titers. Each vaccine induced at least some MAT titers ≥1 : 800. Most dogs were negative for antibodies against all serovars 1 year after vaccination, and anamnestic responses were variable.

Conclusions and Clinical Importance

Dogs vaccinated with Leptospira vaccines have variable MAT titers over time, and antibodies should not be used to predict resistance to Leptospira infection. MAT titers ≥1 : 800 can develop after Leptospira spp. vaccination, which can complicate the clinical diagnosis of leptospirosis.

2013 AAFP Feline Vaccination Advisory Panel Report

Regrettably, two errors appeared in the 2013 AAFP Feline Vaccination Advisory Panel Report. Firstly, in the ‘Injectable vaccine administration’ box, on page 798, the pictures in Figures 8 and 9 were swapped with each other. The amended box is reproduced here. Secondly, the penultimate sentence in the second ‘Trap–Neuter–Return’ FAQ on page 804 should have read: ‘In contrast, only inactivated vaccines resulted in a high rate of protective antibodies against FHV-1,’ and not ‘In contrast, only modified-live vaccines …’. The errors appear in the printed copies of the journal, and in online versions downloaded before November 2013.

DOI of original article: 10.1177/1098612X13500429

DOI: 10.1177/1098612X13511888

Analysis of seroreactivity against cell culture-derived Bartonella spp. antigens in dogs

BACKGROUND

Little is known about the specificity of Bartonella spp. immunofluorescent antibody (IFA) assays in dogs. Bacteremia in sick dogs most often has been associated with Bartonella henselae (Bh), Bartonella vinsonii subspecies berkhoffii (Bvb), and Bartonella koehlerae (Bk). Clarification of the diagnostic utility of IFA serology when testing against these organisms is needed.

OBJECTIVE

To evaluate the specificity of Bartonella IFA assays utilizing 6 cell culture-grown antigen preparations.

ANIMALS

Archived sera from SPF dogs (n = 29) and from dogs experimentally infected with Bvb (n = 10) and Bh (n = 3).

METHODS

Antibodies (Abs) to Bvb genotypes I, II, and III, Bh serotype I, strains H-1 and SA2, and to Bk were determined by IFA testing.

RESULTS

Serum from naïve SPF dogs shown to be negative for Bartonella bacteremia did not react with any of the 6 Bartonella antigens by IFA testing. Dogs experimentally infected with Bvb genotype I developed Abs against homologous antigens, with no cross-reactivity to heterologous Bvb genotypes, Bh H-1, SA2 strains, or to Bk. Dogs experimentally infected with Bh serotype I developed Abs against Bh H-1, but not to Bh SA2 strain with no cross-reactive Abs to Bvb genotypes I-III or to Bk.

CONCLUSIONS AND CLINICAL IMPORTANCE

Bartonella spp. Ab responses during acute experimental infections are species and type specific.

Erratum: 2013 AAFP Feline Vaccination Advisory Panel Report

Regrettably, an error appeared in the ‘Injectable vaccine administration’ box on page 798: the pictures in Figures 8 and 9 were swapped with each other. ( The error appears in the printed copies of the journal, and in online versions downloaded before mid-October 2013.) The amended box is reproduced here in full.

DOI of original article: 10.1177/1098612X13500429

Efficacy of intranasal administration of a modified live feline herpesvirus 1 and feline calicivirus vaccine against disease caused by Bordetella bronchiseptica after experimental challenge

BACKGROUND

Studies suggest that intranasal vaccination can stimulate nonspecific immunity against agents not contained within the vaccine, but this effect is not reported for cats.

HYPOTHESIS

A modified live feline herpesvirus-1 (FHV-1) and feline calicivirus (FCV) intranasal vaccine will reduce clinical signs of disease caused by experimental infection with Bordetella bronchiseptica.

ANIMALS

Twenty specific pathogen-free 12-week-old kittens.

METHODS

Experimental study. Cats were randomized into 2 groups of 10 cats each. The vaccinated group was administered a single intranasal dose of a commercially available vaccine containing modified live strains of FHV-1 and FCV, and the control group remained unvaccinated. All 20 cats were administered B. bronchiseptica by nasal inoculation 7 days later and were observed daily for clinical signs of illness for 20 days.

RESULTS

In the first 10 days after B. bronchiseptica challenge, vaccinated cats were less likely to be clinically ill than control cats with a median clinical score of 0/180 (range 0-5) versus 2/180 (range 0-8) (P = .01). Nine of 10 control cats and 2 of 10 vaccinated cats were recorded as sneezing during days 1-10 after challenge (P = .006).

CONCLUSIONS AND CLINICAL IMPORTANCE

Intranasal vaccination against FHV-1 and FCV decreased signs of illness due to an infectious agent not contained in the vaccine. This nonspecific immunity could be beneficial for protection against organisms for which vaccines are not available and as protection before development of vaccine-induced humoral immunity.

Prevalence of Bartonella species, hemoplasmas, and Rickettsia felis DNA in blood and fleas of cats in Bangkok, Thailand

Flea infestations are common in Thailand, but little is known about the flea-borne infections. Fifty flea pools and 153 blood samples were collected from client-owned cats between June and August 2009 from veterinary hospitals in Bangkok, Thailand. Total DNA was extracted from all samples, and then assessed by conventional PCR assays. The prevalence rates of Bartonella spp. in blood and flea samples were 17% and 32%, respectively, with DNA of Bartonella henselae and Bartonella clarridgeiae being amplified most commonly. Bartonella koehlerae DNA was amplified for the first time in Thailand. Hemoplasma DNA was amplified from 23% and 34% of blood samples and flea pools, respectively, with 'Candidatus Mycoplasma haemominutum' and Mycoplasma haemofelis being detected most frequently. All samples were negative for Rickettsia felis. Prevalence rate of B. henselae DNA was increased 6.9 times in cats with flea infestation. Cats administered flea control products were 4.2 times less likely to be Bartonella-infected.

Severe myositis associated with Sarcocystis spp. infection in 2 dogs

BACKGROUND

Dogs are definitive hosts for numerous species of the intracellular protozoan parasite Sarcocystis. Reports of sarcocysts in muscles of dogs most often represent incidental findings.

HYPOTHESIS/OBJECTIVES

To report the clinicopathologic, ultrastructural, and molecular findings in 2 dogs with myositis associated with Sarcocystis spp. infection, as well as the response to treatment with antiprotozoal drugs.

ANIMALS

Two dogs with severe myositis in association with massive sarcocystosis.

METHODS

Retrospective case review. Affected dogs were identified by a diagnostic laboratory. Attending clinicians were contacted, and the medical records reviewed. Immunostaining and electron microscopy were performed on muscle biopsies. Biopsies also were subjected to 18S rRNA gene PCR.

RESULTS

Both dogs had fever, lymphopenia, thrombocytopenia, and increased serum alanine aminotransferase (ALT) activity when first evaluated. One dog developed hyperbilirubinemia. Subsequently, both dogs had increased serum creatine kinase activity and clinical signs of myositis, with reluctance to move, generalized pain, and muscle wasting. Histopathology of muscle biopsies showed severe inflammatory and necrotizing myopathy with numerous sarcocysts. Ultrastructural studies and 18S rRNA gene sequence results were consistent with infection with a Sarcocystis spp. other than Sarcocystis neurona. Both dogs initially were treated unsuccessfully with clindamycin and anti-inflammatory drugs. One dog died. The other dog subsequently responded to treatment with decoquinate.

CONCLUSIONS AND CLINICAL IMPORTANCE

Sarcocystis spp. infection should be included in the differential diagnosis for dogs that develop fever, thrombocytopenia, increased liver enzyme activities, and clinical and biochemical evidence of myositis. Although additional studies are required, decoquinate holds promise as an effective treatment for the disease.

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.

Effect of the probiotic Enterococcus faecium SF68 on presence of diarrhea in cats and dogs housed in an animal shelter

BACKGROUND

Beneficial effects of probiotics have never been analyzed in an animal shelter.

HYPOTHESIS

Dogs and cats housed in an animal shelter and administered a probiotic are less likely to have diarrhea of ≥2 days duration than untreated controls.

ANIMALS

Two hundred and seventeen cats and 182 dogs.

METHODS

Double blinded and placebo controlled. Shelter dogs and cats were housed in 2 separate rooms for each species. For 4 weeks, animals in 1 room for each species was fed Enterococcus faecium SF68 while animals in the other room were fed a placebo. After a 1-week washout period, the treatments by room were switched and the study continued an additional 4 weeks. A standardized fecal score system was applied to feces from each animal every day by a blinded individual. Feces of animals with and without diarrhea were evaluated for enteric parasites. Data were analyzed by a generalized linear mixed model using a binomial distribution with treatment being a fixed effect and the room being a random effect.

RESULTS

The percentage of cats with diarrhea ≥2 days was significantly lower (P = .0297) in the probiotic group (7.4%) when compared with the placebo group (20.7%). Statistical differences between groups of dogs were not detected but diarrhea was uncommon in both groups of dogs during the study.

CONCLUSION AND CLINICAL IMPORTANCE

Cats fed SF68 had fewer episodes of diarrhea of ≥2 days when compared with controls suggests the probiotic may have beneficial effects on the gastrointestinal tract.

Associations among albuminuria, C-reactive protein concentrations, survival predictor index scores, and survival in 78 critically ill dogs

BACKGROUND

Microalbuminuria and C-reactive protein (CRP) are predictors of morbidity and survival in critically ill human patients.

HYPOTHESIS/OBJECTIVES

To evaluate results of microalbuminuria assays (untimed single-sample urine albumin concentration [U-ALB] and the urine albumin:creatinine ratio [UACR]), serum CRP, and survival predictor index (SPI2) scores as predictors of survival in critically ill dogs.

ANIMALS

Seventy-eight dogs admitted to intensive care units at University of Tennessee (UT) and Colorado State University (CSU).

METHODS

Prospective observational study. Critically ill dogs were eligible for enrollment, unless euthanized because of financial constraints. Samples were collected within 3 hours of admission. Spearman's rank-correlation coefficients were determined for U-ALB, UACR, CRP, and SPI2. U-ALB, UACR, CRP, and SPI2 were assessed for associations with 7- and 30-day survival by Mann-Whitney U-tests and receiver operating characteristic (ROC) curves. P-values < .0125 were considered significant.

RESULTS

UT (n = 49) and CSU (n = 29) patients did not differ significantly. Forty percent (31/78) of dogs died. SPI2 was inversely correlated with U-ALB (r(s) = -0.39, P < .001) and UACR (r(s) = -0.41, P < .001). CRP was not correlated with SPI2 (P = .019), U-ALB (P > .1), or UACR (P > .1). U-ALB and UACR had very high correlation (r(s) = 0.95, P < .001). SPI2, U-ALB, and UACR differed significantly for survivors and nonsurvivors. SPI2, U-ALB, and UACR had areas under the ROC curve (AUC) from 0.68 to 0.74 for survival prediction.

CONCLUSIONS AND CLINICAL IMPORTANCE

Albuminuria and SPI2, but not CRP, are associated with survival in critically ill dogs. Suboptimal AUCs limit the value of microalbuminuria testing for clinical risk assessment. Additional studies are necessary to determine the usefulness of microalbuminuria testing in patient risk stratification for prospective research.

Variability in results of the microscopic agglutination test in dogs with clinical leptospirosis and dogs vaccinated against leptospirosis

Background: The microscopic agglutination test (MAT) is commonly used for the diagnosis of canine leptospirosis. In dogs it is sometimes suggested that the serogroup with the highest MAT titer is the infecting serogroup; however, this is not true in humans with confirmed leptospirosis. We sought to investigate the value of MAT results in predicting the infecting serogroup by comparing results across several laboratories and within individual dogs over time.

Objectives: To examine the variability in MAT results across different laboratories in dogs recently vaccinated against leptospirosis, and in dogs with clinical leptospirosis, and to investigate variability over time in MAT results in individual dogs with leptospirosis.

Animals: Eighteen dogs from a research colony, 9 of which had been vaccinated against leptospirosis, and 17 dogs clinically diagnosed with leptospirosis.

Methods: Serum samples were submitted to up to 5 veterinary diagnostic laboratories for MAT titers from each dog on at least 1 occasion. MAT results also were followed over time in 6 dogs diagnosed with leptospirosis.

Results: MAT results were discordant across different laboratories in dogs recently vaccinated against leptospirosis and in dogs with clinical leptospirosis. MAT results varied over time in individual dogs with the disease.

Conclusions and Clinical Importance: The MAT is a valuable test for the diagnosis of leptospirosis in dogs, but it is unlikely that test results can be used to predict the infecting serogroup. Laboratories offering the MAT should consider participation in a proficiency scheme.

Antibodies against Crandell Rees feline kidney (CRFK) cell line antigens, alpha-enolase, and annexin A2 in vaccinated and CRFK hyperinoculated cats

BACKGROUND

Cats inoculated with feline herpesvirus 1, calicivirus, and panleukopenia (FVRCP) vaccines grown on the Crandell Rees feline kidney (CRFK) cell line have been shown to develop anti-CRFK antibodies. The identities of common CRFK antigens are unknown.

HYPOTHESIS

Cats inoculated with CRFK lysates and FVRCP vaccines will develop autoantibodies measurable by Western blot immunoassay. Antigens associated with these antibodies can be isolated for further study.

ANIMALS

One CRFK hyperinoculated rabbit, 44 age-matched unvaccinated kittens purchased from a commercial vendor.

METHODS

Commonly recognized CRFK antigens were identified by comparison of Western blot immunoassays using sera from a hyperinoculated rabbit and kittens inoculated with CRFK lysate or 1 of 4 commercially available FVRCP vaccines. Antigens were purified from CRFK lysates and sequenced. Antigen recognition was confirmed by Western blot immunoassay and indirect ELISA for 2 proteins using sera from CRFK and FVRCP inoculated kittens.

RESULTS

CRFK antigens 47, 40, and 38 kD in size were identified. Protein isolation and sequencing identified 3 CRFK proteins as alpha-enolase, annexin A2, and macrophage capping protein (MCP). Sera from FVRCP and CRFK inoculated cats were confirmed to recognize annexin A2 and alpha-enolase by Western blot immunoassay and indirect ELISA.

CONCLUSIONS AND CLINICAL RELEVANCE

This study validated the use of Western blot immunoassay for detection of antibodies against CRFK proteins and identified 3 CRFK antigens. In humans, alpha-enolase antibodies are nephritogenic; alpha-enolase and annexin A2 antibodies have been associated with autoimmune diseases. Further research will be necessary to determine the clinical relevance of these findings.

Seroprevalence of Toxoplasma gondii and Bartonella spp. antibodies in cats from Pennsylvania

Toxoplasma gondii and Bartonella spp. are zoonotic pathogens of cats. In the present study, the prevalence of antibodies to T. gondii and Bartonella spp. were determined in sera from 210 domestic cats from Bensalem, Pennsylvania. Using a modified agglutination test, antibodies to T. gondii were found in 41 (19.5%) of the 210 cats with titers of 1:25 in 4, 1:50 in 9, 1:100 in 7, 1:200 in 3, 1:400 in 3, 1:800 in 5, 1:1,600 in 4, and 1:3,200 or higher in 6. For T. gondii, seroprevalence increased with age of the cat: 15 of 113 (13.2 %) were seropositive compared with 26 of 97 (26.7%) older than 11 mo. Of these 210 cats, 54 (25.7%) were positive for Bartonella spp. antibodies, with titers of 1:64 in 20, 1:128 in 21, 1:256 in 9, and 1:512 in 4. Seventeen cats had antibodies to both organisms. There was no correlation between T. gondii and Bartonella spp. seropositivity. Overall the seroprevalence of T. gondii antibodies in cats in this population is much lower compared with those reported in other localities in the United States and other countries.

Efficacy of pradofloxacin in cats with feline upper respiratory tract disease due to Chlamydophila felis or Mycoplasma infections

BACKGROUND

Upper respiratory tract disease (URTD) of cats is caused by a number of pathogens, including Chlamydophila felis and Mycoplasma spp. For effective treatment of both infections, doxycycline and enrofloxacin are recommended, but adverse effects limit their use in cats.

HYPOTHESIS

That the fluoroquinolone pradofloxacin is effective against C. felis and Mycoplasma infection in cats with URTD or conjunctivitis.

ANIMALS

Thirty-nine cats with signs of URTD or conjunctivitis.

METHODS

Placebo-controlled, double-blind clinical trial. Cats were randomly entered into 1 of 2 treatment groups: treated PO with either 5 mg/kg pradofloxacin q24h or 5 mg/kg doxycycline q12h for 42 consecutive days. Changes in health status and clinical scores were evaluated. The presence of C. felis and Mycoplasma spp. was determined by quantitative polymerase chain reaction (PCR) and nested PCR of conjunctival swabs, respectively.

RESULTS

At the beginning of the study, C. felis and Mycoplasma spp. were detected in 23 and 20 cats, respectively. Cats of both groups responded rapidly with a marked improvement in clinical signs within the 1st week. During treatment with either drug, C. felis DNA copy number declined quickly. Complete elimination of Mycoplasma spp. was achieved in both groups; however, whereas all cats receiving doxycycline eliminated C. felis, 4 cats treated with pradofloxacin remained PCR-positive.

CONCLUSION AND CLINICAL IMPORTANCE

This study demonstrates that both pradofloxacin and doxycycline have good efficacy against C. felis and Mycoplasma spp., resulting in a marked improvement of clinical signs. However, C. felis DNA remained in some cats after treatment with pradofloxacin, suggesting that infection might not have been eliminated.

Infectious diseases of dogs and cats on Isabela Island, Galapagos

Background: Vaccination and importation of dogs and cats are prohibited in the Galapagos, resulting in a uniquely isolated population. The purpose of this study was to determine the prevalence of infectious diseases of dogs and cats that impact their health, could spill over to native wildlife, or sentinel diseases of concern to humans.

Hypothesis: The isolation of dogs and cats in the Galapagos protects them from diseases common in mainland populations.

Animals: Ninety‐five dogs and 52 cats presented during a neutering campaign.

Methods: A prospective cross‐sectional study was performed. Blood was collected for serological and DNA evaluation of a panel of infectious diseases.

Results: Antibodies against parvovirus (100%), parainfluenza virus (100%), adenovirus 1/2 (66–67%), and distemper virus (22%) were present in dogs. Dirofilaria immitis was also common in dogs (34%), with lower prevalences of Wolbachia pipiens (22%), Bartonella sp. (13%), Ehrlichia/Anaplasma spp. (1%), and Mycoplasma haemocanis (1%) observed. Antibodies against panleukopenia virus (67%), Toxoplasma gondii (63%), calicivirus (44%), and herpesvirus 1 (10%) were detected in cats. Feline leukemia virus antigen, feline immunodeficiency virus antibody, or coronavirus antibodies were not detected. Bartonella sp. (44%) infections were common in cats, but only one was infected with M. haemofelis.

Conclusions and Clinical Importance: Despite their relative seclusion from the rest of the world, cats and dogs of Isabela were exposed to many pathogens found in mainland South America. Parasite prophylaxis, neutering, and strict enforcement of animal movement restrictions would control a majority of the diseases. In the absence of vaccination, a reservoir of susceptible animals remains vulnerable to new disease introductions.

Delayed recurrence of nasal aspergillosis in a dog

A two-year-old, female spayed Australian cattle dog was diagnosed with nasal aspergillosis. The dog was treated topically with clotrimazole. Clinical signs recurred two months later and the clotrimazole treatment was repeated and 5 mg/kg itraconazole twice daily was added to it. The recommended dose of itraconazole for nasal aspergillosis is 5 mg/kg twice daily administered orally. The dog's symptoms completely resolved, but it developed an adverse febrile reaction to the Itraconazole. The Itraconazole was discontinued and the dog remained asymptomatic for four years. The dog then developed mucopurulent discharge from the right nostril and was diagnosed as having recurrent nasal aspergillosis. Itraconazole at 5 mg/kg twice daily was prescribed, which again induced a fever. When the itraconazole was decreased to 5 mg/kg once daily there were no fever episodes, but the nasal discharge was not completely resolved. The dog was then treated with topical clotrimazole Infusion, and maintained on 5 mg/kg itraconazole daily. To the authors' knowledge, this case is unique because of the delayed recurrence of nasal aspergillosis. Additionally, the idiosyncratic febrile reaction to the itraconazole has not previously been reported in the veterinary literature, but is similar to reports of drug-induced fever in humans.

Polymerase chain reaction for the detection of Cryptosporidium spp. in cat feces

The objective of this study was to compare a polymerase chain reaction (PCR) assay and a monoclonal antibody-based immunofluorescence assay (IFA) for detection of Cryptosporidium parvum in cat feces. Eight C. parvum-naive DSH cats were orally inoculated with 1 x 10(6) oocysts of a C. parvum human isolate. Fecal samples were collected before inoculation, daily for the next 30 days, and twice weekly until day 85. Methylprednisolone acetate was administered at 20 mg/kg i.m. on days 85, 92, and 99. From days 86 to 115, feces were collected daily and then up to twice weekly until day 126. Immunofluorescence assay was performed after collection of the samples, and then the samples were frozen at -70 C until assayed by PCR. Cryptosporidium parvum was detected by PCR in 101 of 353 samples and by IFA in 52 of 353 samples: 27 samples were PCR positive, IFA positive; 74 samples were PCR positive, IFA negative; 25 samples were PCR negative, IFA positive; and 227 samples were PCR negative, IFA negative. The percentage of concordance between IFA and PCR was 72%. Results of this study suggest that this PCR assay is more sensitive than IFA for detection of C. parvum in cat feces.

Use of a PCR assay to assess the prevalence and risk factors for Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum' in cats in the United Kingdom

Blood samples from 426 healthy and sick cats in the UK were tested in a PCR assay for 'Candidatus Mycoplasma haemominutum' and Mycoplasma haemofelis (basonym Haemobartonella felis). Seventy-two of the cats (16.9 per cent) were positive for 'Candidatus M. haemominutum' alone, six (1.4 per cent) were positive for M. haemofelis alone and one (0.2 per cent) was positive for both. Logistic regression analysis indicated that older male cats were significantly more likely to be infected with 'Candidatus M. haemominutum', but there was no significant association between it and any of the haematological variables measured. M. haemofelis infection was uncommon in the anaemic cats sampled, and there were too few positive cases for multivariable analysis to be performed for M. haemofelis-positive status.

Feline inflammatory polyps: historical, clinical, and PCR findings for feline calici virus and feline herpes virus-1 in 28 cases

Inflammatory polyps are associated with significant aural or nasopharyngeal disease in cats. It has been proposed that chronic viral infection may induce the masses. Ventral bulla osteotomy (VBO) is usually recommended for definitive therapy but removal of masses from the nasopharynx or external ear canal by traction/avulsion is also used. A retrospective study of 28 cats with inflammatory polyps was conducted to correlate recurrence with mode of therapy. Tissues from 41 polyps were assayed for feline calicivirus and feline herpesvirus-1 by RT-PCR and PCR, respectively. Of the 14 cats initially treated by traction/avulsion, recurrence was detected in five of nine cats with radiographic evidence of bulla disease but none of the cats with normal bullae. Traction/avulsion is a reasonable treatment for inflammatory polyps if the bullae are radiographically normal. Failure to detect feline calicivirus and feline herpesvirus-1 suggests that tissue persistence of these viruses is not associated with the development of inflammatory polyps.

Inoculation with Bartonella henselae followed by feline herpesvirus 1 fails to activate ocular toxoplasmosis in chronically infected cats

Infection by Toxoplasma gondii is very common in cats although most remain disease free. The factors that trigger development of uveitis in some cats infected with T gondii have not been elucidated, but infection by more than one organism may be contributory. In this study, cats chronically infected with T gondii were inoculated with Bartonella henselae followed by FHV-1 to test the hypothesis that immune stimulation by multiple infections will reactivate ocular toxoplasmosis. Anterior uveitis and chorioretinitis were not detected in the cats with chronic T gondii infection thus allowing rejection of the hypothesis using this experimental design.

Haemobartonella felis: recent developments in diagnosis and treatment

Haemobartonella felis is a pleomorphic uncultivated wall-less haemotrophic bacterial parasite. Phylogenetic analysis of 16S rRNA gene sequences from a number of isolates of H felis has demonstrated that these bacteria are most closely related to species in the genus Mycoplasma, and Haemobartonella and related organisms are currently being reclassified as Mollicutes. Diagnosis by cytological examination of blood smears has been problematic, but recent molecular studies have led to the development of sensitive polymerase chain reaction (PCR) assays for diagnosis. Such studies have also resulted in the recognition of two distinct strains of H felis, which are divided into different groups based on phylogenetic analysis. This evolutionary divergence between strains is accompanied by differences in pathogenecity. This review discusses new developments in the diagnosis and treatment of H felis, focusing on the use of, and interpretation of, PCR assays.

Detection of Toxoplasma gondii in the milk of experimentally infected lactating cats

Tachyzoites of Toxoplasma gondii have been found in the milk of sheep, goats, cows and mice and infection by ingestion of raw goat milk has been documented in humans. Lactational transmission from infected cats to their kittens is suspected but the organism has not been detected in the milk. The purpose of this study was to demonstrate the presence of T. gondii in the milk of experimentally infected cats. Pregnant specific pathogen free cats were inoculated orally with T. gondii at various times prior to parturition. Feces were examined for oocyst shedding after sugar solution centrifugation. Milk was collected for polymerase chain reaction (PCR) and bioassay in mice. T. gondii was detected in the milk of five of six cats by either bioassay or PCR.

Clinical ocular toxoplasmosis in neonatal kittens

OBJECTIVE

To describe ocular findings in kittens with congenital or early neonatal infection by Toxoplasma gondii and to determine if there are detectable differences in disease caused by three strains.

ANIMALS STUDIED

Six adult female cats and the offspring from seven litters.

METHODS

Four kittens from uninfected specific pathogen-free (SPF) queens and 21 kittens from SPF queens inoculated at various times late in gestation with Mozart, Maggie, or ME-49 strain of T. gondii were used. Ocular examinations were performed on queens prior to and after delivery, and on kittens weekly to bi-weekly for up to 27 weeks. Whole blood for serology was collected from all kittens at 5(1/2) to 8 weeks of age and again at 12 weeks of age or later.

RESULTS

No kittens from noninfected queens developed ocular lesions or antibody to T. gondii. Three of the 24 kittens from infected queens died or were euthanized early in the study. Chorioretinitis was detected in 15 of 21 living kittens from infected queens. Two developed concurrent anterior uveitis that resolved within 1 week. Posterior segment lesions varied ophthalmoscopically between strains. Of 21 kittens from T. gondii-infected queens, six developed positive antibody titers to T. gondii during the study. All seropositive kittens were born to queens infected with Mozart strain of T. gondii.

CONCLUSION

Results of this study suggest that ocular toxoplasmosis can occur without other evidence of clinical illness in kittens infected in utero or in the neonatal period, and that T. gondii strains may have varying degrees of ocular pathogenicity in cats.

Inoculation of two genotypes of Hemobartonella felis (California and Ohio variants) to induce infection in cats and the response to treatment with azithromycin

OBJECTIVES

To describe clinical and laboratory findings associated with cats experimentally infected by inoculation with the 2 recognized genotypes of Hemobartonella felis (small variant, Hfsm; large variant, Hflg) and to determine the response of cats to treatment with azithromycin.

ANIMALS

18 young adult domestic shorthair cats of both sexes.

PROCEDURES

Cats were inoculated with H felis and monitored weekly, using CBC counts and a polymerase chain reaction (PCR) designed to detect both genetic variants of H felis. Beginning 26 days after inoculation, 11 cats were administered azithromycin (15 mg/kg of body weight, PO, q 12 h, for 7 days).

RESULTS

Inoculation resulted in coinfection with Hflg and Hfsm, and both variants were detected by PCR. Clinical abnormalities and anemia were most severe in Hflg- and dual-infected cats. Results of PCR and CBC were positive for H felis in 112/112 (100%) and 42/112 (37.5%), respectively, samples collected after inoculation. Administration of azithromycin had little effect on clinical variables, including anemia. All cats, regardless of treatment with azithromycin, had positive results for the PCR at the end of the study period.

CONCLUSIONS AND CLINICAL RELEVANCE

In these cats, Hflg was more pathogenic than Hfsm, and coinfection with both variants was detected. Results of the PCR were superior to results of CBC for detecting infection with H felis. Azithromycin administered at the dose and duration reported here was not efficacious for the treatment of cats with hemobartonellosis.

Use of a polymerase chain reaction assay to detect and differentiate two strains of Haemobartonella felis in naturally infected cats

OBJECTIVE

To develop a polymerase chain reaction (PCR) assay that detects and differentiates the Ohio strain of Haemobartonella felis (H. felis-OH) and the California strain of H. felis (H. felis-CA) and to apply the assay to blood samples from cats with and without suspected haemobartonellosis (suspect and control cats, respectively).

SAMPLE POPULATION

220 blood samples were examined; 82 were from suspect cats, and 138 were from control cats.

PROCEDURE

A PCR assay was designed to detect and differentiate H. felis-OH and H. felis-CA.

RESULTS

On the basis of PCR assay results, the overall prevalence of H. felis infection was 19.5% (43/220). Suspect cats (28.0%; 23/82) were significantly more likely than control cats (14.5%; 20/138) to be H. felis infected. Significantly greater numbers of suspect cats were H. felis-OH infected (12.2%, 9/82) or H. felis-OH and H. felis-CA infected (4.9%, 4/82) than control cats (0% [0/138] and 0.7% [1/138], respectively). Significantly more anemic cats were H. felis-OH infected (14.3%; 4/28) or H. felis-OH and H. felis-CA infected (7.1%; 2/28) than nonanemic cats (2.3% [3/128] and 0.8% [1/128], respectively). The PCR assay was more accurate than cytologic examination for detection of H. felis.

CONCLUSIONS AND CLINICAL RELEVANCE

Haemobartonella felis infections are more common in cats than previously recognized. Haemobartonella felis-OH is apparently more pathogenic than H. felis-CA. The PCR assay is more accurate than cytologic examination for detection of H. felis infection and is an effective clinical tool for the detection and differentiation of both H. felis strains known to infect cats.

Effect of a bioflavonoid dietary supplement on acetaminophen-induced oxidative injury to feline erythrocytes

OBJECTIVE

To determine the effect of a commercial bioflavonoid antioxidant on acetaminophen-induced oxidative injury to feline erythrocytes.

DESIGN

Randomized controlled study.

ANIMALS

45 healthy age-matched cats.

PROCEDURE

Cats were assigned to 3 experimental groups. Groups 1 and 3 received a bioflavonoid antioxidant (10 mg/d) orally for 2 weeks. Groups 2 and 3 received an oxidative challenge with acetaminophen (90 mg/kg [41 mg/lb] of body weight, PO) on day 7. Packed cell volume, percentage of erythrocytes with Heinz bodies, blood methemoglobin concentration, and blood reduced and oxidized glutathione concentrations were determined at various times during the 2-week study period.

RESULTS

Adverse effects were not associated with bioflavonoid antioxidant administration alone. Acetaminophen administration resulted in a significant increase in methemoglobin concentration in groups 2 and 3; differences were not detected between these groups. Heinz body concentrations in groups 2 and 3 increased after acetaminophen administration; however, the increase in cats that received the antioxidant was significantly less than in group-2 cats. Total blood glutathione concentrations did not change significantly in groups 2 and 3 after acetaminophen administration; however, ratio of reduced to oxidized glutathione concentration increased significantly after administration in group-2 cats, compared with group-3 cats.

CONCLUSIONS AND CLINICAL RELEVANCE

Oral administration of bioflavonoid antioxidants to cats at risk for oxidative stress may have a beneficial effect on their ability to resist oxidative injury to erythrocytes.

Prevalence of enteric zoonotic organisms in cats

OBJECTIVE

To determine prevalence of enteric zoonotic organisms in cats in north-central Colorado.

DESIGN

Prospective study.

SAMPLE POPULATION

Serum and fecal samples from 87 cats with diarrhea, 106 cats without diarrhea, and 12 cats for which fecal consistency was unknown.

PROCEDURES

Samples were obtained from client-owned cats and cats at a humane society shelter. Serum was assayed for feline leukemia virus antigen and antibodies against feline immunodeficiency virus, IgM antibodies against Toxoplasma gondii, and IgG antibodies against T gondii and Cryptosporidium parvum. Microscopic examination of unstained feces was performed after centrifugation in a zinc sulfate solution, thin fecal smears were stained with acid fast stain and examined for C parvum, and bacteriologic culture of feces was used to detect aerobic and anaerobic bacteria.

RESULTS

Enteric zoonotic organisms were detected in feces from 27 of 206 (13.1%) cats and included C parvum (5.4%), Giardia spp (2.4%). Toxocara cati (3.9%), Salmonella enterica serotype Typhimurium (1.0%), and Campylobacter jejuni (1.0%); each organism was detected in samples from cats with and without diarrhea. Although differences between groups were not significant, a higher proportion of shelter cats (18.2%) had enteric zoonotic organisms than client-owned cats (10.1%).

CONCLUSIONS AND CLINICAL RELEVANCE

Enteric zoonotic organisms were detected in feces of 13.1% of cats, suggesting that cats, particularly those in homes of immunocompromised humans, should be evaluated for enteric zoonotic organisms.

Bartonella spp antibodies and DNA in aqueous humour of cats

Bartonella spp antibodies were measured in the serum and aqueous humour of cats with and without uveitis and polymerase chain reaction (PCR) for Bartonella spp DNA was performed on aqueous humour from most of the cats. Serum and aqueous humour were assayed from 49 client-owned cats with uveitis, 49 healthy shelter cats, and nine cats experimentally inoculated with either B henselae or B clarridgeiae, 454 days after inoculation. An aqueous antibody coefficient (C value) was calculated for cats positive for Bartonella spp antibodies in the aqueous humour. Ocular production of Bartonella spp IgG (C value >1) was detected in seven of 49 cats with uveitis, none of 49 healthy shelter cats, and four of nine experimentally inoculated cats. The organism was detected by PCR in the aqueous humour of three of 24 cats with uveitis, one of 49 healthy shelter cats, and four of nine experimentally inoculated cats. Bartonella spp infect the eyes of some cats following natural exposure or experimental inoculation and may cause uveitis in some cats.

Functional urethral obstruction in 3 dogs: clinical and urethral pressure profile findings

Three dogs with dysuria and urine retention caused by excessive functional urethral resistance are described. All dogs had clinical histories and urologic signs that previously would have been classified as detrusor-urethral dyssynergia. Diagnosis of functional urinary obstruction was established by exclusion of anatomic urinary obstruction and confirmed by urethral pressure profilometry. In 2 cases, multiple pressure deflections recorded in the urethral pressure profile suggested spasm of urethral musculature, whereas in a 3rd dog, abnormally high pressures were recorded along a portion of the proximal urethra. Functional urinary obstruction was associated with prostatitis in 1 dog and with a history of urethral calculi in 1 dog, and no underlying disorder could be identified in the remaining dog. All 3 dogs improved with medical treatments that included alpha adrenergic antagonists. The etiology, diagnosis, and pharmacologic management of functional urinary obstruction are discussed.

Detection of Toxoplasma gondii parasitemia in experimentally inoculated cats

Toxoplasma gondii B1 gene polymerase chain reaction (PCR) amplification utilizing a flanking and nesting reaction was compared to mouse bioassay on feline whole blood samples collected before and after experimental inoculation with T. gondii. Samples were collected from 5 cats prior to inoculation with T. gondii and on days 3, 7, 10, 14, 21, 28, 35, 42, 49, 56, 63, 70, 84, 112, 140, 143, 147, 150, 154, 161, 168, 175, and 182 after inoculation. Cats were challenged with T. gondii orally on day 140. Bioassay was found to be less effective for detection of parasitemia than B1 gene PCR. Parasitemia was detected in all 5 cats by PCR multiple times after primary and challenge inoculation. Detection of T. gondii parasitemia by PCR utilizing the flanking reaction described here may be useful in predicting the oocyst shedding period in individual cats. As none of the cats developed signs of systemic illness, yet were chronically parasitemic, T. gondii whole-blood PCR is not helpful as a diagnostic test for clinical feline toxoplasmosis.

Detection of feline herpesvirus-specific antibodies and DNA in aqueous humor from cats with or without uveitis

OBJECTIVE

To determine whether uveitis in cats was associated with intraocular production of feline herpesvirus type 1 (FHV-1)-specific antibodies or with detection of FHV-1 DNA in aqueous humor (AH).

ANIMALS

44 cats with idiopathic uveitis, 29 cats with uveitis attributed to Toxoplasma gondii infection, 13 FHV-1 seropositive cats without uveitis, and 9 FHV-1 seronegative cats without uveitis.

PROCEDURE

ELISA were used to detect FHV-1-specific antibodies and total IgG antibodies in serum and AH, and the Goldmann-Witmer coefficient (C-value) for intraocular antibody production was calculated. A polymerase chain reaction assay was used to detect FHV-1 DNA in AH.

RESULTS

FHV-1 seroprevalence among cats with uveitis was not significantly different from seroprevalence among cats without uveitis. Intraocular FHV-1 antibodies were never detected in cats without uveitis. Significantly more cats with idiopathic uveitis (22/44) or with toxoplasmic uveitis (11/29) had evidence of intraocular antibody production (C-value > 1) than did cats without uveitis. Only cats with idiopathic uveitis had FHV-1 C-values > 8. Among cats with evidence of intraocular antibody production, cats with idiopathic uveitis had a significantly higher median FHV-1 C-value (9.61) than did cats with toxoplasmic uveitis (2.56). Overall, FHV-1 DNA was detected in AH from 12 cats, 11 of which had uveitis.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that FHV-1 can infect intraocular tissues of cats and that intraocular FHV-1 infection may be associated with uveal inflammation in some cats.

Pulmonary thromboembolism in 29 dogs: 1985-1995

Pulmonary thromboembolism (PTE) occurs as a complication to a number of commonly encountered clinical diseases. Antemortem recognition of this life-threatening disorder is hampered by nonspecificity of clinical signs. This retrospective study was performed to analyze clinical features, laboratory findings, imaging abnormalities, and concurrent postmortem diagnoses in 29 dogs with confirmed pulmonary embolism. A variety of clinicopathologic and radiographic abnormalities were noted but there were no pathognomonic findings for PTE. Arterial blood gas analyses were performed in 15 (52%) of 29 dogs; 12 (80%) of 15 exhibited hypoxemia and 15 (100%) of 15 had increased alveolar-arterial oxygen gradients. Response to supplemental O2 was variable and did not correlate with the presence or absence of additional pulmonary pathology on postmortem. At postmortem, 25 (86%) of 29 dogs had grossly visible emboli, 17 (59%) of 29 dogs had multiple disease processes, and 16 (55%) of 29 dogs had additional pulmonary pathology. PTE was suspected antemortem in 11 (38%) of 29 dogs. In dogs with respiratory signs consistent with PTE, the condition was a differential diagnosis in 11 of 17 animals; all had diseases previously reported to be associated with PTE. Neoplasia, systemic bacterial disease, and immune-mediated hemolytic anemia were diagnosed most frequently.

Bartonella spp infection as a possible cause of uveitis in a cat

A 6-year-old castrated mixed-breed cat was evaluated because of unilateral anterior uveitis. The cat was seronegative for antibodies to Toxoplasma gondii, coronaviruses, and feline immunodeficiency virus, and antigens for FeLV p27 and Cryptococcus neoformans. Antibodies to Bartonella spp were detected in serum and aqueous humor. The antibody coefficient (C value) for IgG antibodies to Bartonella spp in the aqueous humor was 4.42; values > 1 suggest ocular production of antibodies and supports a diagnosis of ocular infection. Topical administration of prednisolone and oral administration of prednisone failed to induce a response; however, the uveitis resolved rapidly after the cat was given doxycycline orally. Clinical or laboratory evidence of immunodeficiency in this cat was not detected. Detection of a serum IgG antibody titer to Bartonella spp and ocular production of IgG antibodies to Bartonella spp, exclusion of other causes of uveitis, and response to doxycycline suggests that the cat may have had bartonellosis resulting in uveal tract inflammation.

Evaluation of serologic and viral detection methods for diagnosing feline herpesvirus-1 infection in cats with acute respiratory tract or chronic ocular disease

OBJECTIVE

To determine the value of virus isolation (VI), immunofluorescent antibody (IFA) assay, serum neutralization (SN), and ELISA for the diagnosis of clinical feline herpesvirus-1 (FHV-1) infection in cats.

ANIMALS

46 clinically normal cats, 17 cats with signs of acute respiratory tract disease, and 38 cats with signs of chronic ocular disease.

PROCEDURE

Conjunctival swabs for VI, conjunctival scrapings for IFA testing, and venous blood samples for SN or ELISA testing were obtained from all cats.

RESULTS

FHV-1 was detected in 10.9 and 28.3% of clinically normal cats and in 18.2 and 33.3% of cats with FHV-1-associated disease by VI and the IFA assay, respectively. There were no significant differences in the viral detection rate between cats with acute respiratory tract disease and cats with chronic ocular disease or between diseased cats and clinically normal cats; however, FHV-1 was never detected by both methods in clinically normal cats. Overall FHV-1 seroprevalence was 97% when tested by ELISA and 66% when tested by SN. Seroprevalence did not vary significantly among the 3 groups for either serologic test. Magnitude of SN and ELISA titers varied greatly but independently of presence or absence of clinical signs of FHV-1-associated disease. Sensitivity, specificity, and positive and negative predictive values were assessed for VI and the IFA assay--jointly and individually--and for each SN and ELISA titer magnitude. Values never all exceeded 50%.

CLINICAL IMPLICATIONS

Because FHV-1 can be detected commonly in clinically normal cats by the IFA assay or VI, neither test appears to aid in the clinical diagnosis of FHV-1 infection. Seroprevalence does not appear to vary between affected and clinically normal cats. SN, ELISA, VI, and the IFA assay appear to be of limited value in the diagnosis of FHV-1-associated disease in cats. Concurrent assessment of the IFA assay and VI results may permit exclusion of FHV-1 as an etiologic agent if results of both tests are negative.

Regional seroprevalence of Cryptosporidium parvum-specific IgG of cats in the United States

The objective of this study was to determine the regional prevalence of Cryptosporidium parvum-specific IgG in the sera of cats in the United States. The continental United States was partitioned into eight regional areas. Serum samples from 75 cats from each region were assayed for C. parvum-specific IgG using an indirect enzyme-linked immunosorbent assay (ELISA). Age, sex, breed, and indoor/outdoor status were examined as possible risk factors for developing a positive C. parvum-specific IgG antibody titer. The presence of gastro-intestinal signs and Toxoplasma gondii-specific IgG in the serum were also evaluated for association with C. parvum seropositivity. Of the 600 samples assayed, 50 (8.3%) were positive for C. parvum-specific IgG. Regional seroprevalence ranged from 1.3% in the mid-Atlantic states to 14.7% in the south-eastern states. The oldest group of cats (>10 years) had the highest seroprevalence (15.3%). The prevalence of C. parvum-specific IgG was higher among male (10.1%) than among female cats (6.9%), although, the difference was not statistically significant (p = 0.17). Seropositivity was not associated with pure-bred status. C. parvum-specific IgG antibodies was detected most frequently in T. gondii-specific IgG seropositive cats, outdoor cats, and cats with gastro-intestinal signs. These results suggest that cats in the United States are commonly exposed to C. parvum.

Mammary gland uptake of sodium Tc-pertechnetate in a cat with a drug-induced gynecomastia

Sodium Tc-pertechnetate accumulated in the mammary glands of a male cat. It was determined that the uptake was attributable to gynecomastia induced by medroxyprogesterone acetate injections. Gynecomastia and pertechnetate uptake resolved following cessation of medroxyprogesterone acetate treatment.

Polymerase chain reaction for the detection of Toxoplasma gondii within aqueous humor of experimentally-inoculated cats

The purpose of this study was to determine the temporal appearance of T. gondii in aqueous humor of cats orally inoculated with T. gondii using polymerase chain reaction (PCR) for the detection of the B1 gene. Serum and aqueous humor were collected from five SPF cats prior to oral inoculation with T. gondii and days 7, 14, 21, 28, 42, 84, 140, 147, 154, 161, 168, and 182 after inoculation. Cats were inoculated orally with T. gondii tissue cysts on day 0 and day 140. T. gondii-specific IgM and IgG were measured in serum and aqueous humor from the cats at each sample data. T. gondii B1 gene PCR was performed on all the aqueous humor samples and the amplified DNA was detected by Southern blotting. Chorioretinitis developed in three out of the five cats, but anterior uveitis was not detected. All cats developed T. gondii-specific IgG titers in serum, and had T. gondii-specific IgG C-values > 1 in both eyes at varying times during the study. T. gondii was detected by PCR and Southern blotting in aqueous humor in both eyes of all cats at times varying from days 14-84 after primary inoculation and days 14-42 after challenge inoculation.