Feline bilateral inflammatory aural polyps: a descriptive retrospective study.

BACKGROUND: Feline inflammatory aural polyps (IP) have been reported as solitary growths, yet bilateral polyps may occur more commonly than described previously. OBJECTIVES: To identify the prevalence and risk factors associated with bilateral feline IP within a population of cats evaluated at a veterinary teaching hospital over a 10 year period. ANIMALS: Twenty-five cats with histologically confirmed IP. METHODS AND MATERIALS: A retrospective study was performed by searching computerized medical records of cats seen at The University of Tennessee Veterinary Teaching Hospital from 2005 to 2015. Keywords used for the search included "feline polyp", "ventral bulla osteotomy", "inflammatory polyp ear canal" and "nasopharyngeal polyp". RESULTS: Cats were separated into groups with unilateral or bilateral disease. Six of 25 (24%) cats had bilateral IP. Twelve cats had computed tomography performed (four of six with bilateral IP; eight of 19 with unilateral IP). Clinical signs, history of upper respiratory infection, post-treatment complications, and IP recurrence with and without local and systemic steroid administration were studied between groups and no differences were identified. In four of six cats with bilateral disease, the second polyp was identified with advanced imaging performed at the time of referral. CONCLUSIONS AND CLINICAL IMPORTANCE: These findings demonstrate that bilateral IP occur more frequently than reported previously and establish a prevalence for bilateral IP. These findings also highlight the value of advanced imaging techniques in diagnosing bilateral IP.

Antibacterial effect of N-acetylcysteine in combination with antimicrobials on common canine otitis externa bacterial isolates.

BACKGROUND: Approved treatments for canine otitis externa are limited in variety and may contain ototoxic ingredients. With bacterial resistance an ongoing concern, it would be ideal if non-ototoxic agents combined with antibiotics resulted in a synergistic effect, requiring lower antibiotic concentrations to treat infections. Evidence of synergism and antagonism between N-acetylcysteine (NAC) and various antibiotic classes has been reported; the present research group was interested in examining these interactions. HYPOTHESIS/OBJECTIVES: To determine if NAC, an otoprotective and antimicrobial compound, has synergistic activity when combined with enrofloxacin or gentamicin in vitro against bacterial isolates causing canine otitis externa. ANIMALS: Twenty-two isolates from canine clinical cases of otitis externa were identified and tested, including seven Staphylococcus pseudintermedius, 12 Pseudomonas aeruginosa and three Corynebacterium spp. isolates. METHODS AND MATERIALS: Each isolate was grown on blood agar for 24 h and transferred to Mueller-Hinton broth (MHB), with a final concentration of 5 × 105 cfu/mL. Each well was inoculated with 50 µL of bacterial suspension. N-acetylcysteine was diluted in MHB to a starting concentration of 160 mg/mL. Enrofloxacin and gentamicin were diluted to 64 µg/mL. Individual and checkerboard serial microdilution assays were performed in triplicate with negative controls for all isolates tested. RESULTS: Interactions observed for NAC and enrofloxacin were synergistic (4.5%), indifferent (77.3%) or antagonistic (18.2%). Interactions observed for NAC and gentamicin were synergistic (4.5%), indifferent (45.5%) or antagonistic (50%). CONCLUSIONS AND CLINICAL RELEVANCE: Most interactions between NAC and enrofloxacin or gentamicin were indifferent or antagonistic at the concentrations tested in vitro.

Description and characterization of a hair coat disorder in schipperkes.

BACKGROUND: Schipperkes develop bilaterally symmetrical alopecia preceded by lightening of the hair coat not associated with systemic clinical signs. The alopecia is presumptively diagnosed as Alopecia X but has never been investigated. HYPOTHESIS/OBJECTIVES: The purpose of this study was to describe clinical features, histopathological and laboratory abnormalities associated with symmetrical, noninflammatory alopecia in schipperkes. ANIMALS: Three healthy and eight affected schipperkes. METHODS AND MATERIALS: Complete blood count (CBC), serum chemistry panel, urinalysis (UA), urine cortisol: creatinine ratio (UCCR), total thyroxine (T4 ), free thyroxine by equilibrium dialysis (fT4 ed), thyroid stimulating hormone (TSH) and pre- and post-stimulation cortisol with sex hormone analyses were performed for all dogs. A minimum of two skin biopsy sites were sampled for histopathological evaluation. RESULTS: The CBC, serum chemistry panel, UA, T4 , fT4 ed, TSH and post-ACTH cortisol concentrations were normal for all dogs. Androstenedione concentrations were increased for all dogs; two of three healthy and five of eight affected dogs had increased post-ACTH androstenedione concentrations. Estradiol concentrations were increased for all healthy and four of eight affected dogs, with post-ACTH estradiol concentrations increased for all healthy and five of eight affected dogs. Progesterone concentrations were increased for two of three healthy and four of eight affected dogs. Post-ACTH progesterone concentrations were increased for one of three healthy and four of eight affected dogs. For one of three healthy and two of eight affected dogs, 17-hydroxyprogesterone concentrations were increased; post-ACTH 17-hydroxyprogesterone concentrations were increased in three of eight affected dogs only. Histopathology results from affected dogs were consistent with hair cycle arrest. CONCLUSIONS AND CLINICAL IMPORTANCE: This disorder resembles Alopecia X clinically and histologically.

The prevalence of Dermatophilus congolensis in horses with pastern dermatitis using PCR to diagnose infection in a population of horses in southern USA.

BACKGROUND: Dermatophilus congolensis is a facultative anaerobic actinomycete that causes papular to exudative dermatitis with crusting in horses. This organism is frequently implicated as a cause of pastern dermatitis, but few data are available validating the organism's association with this disease. HYPOTHESIS/OBJECTIVES: The aim of this study was to evaluate if D. congolensis is associated with pastern dermatitis in horses utilizing RT-qPCR. ANIMALS: Fifteen client-owned horses diagnosed with pastern dermatitis and eight client-owned unaffected control horses were utilized for this study. METHODS: A cross-sectional study was performed. History and physical examination findings were recorded, and samples were collected and tested for D. congolensis utilizing cytological evaluation and RT-qPCR. Dermatophyte culture and superficial skin scrapings were also performed. RESULTS: Ten of 15 horses with pastern dermatitis had feathered pasterns. Dermatophilus congolensis was identified by RT-qPCR from one nonfeathered horse but none with feathered pasterns. Cytological evaluation identified bacteria in all horses but failed to identify organisms resembling D. congolensis in any horse. Four of 15 horses, all feathered, were positive for Chorioptes mites. Fungal culture was negative for dermatophytes in all horses. All test results were negative for the eight control horses. CONCLUSIONS AND CLINICAL IMPORTANCE: Dermatophilus congolensis was uncommonly associated with pastern dermatitis in horses in this population. However, chorioptic mange was commonly associated with pastern dermatitis in feathered horses and represented an important differential diagnosis for this clinical presentation.

PCR analysis of a prescription vegetarian diet and use in three dogs with cutaneous adverse food reactions.

BACKGROUND: Cutaneous adverse food reaction (CAFR) is diagnosed by performing an elimination diet trial utilizing prescription or home-cooked diets followed by provocative challenge. OBJECTIVES: To report findings of PCR analysis of a prescription vegetarian diet (RCV) for undeclared proteins of animal origin, as well as to describe its utilization for diagnosis and management of dogs suspected of having CAFR. ANIMALS: Three client-owned dogs. METHODS: PCR analysis of RCV for 11 mammalian species and poultry. In three dogs, clinical examination, cytology, aerobic culture (if indicated) and at least one elimination diet trial with RCV. RESULTS: In our case series, all dogs had a history of pruritus and recurrent pyoderma that resolved with infection control and an elimination diet trial. In cases 1 and 2, a diagnosis of CAFR was made following an elimination trial with RCV and provocative challenge. Case 3 had a previously confirmed diagnosis of CAFR and RCV was successfully used to maintain remission of CAFR-related signs. PCR testing of RCV was negative for 11 mammalian species and poultry. CONCLUSIONS AND CLINICAL IMPORTANCE: The RCV diet was found not to contain any undeclared mammalian or avian proteins. In this case series, the RCV was successfully used to diagnose and maintain three dogs with CAFR.

Mycoplasma infection of the middle ear in three cats.

BACKGROUND: Mycoplasma spp. are commensal organisms found in association with the mucus membranes of all mammalian species and are implicated in bacterial infections of many different locations. Mycoplasma spp. as a primary pathogen associated with otitis media in cats has not been reported. OBJECTIVES: To describe three cats with Mycoplasma infection of the middle ear associated with various underlying disease processes. ANIMALS: Three client-owned cats. METHODS: Clinical examination, aerobic culture of the middle ear and computed tomography or magnetic resonance imaging of the skull. RESULTS: Mycoplasma spp. were grown on aerobic culture from the middle ear of three cats. In Case 1, concurrent neoplasia of the bulla was identified. Mycoplasma alone was cultured in Case 2 and Mycoplasma was grown in addition to Bordetella in Case 3. Case 1 was euthanized, Case 2 responded to Mycoplasma targeted therapy and Case 3 responded to Bordetella targeted therapy. CONCLUSIONS AND CLINICAL IMPORTANCE: Mycoplasma infections of the middle ear may be clinically important and require targeted treatment in some cases.

Use of mycophenolate mofetil to treat immune-mediated skin disease in 14 dogs - a retrospective evaluation.

BACKGROUND: Mycophenolate mofetil (MMF) is a lymphocytotoxic immunosuppressive agent used in human and companion animal medicine for the treatment of immune-mediated disease. Mycophenolate mofetil is reported to have reduced myelotoxicity and hepatotoxicity when compared to azathioprine. OBJECTIVES: It was hypothesized that treatment with MMF as a secondary agent with glucocorticoids would be effective in treating immune-mediated skin disease. In addition, adverse effects associated with the drug are reported. ANIMALS: Fourteen dogs from a hospital population diagnosed with immune-mediated skin disease. METHODS: A retrospective review of medical records from 2010 to 2015 was used to identify dogs with immune-mediated skin disease that were treated with MMF. RESULTS: All dogs were treated with MMF (mean dose 14.7 mg/kg twice daily) in conjunction with glucocorticoids. Ten of 14 cases showed positive results, with complete remission in eight cases and partial remission in two cases. Mean time to remission was 5.7 weeks. Therapy was discontinued in one case (perianal fistula) due to lack of response. Adverse events were noted in six cases and included diarrhoea (n = 6), haematochezia (n = 2), vomiting (n = 3) and papilloma formation (n = 1). Therapy was discontinued in two cases with diarrhoea. Mycophenolate mofetil was discontinued in an additional case because of a diagnosis of neoplasia. All other adverse events were self-limiting or easily medically managed. No hepatotoxicity or bone marrow suppression was noted. CONCLUSION: This study supports the use of MMF as a second-line immunotherapeutic in immune-mediated skin disease in dogs.

Antibacterial effect of N-acetylcysteine on common canine otitis externa isolates.

BACKGROUND: N-Acetylcysteine (NAC) has the potential to be a useful therapeutic agent for the treatment of otitis externa due to its antimicrobial and mucolytic properties, as well as its ability to disrupt bacterial biofilm. HYPOTHESIS/OBJECTIVES: To determine the antibacterial activity of NAC against common bacterial isolates associated with canine otitis externa. ANIMALS: Twenty two isolates from canine clinical cases of otitis externa were identified and tested, including five Staphylococcus pseudintermedius, six Pseudomonas aeruginosa, five Corynebacterium spp. and six ß-haemolytic Streptococcus spp. isolates. METHODS: Each isolate was grown on blood agar for 24 h and transferred to Mueller Hinton Broth (MHB) to achieve a final concentration of 5 × 10(5)  CFU/mL. NAC was diluted in MHB to a starting concentration of 160 mg/mL and serial two-fold microdilution assays were performed in triplicate with negative controls for all isolates tested. Concentrations of NAC tested ranged from 0.125 to 80 mg/mL. A 50 µL volume of bacterial suspension was used to inoculate each well. RESULTS: The minimum inhibitory concentration (MIC) of NAC for all isolates tested ranged from 5 to 20 mg/mL. CONCLUSIONS AND CLINICAL RELEVANCE: N-Acetylcysteine inhibits clinically relevant and drug resistant bacteria in vitro, and has potential for use as a novel agent for treatment of otitis externa.

Erythema multiforme associated with zonisamide in a dog.

This report describes a dog that developed erythema multiforme in temporal association with administration of the sulphonamide-based anticonvulsant drug zonisamide. Similar adverse drug reactions have been associated with sulphonamide antimicrobial drugs. Caution should be exercised when prescribing this medication for dogs with known hypersensitivity to sulphonamides.

Nasal carriage of Staphylococcus schleiferi from healthy dogs and dogs with otitis, pyoderma or both.

In veterinary medicine, Staphylococcus schleiferi was previously assumed to be an inhabitant of carnivore skin, however, more recently, it has been repeatedly documented in the literature as both an inhabitant and as a pathogen. In order to determine the frequency of nasal carriage, and the methicillin susceptibility pattern of S. schleiferi from healthy dogs as well as dogs with otitis and/or pyoderma, a prospective study including 24 dogs with healthy ears and skin, 27 dogs with healthy ears and pyoderma, 15 dogs with otitis without pyoderma and 20 dogs with both otitis and pyoderma was performed. Specimens were obtained and cultured and isolates were identified as S. schleiferi based on growth and biochemical characteristics. S. schleiferi was isolated from the nares of 1 healthy dog, 3 dogs with recurrent pyoderma, 2 dogs with recurrent otitis, and 1 dog with both recurrent otitis and pyoderma. One of the S. schleiferi isolates was methicillin resistant. Nasal carriage of S. schleiferi does occur in healthy dogs as well as dogs with otitis and pyoderma. Methicillin resistant and sensitive S. schleiferi can be found in the nares of dogs with diseased ears and skin.

Terbinafine pharmacokinetics after single dose oral administration in the dog.

Terbinafine is an allylamine antifungal prescribed for the treatment of mycoses in humans. It is increasingly being used in veterinary patients. The purpose of this study was to evaluate the pharmacokinetic properties of terbinafine in dogs after a single oral dose. Ten healthy adult dogs were included in the study. A single dose of terbinafine (30-35 mg/kg) was administered orally, and blood samples were periodically collected over a 24 h period during which dogs were monitored for adverse effects. Two of 10 dogs developed transient ocular changes. A high-performance liquid chromatography assay was developed and used to determine plasma terbinafine concentrations. Pharmacokinetic analysis was performed using PK Solutions(®) computer software. Area under the curve (AUC) from time 0 to 24 h was 15.4 µg·h/mL (range 5-27), maximal plasma concentration (C(max) ) was 3.5 µg/mL (range 3-4.9 µg/mL) and time to C(max) (T(max) ) was 3.6 h (range 2-6 h). The time above minimal inhibitory concentration (T > MIC) as well as AUC/MIC was calculated for important invasive fungal pathogens and dermatophytes. The T > MIC was 17-18 h for Blastomyces dermatitidis, Histoplasma capsulatum and dermatophytes (Microsporum spp. and Trichophyton mentagrophytes), while the MIC for Sporothrix schenckii and Coccidioides immitis was exceeded for 9.5-11 h. The AUC/MIC values ranged from 9 to 13 µg h/mL for these fungi. Our results provide evidence supporting the use of terbinafine as an oral therapeutic agent for treating systemic and subcutaneous mycoses in dogs.

Extracutaneous neutrophilic inflammation in a dog with lesions resembling Sweet's Syndrome.

A 7-year-old-spayed female standard poodle dog presented to the Iowa State University Veterinary Teaching Hospital with an 8-day history of lethargy, left hind limb lameness, ptyalism and peripheral lymphadenomegaly. On physical examination, the dog was lethargic, febrile (40.5 degrees C) and had multifocal to coalescing erythematous papular to pustular eruptions on the skin of all four limbs, periocularly and on the ventral and lateral thorax and abdomen. Histopathological findings from skin biopsies of the papules revealed a severe diffuse neutrophilic dermatitis with sub- and intra-epithelial pustules. Four days after being admitted the dog died from cardiac and respiratory failure. At necropsy, in addition to the multifocal to coalescing erythematous papules, the skin contained scattered pustules. Additionally, the subcutaneous tissue surrounding the right stifle was diffusely oedematous, and the peripheral and visceral lymph nodes were enlarged. The predominant histologic lesion was neutrophilic inflammation, in the absence of detectable bacteria in the skin, heart, lungs, oesophagus and left tarsus. In the absence of neoplasia or bacteraemia, a syndrome similar to Sweet's Syndrome should be considered as a differential diagnosis in dogs with cutaneous and extracutaneous neutrophilic infiltrates.

Isolation of Staphylococcus schleiferi from healthy dogs and dogs with otitis, pyoderma, or both.

OBJECTIVE: To determine the frequency of isolation and susceptibility patterns of Staphylococcus schleiferi from healthy dogs and dogs with otitis, pyoderma, or both that had or had not received antimicrobial treatment. DESIGN: Prospective study. ANIMALS: 50 dogs. PROCEDURE: Dogs were allocated to 1 of 4 groups: healthy dogs (n=13), dogs without otitis but with pyoderma (10), dogs with otitis but without pyoderma (11), and dogs with otitis and pyoderma (16). Bacteriologic culture of ear swab specimens was performed in all dogs. Bacteriologic culture of skin swab specimens was also performed in dogs with concurrent pyoderma. Isolates were identified as S schleiferi subsp schleiferi or S schleiferi subsp coagulans on the basis of growth and biochemical characteristics. RESULTS: S schleiferi was not isolated from any dogs with pyoderma only. Staphylococcus schleiferi subsp schleiferi was isolated from the ears of 2 healthy dogs, and the skin and ears of 2 dogs and the skin of 1 dog with otitis and pyoderma. Staphylococcus schleiferi subsp coagulans was isolated from the ears of 3 dogs with otitis only, and the ears of 6 dogs and the skin of 2 dogs with otitis and pyoderma. One of the S schleiferi subsp schleiferi isolates from ears, 2 of the S schleiferi subsp coagulans isolates from ears, and 1 of the S schleiferi subsp coagulans isolates from the skin were resistant to methicillin. One methicillin-resistant isolate from the ears and 1 from the skin were also resistant to fluoroquinolones. CONCLUSIONS AND CLINICAL RELEVANCE: S schleiferi subsp schleiferi was detected in healthy dogs and dogs with otitis and pyoderma. Methicillin-resistant and -susceptible S schleiferi subsp schleiferi and S schleiferi subsp coagulans were detected as the predominant organisms in dogs with otitis.

Effects of sulfamethoxazole-trimethoprim on thyroid function in dogs.

OBJECTIVE: To evaluate effects of trimethoprim-sulfamethoxazole (T/SMX) on thyroid function in dogs. ANIMALS: 6 healthy euthyroid dogs. PROCEDURE: Dogs were administered T/SMX (14.1 to 16 mg/kg, PO, q 12 h) for 3 weeks. Blood was collected weekly for 6 weeks for determination of total thyroxine (TT4), free thyroxine (fT4), and canine thyroid-stimulating hormone (cTSH) concentrations. Schirmer tear tests were performed weekly. Blood was collected for CBC prior to antimicrobial treatment and at 3 and 6 weeks. RESULTS: 5 dogs had serum TT4 concentrations equal to or less than the lower reference limit, and 4 dogs had serum fT4 less than the lower reference limit after 3 weeks of T/SMX administration; cTSH concentrations were greater than the upper reference limit in 4 dogs. All dogs had TT4 and fT4 concentrations greater than the lower reference limit after T/SMX administration was discontinued for 1 week, and cTSH concentrations were less than reference range after T/SMX administration was discontinued for 2 weeks. Two dogs developed decreased tear production, which returned to normal after discontinuing administration. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that administration of T/SMX at a dosage of 14.1 to 16 mg/kg, PO, every 12 hours for 3 weeks caused decreased TT4 and fT4 concentrations and increased cTSH concentration, conditions that would be compatible with a diagnosis of hypothyroidism. Therefore, dogs should not have thyroid function evaluated while receiving this dosage of T/SMX for >2 weeks. These results are in contrast to those of a previous study of trimethoprim-sulfadiazine.

Effects of a mock ultrasonographic procedure on cortisol concentrations during low-dose dexamethasone suppression testing in clinically normal adult dogs.

OBJECTIVE: To determine whether the stress of an ultrasonographic procedure would interfere with the suppressive effect of dexamethasone during a low-dose dexamethasone suppression test (LDDST) in healthy dogs. ANIMALS: 6 clinically normal adult dogs. PROCEDURE: In phase 1, an LDDST was performed 5 times at weekly intervals in each dog. Serum samples were obtained 0, 2, 4, 6, and 8 hours after dexamethasone injection. A mock 20-minute abdominal ultrasonographic examination was performed on all dogs at each time point during the LDDST on weeks 2 through 5. In phase 2, serum cortisol concentrations were measured before and immediately after a 20-minute mock abdominal ultrasonographic examination, as described for phase 1. RESULTS: We did not detect significant differences after dexamethasone injection when comparing median cortisol concentrations for weeks 2 to 5 (mock ultrasonographic procedure) with median concentration for week 1 (no mock ultrasonographic procedure). For 5 of the 6 dogs, cortisol concentrations after dexamethasone injection decreased to < 35.9 nmol/L after each mock ultrasonographic procedure and remained low for the duration of the LDDST. In phase 2, all dogs had significant increases in cortisol concentrations immediately after the mock ultrasonographic procedure. CONCLUSIONS AND CLINICAL RELEVANCE: A 20-minute mock abdominal ultrasonographic examination performed during LDDST did not alter results of the LDDST in most dogs. Cortisol concentrations measured immediately after a mock ultrasonographic examination were significantly increased. Ultrasonographic procedures should be performed a minimum of 2 hours before collection of samples that will be used to measure cortisol concentrations.