Feline pyoderma therapy

Feline pyoderma is a disease entity more prevalent than previously described. Diagnosis is made by finding bacteria in the presence of inflammatory cells or bacterial phagocytosis on routine cytological examination. Diseases leading to secondary bacterial pyoderma include allergic and inflammatory skin diseases, parasitosis, feline chin acne, and others. Lesions of feline pyoderma are variable and include crusted and eroded papules, pustules, furuncles, eroded to ulcerated plaques with variable exudation and crusting, and linear to nodular ulcerative granulomatous lesions. Three cases of feline pyoderma responsive to antimicrobial therapy are discussed: case 1, a 10.5-year-old male neutered domestic short hair with eosinophilic lip ulcer, case 2, a 7-year-old male neutered domestic short hair with multiple cutaneous eosinophilic plaques, and case 3, an 8-month-old male neutered domestic short hair cat with Pseudomonas dermatitis, vasculitis, and panniculitis. Antibiotic selection for treatment of feline pyoderma should be based on cytological examination, and culture and sensitivity in unresponsive cases.     

Responsiveness and validity of the SCORFAD, an extent and severity scale for feline hypersensitivity dermatitis

Background – Hypersensitivity (allergic) dermatitis (HD) is commonly seen in cats, causing pruritus and various patterns of skin lesions, including at least one of the following: head and neck excoriations, self‐induced alopecia, eosinophilic plaques and miliary dermatitis. Few studies have evaluated the efficacy of therapeutic interventions for feline HD, and although various scales have been considered, none has been formally validated for the assessment of disease severity and its response to therapy. Objective – To design and validate a novel scale (SCORing Feline Allergic Dermatitis; SCORFAD) to assess the value of different criteria used as outcome measures for the treatment of feline HD and to set minimal thresholds for defining the clinical success of tested interventions. Animals – One hundred client‐owned cats. Methods – The SCORFAD scale was designed to include the four most frequently identified lesion types in feline HD (eosinophilic plaque, head and neck excoriations, self‐induced alopecia and miliary dermatitis) across 10 body regions. The extent and severity of each lesion type were graded prior to inclusion and after 3 and 6 weeks in a clinical study to compare the efficacy of two doses of ciclosporin with placebo. Results – The SCORFAD scale was found to exhibit satisfactory content, construct, criterion and sensitivity to change. The percentage reduction in SCORFAD from baseline was determined to be the most valid assessment of clinical response. Inter‐ and intra‐observer reliability was not assessed. Conclusions and clinical importance – The SCORFAD scale is proposed for use as a validated tool for the assessment of disease severity and response to therapeutic interventions in clinical trials for feline HD.     

Evaluation of the bacterial microflora of the conjunctival sac of healthy dogs and dogs with atopic dermatitis

The aim of this case–control study was to evaluate and compare the bacterial microflora from the conjunctival sac of dogs with atopic dermatitis and healthy dogs. Twenty‐one atopic dogs without clinical and/or cytopathological signs of bacterial blepharoconjunctivitis and 21 breed‐matched healthy dogs were enrolled. Under topical anaesthesia, the inferior conjunctival sac of one eye was scraped twice. Material was collected with a Kimura spatula, spread over a slide and stained with a Diff Quick^®‐type stain (Medion Diagnostics GmbH, Düdingen, Switzerland) for cytological examination. An area of 0.5 cm² was examined at ×1000 magnification, and the types and numbers of cells and bacteria were recorded. A bacterial swab was collected and inoculated into culture media for the growth of aerobic bacteria. Before sampling, each atopic dog was evaluated for severity of cutaneous lesions, pruritus and conjunctival inflammation. Significant differences were observed between atopic and healthy dogs for the presence of bacteria on cytology (P = 0.015), keratinized (P = 0.001) and nonkeratinized epithelial cells (P = 0.013), eosinophils (P = 0.019) and lymphocytes (P = 0.008). Bacteria were recovered from 12 atopic dogs and three healthy dogs (P = 0.004). Staphylococcus pseudintermedius was the most commonly isolated species in atopic dogs (seven of 12). In atopic dogs, no significant relation was found between conjunctival bacterial colonization (on cytology and culture) and the severity of any of the clinical parameters. This study suggests differences in conjunctival bacterial colonization and cytological features between atopic and healthy dogs.     

Exposure Time‐Dependent Bactericidal Activities of Amoxicillin Against Actinobacillus pleuropneumoniae; an In Vitro and In Vivo Pharmacodynamic Model

The pharmacodynamic effects of amoxicillin against Actinobacillus pleuropneumoniae at exposure concentration above and below minimum inhibitory concentration (MIC) were evaluated in both in vitro and in vivo. In vitro, the growth and morphological change of A. pleuropneumoniae in culture medium was observed. In vivo, the efficacy of amoxicillin on experimentally induced A. pleuropneumoniae infection in disease‐free pigs was evaluated. Fifteen pigs were divided into three groups (n = 5 per group). After the onset of clinical respiratory disease symptoms, 6 h post‐infection, amoxicillin sustained‐release injectable formulation was injected intramuscularly at 7.5 mg/kg/day (group I) and 15 mg/kg/day (group II). Then the serum concentration of amoxicillin was measured. An untreated infected group served as controls. In each amoxicillin administration group, if symptoms were not absent after 48 h, the pig was injected with the amoxicillin sustained‐release injectable formulation again using the same dosage. In vitro, the growth of A. pleuropneumoniae inhibited by amoxicillin exposure at the concentration above the MIC (1.28 × MIC), and the inhibition time was in directly proportion to the time of amoxicillin exposure. Moreover, all the cells were lysed. Whereas the bacterial growth inhibition at the amoxicillin exposure concentration below the MIC (0.25 × MIC) was not done, and the shape of cells were normal or long filamentous. In vivo, the group I clinical and pathological score was higher than the group II, and the group I weight gain was significantly less than the group II. Performance with respect to weight gain corresponded with clinical signs. The infected control group was severely affected with an 80% (4/5) mortality rate 24–96 h post‐challenge. The duration of time above MIC (T > MIC) of serum amoxicillin concentration in the group I was less than group II. The present studies suggest that amoxicillin has exposure time‐dependent bactericidal activity against A. pleuropneumoniae.     

A randomized double-blinded placebo-controlled study to evaluate an effective ciclosporin dose for the treatment of feline hypersensitivity dermatitis

Background – Hypersensitivity dermatitides (HD) are frequently suspected in cats, but there are few clinical studies on safe and effective treatments in the published literature. Objectives – To establish a safe and effective dose of ciclosporin in the treatment of feline HD. Animals – One hundred client‐owned cats with feline HD. Methods – Double‐blind study, with cats randomly assigned to receive ciclosporin at either 7.0 mg/kg once daily (n = 33) or 2.5 mg/kg once daily (n = 32) or a placebo (n = 35) for 6 weeks. Results – Mean Total Lesion Scores with 7.0 mg/kg ciclosporin were significantly lower than with 2.5 mg/kg ciclosporin (P = 0.0047) or placebo (P = 0.0003) at study end. Individual Total Lesion Scores improved by >50% in 70% of the 7.0 mg/kg group, compared with 47% in the 2.5 mg/kg group and 23% in the placebo group (P = 0.0006). The investigators’ Global Assessment of Improvement was ‘excellent’ or ‘good’ in 61% of cats treated with 7.0 mg/kg ciclosporin, compared with 47% of cats given 2.5 mg/kg and 23% given placebo. The improvement in Investigator Pruritus Scores was significantly greater in cats treated with 7.0 mg/kg ciclosporin (54%) compared with both 2.5 mg/kg ciclosporin (32%; P = 0.0232) and placebo (21%; P = 0.0063). Mild gastrointestinal disorders were the most common adverse events, but these did not require cessation of therapy. Conclusions and clinical importance – Results suggest that 7.0 mg/kg ciclosporin once daily in food or per os for 6 weeks is effective and well tolerated in feline HD.     

Effects of zinc-L-carnosine and vitamin E on aspirin-induced gastroduodenal injury in dogs

Background: Nonsteroidal anti‐inflammatory drugs frequently cause gastrointestinal (GI) injury. Zinc‐l ‐carnosine has antioxidant, anti‐inflammatory, mucosal protective, and healing properties in rodent models and in some human studies of GI injury. Hypothesis: The combination of zinc‐l ‐carnosine and vitamin E attenuates aspirin‐induced gastroduodenal mucosal injury. Animals: Eighteen healthy random‐source Foxhound dogs. Methods: In this randomized, double‐blinded, placebo‐controlled study dogs were treated with placebo (n = 6; 0X group), 30 mg/30 IU (n = 6; 1X group), or 60 mg/60 IU (n = 6; 2X group) zinc‐l ‐carnosine/vitamin E orally every 12 hours for 35 days. Between Day 7 and 35, GI mucosal lesions were induced with aspirin (25 mg/kg PO q8h). Mucosal injury lesions (hemorrhage, erosion, and ulcer) were assessed by gastroduodenoscopy on Days 14, 21, and 35 with a 12‐point scoring scale. Results: At baseline (Day ?1) gastroscopy scores were not significantly different between groups (mean ± SD: 0X, 4.4 ± 0.8; group 1X, 4.4 ± 0.6; group 2X, 4.2 ± 0.3; P= .55). Gastroscopy scores increased significantly in all groups between Day ?1 and Days 14, 21, and 35 (P < .0001). On Day 35, gastroscopy scores were 29.2 ± 5.2 (0X), 27.3 ± 3.7 (1X), and 28.6 ± 3.3 (2X). Mean gastroscopy scores were not significantly different among treatment groups on any of the days (P= .61). Conclusions and Clinical Importance: Administration of the combination of zinc‐l ‐carnosine and vitamin E at 1X or 2X dosing did not attenuate aspirin‐induced gastroduodenal mucosal injury.     

Airway microbial culture and susceptibility patterns in dogs and cats with respiratory disease of varying severity

Objective – To compare airway microbiological culture and susceptibility results in 2 groups of dogs and cats: 1 with respiratory failure requiring positive pressure ventilation (PPV) and 1 with respiratory disease. Design – Retrospective study. Setting – University teaching hospital. Animals – Fifty‐two dogs and cats requiring PPV that had an airway microbiologic culture submitted from October 1, 2003 to October 31, 2008 were included. One hundred and four airway microbiologic cultures from dogs and cats with respiratory disease not requiring PPV were randomly sampled for comparison. Interventions – None. Measurements and Main Results – Patients with respiratory failure were more likely to have a gram‐negative enteric isolate identified (P<0.001), while patients with respiratory disease were more likely to have a gram‐negative nonenteric isolate (P<0.001) or anaerobic isolate (P<0.001) identified. Aerobic bacterial isolates from patients with respiratory failure were less likely to be susceptible to ampicillin (P=0.006), amoxicillin/clavulonate (P<0.001), chloramphenicol (P=0.004), enrofloxacin (P<0.001), ticarcillin/clavulonate (P=0.004), and the combination of ampicillin with enrofloxacin (P<0.001) than were aerobic bacterial isolates from patients with respiratory disease. Conclusions – Canine and feline patients with respiratory failure severe enough to require PPV exhibit a different pattern of bacterial isolates cultured from their airways when compared with isolates from patients with respiratory disease that has not resulted in ventilator dependence. These isolates are more likely to be resistant to commonly used antimicrobials/antimicrobial combinations than patients in the respiratory disease group. These findings suggest that in canine and feline patients with infectious lower respiratory tract disease, consideration of the severity of the pulmonary insult may allow for better prediction of likely isolates and their antimicrobial susceptibilities. Further prospective studies with a standardized collection technique are warranted.     

Feline eosinophilic conjunctivitis

Objective To review 12 cases of histologically confirmed feline eosinophilic conjunctivitis, their clinical, cytologic, histologic and electronmicroscopic findings, results on PCR for FeHV‐1, treatment and outcome. Animals studied Twelve naturally occurring cases presented during a period of 26 months. Procedures Thorough ophthalmologic examination, conjunctival scrapings performed with the cytobrush method; histologic samples from the palpebral conjunctiva; PCR for FeHV‐1 on Schirmer Tear Test (STT) strips; saliva and nasal swabs, and retrospective evaluation of all results. Results The breed most commonly affected was the Domestic Shorthair (n = 8), followed by Persians (n = 2), Somali (n = 1) and Siamese (n = 1). Age at presentation was 1–15 years with a mean age of 7.2 years. Nine cats were castrated males; three cats were females: two of them were spayed. Unilateral (n = 7) or bilateral (n = 5) involvement with depigmentation and erosions of lid margin, blepharospasm, swelling and redness of conjunctiva and third eyelid were the most common clinical findings. Frequency of eosinophils in cytologic samples was more than 10% in every patient. PCR for FeHV‐1 on STT was negative in all cases. Histologically, eosinophils, lymphocytes, plasma cells, mast cells and macrophages were involved. On electronmicroscopy, viral particles were not detected. Ten cases needed long‐term anti‐inflammatory treatment. Conclusions The 12 reviewed cases suggest that feline eosinophilic conjunctivitis is a chronic inflammatory uni‐ or bilateral disease of the adult cat. Typically the lid margin was also involved, and was thickened, depigmented and erosive. Cytological examination of conjunctival scrapings was a valuable tool for detecting eosinophilic conjunctivitis. The cytological findings correlated well with the histopathological findings in our patients. Topical or systemic anti‐inflammatory drugs resolved the clinical symptoms in our cases within a short period of time. Neither electronmicroscopy nor PCR were able to detect involvement of FHV1 in the represented cases. The etiopathogenic role of FeHV‐1 remains undetermined.     

P‐48 Treatment of localized lesions of canine atopic dermatitis with tacrolimus ointment: a blinded,randomized, controlled trial

The purpose of this study was to determine whether tacrolimus ointment (Protopic) decreased the severity of localized lesions of canine atopic dermatitis (AD). Twenty dogs with AD were enrolled if they exhibited skin lesions localized to both front metacarpi. Each foot was randomized to be treated either with 0.1% tacrolimus or placebo (vaseline) ointment twice daily for 6 weeks. The nature of treatment for each foot lesion was concealed from the clinician. Before, and every 2 weeks during the study, erythema, lichenification, oozing and excoriations each were graded on a 10‐point scale (maximal total score: 40). The primary outcome measures consisted of the percentage reduction from baseline of lesional scores, and the number of subjects whose scores had decreased by 50% or greater by the end of the study. Intent‐to‐treat analyses were used. At the beginning of the study, lesional scores were not significantly different between treatment groups. After 6 weeks, the percentage reduction from baseline scores was higher for tacrolimus‐treated sites [median: 63% (95% CI: 39–67)] than for placebo‐treated feet [3% (‐2‐13)] (paired t‐test; P < 0.0001). When tacrolimus was applied, lesions decreased by 50% or greater in 15 dogs (75%), while this benchmark was not reached for any placebo‐treated feet (Fisher's exact test; P < 0.0001). Adverse drug events consisted of minor irritation in some dogs treated with tacrolimus. Results of this randomized, controlled trial suggest that the daily application of 0.1% tacrolimus ointment is useful for reducing the severity of localized skin lesions of canine AD. Funding: Self‐funded.     

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 Endobronchial Challenge with Actinobacillus pleuropneumoniae Serotype 10 of Pigs Vaccinated with Bacterins Consisting of A. pleuropneumoniae Serotype 10 Grown under NAD‐Rich and NAD‐Restricted Conditions

The efficacy of two bacterins containing an Actinobacillus pleuropneumoniae serotype 10 strain was evaluated. The bacterial cells constituting bacterin 1 and 2 were grown under nicotinamide adenine dinucleotide (NAD)‐rich (low‐adherence capacity to alveolar epithelial cell cultures) and NAD‐restricted (high‐adherence capacity to alveolar epithelial cell cultures) conditions, respectively. Ten pigs were vaccinated twice with the bacterin 1 and nine pigs with the bacterin 2. Ten control animals were injected twice with a saline solution. Three weeks after the second vaccination, all pigs were endobronchially inoculated with 106.5 colony‐forming units (CFU) of an A. pleuropneumoniae serotype 10 strain. In the bacterin 1 and 2 group, three and two pigs died after inoculation, respectively. Only two pigs of the control group survived challenge. Surviving pigs were killed at 7 days after challenge. The percentage of pigs with severe lung lesions (>10% of the lung affected) was 100% in the control group, 70% in the bacterin 1 group and 22% in the bacterin 2 group. Actinobacillus pleuropneumoniae was isolated from the lungs of all animals. The mean bacterial titres of the caudal lung lobes were 7.0 × 10⁶ CFU/g in the control group, 6.3 × 10⁵ CFU/g in the bacterin 1 group and 1.3 × 10⁶ CFU/g in the bacterin 2 group. It was concluded that both bacterins induced partial protection against severe challenge. Furthermore, there are indications that the bacterin 2, containing A. pleuropneumoniae bacteria grown under conditions resulting in high in vitro adhesin, induced better protection than the bacterin 1.     

Effect of oral supplementation of probiotic strains of Lactobacillus rhamnosus and Enterococcus faecium on the composition of the faecal microbiota of foals

Effects of probiotics on the intestinal microbiota of foals are yet insufficiently studied. The aim of this study was to investigate whether supplementation of Lactobacillus rhamnosus (DSM 7133) and Enterococcus faecium (DSM 7134) influences the bacterial composition of the faecal microbiota of foals. A total of 34 newborn foals were randomly assigned to the placebo group (PG, n = 16) and the treatment group (TG, n = 18). From day 1 to day 14 of life, foals orally received 3 ml of either a probiotic preparation (1.05 × 10⁹ CFU E. faecium and 4.50 × 10⁸ CFU L. rhamnosus) or placebo (carrier) once a day. Faeces were collected directly from the rectum immediately after birth (meconium) and at day 14 and day 56 of life. Samples of 12 foals per group were selected for microbiological analysis. DNA was extracted and used for polymerase chain reaction–denaturing gradient gel electrophoresis (PCR‐DGGE) and quantitative PCR. No DNA or amplicons were obtained from meconium. There were no differences in richness of bands and Shannon index of diversity regarding the Clostridium cluster XIVa between groups. Cluster analysis and principal coordinate analysis of DGGE data showed a clear effect of age. Band‐based similarity of bacterial clusters (Dice coefficient) decreased from day 14 to day 56 of life (p < 0.001) in PG foals only resulting in lower similarity in PG versus TG foals when 2 month old (p < 0.01). Five of thirty re‐amplified bands were identified on species level. Others were assigned either to family (mainly Lachnospiraceae) or genus level (Akkermansia). The bands related to Akkermansia muciniphila or Akkermansia spp. appeared almost in all DGGE profiles. Two‐week supplementation of the probiotic preparation to foals had no significant impact on the composition of the faecal microbiota but it appears to have prevented the reduction of bacterial similarity between 2 and 8 weeks of age observed in not treated foals.     

Investigation of the clinical efficacy of 0.2% topical stannous fluoride for the treatment of canine superficial pyoderma: a prospective,randomized, double‐blinded,placebo‐controlled trial

Stannous fluoride (SF) is an antibacterial compound that has been successfully used to treat gingivitis in people and dogs, and cutaneous bacterial infections in horses. The purpose of this prospective, double‐blinded, placebo‐controlled clinical trial was to investigate the efficacy of 0.2% SF spray (BacDerm^®; Emerald 3 Enterprises Inc., Camdenton, MO, USA) for the treatment of canine superficial pyoderma. Twenty‐six privately owned dogs with bacterial skin infections diagnosed on clinical signs, cytology and aerobic culture were enrolled. Dogs were randomly assigned to vehicle only or active ingredient treatment groups. The product was applied topically to affected areas once daily for 28 days, with assessments at days 0, 14, 28 and 42. Clinical and cytological evaluations were performed by the same investigators at each visit. Owners scored the improvement of hair coat, odour, pruritus and overall improvement at each recheck. Linear mixed models showed significant effects of treatment (P < 0.0001) and time (P = 0.0037) for investigator’s scores, and a significant time effect for owners’ haircoat (P = 0.0077) and odour (P = 0.0170) improvement scores. Dogs in both placebo and SF groups showed some improvement over time, and the investigator’s scores on days 0 and 28 were not significantly different between groups for both (t‐test P > 0.05). Spearman’s rho correlation coefficients revealed a significant negative correlation between investigator’s scores and all categories of owners’ assessment scores in dogs of both groups. Although some dogs improved on SF, this study does not support the use of 0.2% SF as sole therapy for canine superficial pyoderma.     

COMPARISON BETWEEN 2‐18F‐FLUORO‐2‐DEOXY‐D‐GLUCOSE POSITRON EMISSION TOMOGRAPHY AND CONTRAST‐ENHANCED COMPUTED TOMOGRAPHY FOR MEASURING GROSS TUMOR VOLUME IN CATS WITH ORAL SQUAMOUS CELL CARCINOMA

Feline oral squamous cell carcinoma is one of the most refractory feline malignancies. Most patients succumb due to failure in local tumor control. 2‐¹⁸F‐fluoro‐2‐deoxy‐D‐glucose positron emission tomography (¹⁸F‐FDG PET) is increasingly being used for veterinary oncology staging as it highlights areas with higher glucose metabolism. The goal of the current prospective study was to compare gross tumor volume measurements using ¹⁸F‐FDG PET vs. those using computed tomography (CT) for stereotactic radiation therapy planning in cats with oral squamous cell carcinoma. Twelve cats with confirmed oral squamous cell carcinoma underwent pretreatment ¹⁸F‐FDG PET/CT. Gross tumor volumes based on contrast‐enhanced CT and ¹⁸F‐FDG PET were measured and compared among cats. Mean PET gross tumor volume was significantly smaller than mean CT gross tumor volume in the mandibular/maxillary squamous cell carcinoma group (n = 8, P = 0.002) and for the total number of patients (n = 12, P = 0.006), but not in the lingual/laryngeal group (n = 4, P = 0.57). Mismatch fraction analysis revealed that most of the lingual/laryngeal patients had a large region of high‐¹⁸F‐FDG activity outside of the CT gross tumor volume. This mismatch fraction was significantly greater in the lingual/laryngeal group than the mandibular/maxillary group (P = 0.028). The effect of poor spatial resolution of PET imaging was greater when the absolute tumor volume was small. Findings from this study indicated that ¹⁸F‐FDG PET warrants further investigation as a supplemental imaging modality in cats with oral squamous cell carcinoma because it detected regions of possible primary tumor that were not detected on CT images.     

Feline bacterial urinary tract infections: An update on an evolving clinical problem

Although feline urine is increasingly submitted for bacterial culture and susceptibility testing as part of a more general diagnostic work-up for a range of presentations in veterinary practice, bacterial urinary tract infections (UTIs) are relatively uncommon due to a variety of physical and immunological barriers to infection. Culture positive urine is most often obtained from older female cats and the clinical history may include hematuria, dysuria and pollakiuria, or the infection may be occult. Urinalysis usually reveals hematuria and pyuria, and Escherichia coli and Gram-positive cocci are cultured most frequently. Most feline UTIs can be successfully treated using oral amoxicillin or amoxicillin/clavulanic acid administered for at least 14 days, but the prevalence of antimicrobial resistance amongst infecting bacterial species is a growing concern. There is currently no conclusive information on the safety and efficacy of alternative therapeutic agents for the treatment of feline UTIs.     

FC‐39 Successful management of canine atopic dermatitis using a plant extract: a randomized,double‐blinded,placebo‐controlled trial

This study evaluated the efficacy of Phytopica^TM, a proprietary blend of standardised plant extracts, in canine atopic dermatitis (AD). One hundred twenty dogs with perennial AD were recruited on the basis of history and clinical signs, and a positive intradermal allergen test or rFcεRIα serology to perennial allergens. Other pruritic dermatoses were eliminated by antimicrobial treatment, skin scrapings, Sarcoptes serology, flea control and a 6‐week food trial. Exclusion criteria included antimicrobial therapy within 7 days, antihistamines within 14 days, oral/topical glucocorticoids or cyclosporin within 28 days, and parenteral glucocorticoids, essential fatty acids or immunotherapy within 56 days of entry into the study. Dogs [minimum Canine Atopic Dermatitis Extent and Severity Index (CADESI) = 25] were randomly allocated to receive placebo, 100, 200 or 400 mg/kg Phytopica^TM daily for 12 weeks. Their CADESI was assessed every 4 weeks. A modified intention‐to‐treat population was analysed. The mean reductions in CADESI scores at the end of treatment compared to baseline were 4.4% (100 mg/kg; n = 30), 23.4% (200 mg/kg; n = 29, P < 0.01), 8.5% (400 mg/kg; n = 29) and 3.9% (placebo; n = 29). For more severely affected dogs (minimum CADESI ≥ 50 at baseline), there was significant reduction in mean CADESI score (29.3%, P = 0.038) only in the 200 mg/kg treatment group (n = 14). In conclusion, this study demonstrates that Phytopica^TM is an effective nonsteroidal treatment for canine AD. Funding: Phytopharm plc.     

The Effect of Pasteurella haemolytica A2 Infection on Phagocytosis Efficiency of Caprine Broncho‐Alveolar Macrophages

An experiment was designed to study the in vivo effect of Pasteurella haemolytica A2 infection on the phagocytosis activity of caprine broncho‐alveolar macrophages and the extent of pneumonic lesions. Twelve healthy local Kacang goats, about 7 months of age, were divided into two groups of six. Goats in group 1 were inoculated intratracheally with 4 ml inoculum containing 2.8 × 10⁹ colony‐forming units (CFU)/ml of Staphylococcus aureus. Goats in group 2 were inoculated intratracheally with 4 ml of inoculum containing 9.5 × 10⁸ CFU/ml of Pasteurella haemolytica A2 isolated earlier from pneumonic lungs of goat. At intervals of 3 and 7 days post‐challenge five goats from each group were killed and the lungs were washed with sterile phosphate‐buffered saline. Smears were prepared from the lung washing fluid and the number of macrophages with phagocytic activity was determined. At day 3 post‐infection, goats of both groups showed a similar pattern of pneumonic lesion. The lung washing fluid of goats in group 2 was found to contain numerous neutrophils and macrophages. Goats in group 2 showed significantly (P < 0.05) higher extent of lung lesions than group 1. Similarly, the average extent of lung lesions was significantly (P < 0.05) more severe in group 2 at day 7 post‐infection. The lung washing fluid contained mostly macrophages. The phagocytic activity following S. aureus infection was more efficient and significantly (P < 0.01) higher compared with infection by P. haemolytica A2. There were weak correlations between the extent of pneumonic lesion and the phagocytic activity. Thus, goats with poor phagocytic activity were likely to develop more extensive lung lesions.     

Bacterial and fungal colonisation of peripheral intravenous catheters in dogs and cats

Objectives : The purposes of this study were to determine the prevalence of intravenous catheter colonisation in a routine clinical setting, to identify pathogens involved and to explore factors associated with an increased risk of colonisation. Methods : A prospective study of 100 peripherally placed intravenous catheters from 13 cats and 78 dogs was conducted. The distal two‐thirds were removed and submitted for bacterial and fungal cultures. Antimicrobial susceptibility of each isolate was determined. Results : Nineteen peripheral catheters were positive for microbiologic culture from 14 animals. Twenty organisms were isolated among which Staphylococcus species was the most common. Isolates displayed lower levels of resistance against the antimicrobial agents amoxicillin‐clavulanate, cephalosporins and gentamicin than against other agents tested. Major risk factors predisposing to catheter‐related colonisation included dextrose infusion, duration of catheter placement, local complications and immunosuppressive diseases or drugs. Clinical Significance : In a routine clinical setting, the prevalence of microbial colonisation of peripheral intravenous catheters is comparable to that found in an intensive care unit. However, consequences on morbidity and mortality rates differ.     

Relative oral bioavailability of microgranulated amoxicillin in pigs

A new microgranulated formulation of amoxicillin trihydrate for in-feed medication was developed using a lipogelled matrix. Its relative bioavailability was compared with powdered drug in pigs and an assessment was made to determine whether therapeutic concentrations were achieved. Microgranules containing 10% (MICR10) and 30% (MICR30) amoxicillin and free amoxicillin trihydrate powder (reference, AMX) were administered at dosages of 50 mg of amoxicillin/kg b.w. using a three-way-crossover design. Amoxicillin analysis in serum was performed by a sensitive high performance liquid chromatography (HPLC) method with fluorometric detection, using an extraction procedure already described for edible tissues of fish and adapted and validated for pig serum. The oral bioavailability of both microgranulated formulations was higher than that of the reference formulation [relative bioavailability (F): 153.9 +/- 58.2% for MICR10; 126.2 +/- 70.5% for MICR30] and the area under the concentration-time curve (AUC) values of MICR10 and AMX formulations were significantly different (P < 0.05). Differences between the mean maximum concentration (Cmax), time of Cmax (tmax) and mean residence time (MRT) of the drug formulations were not significant. Microgranulated amoxicillin is suitable for in-feed administration to pigs and, because of its higher oral bioavailability compared with the powdered compound, it may be more effective for the treatment of susceptible infections.     

Feline platelet counting with prostaglandin E1 on the Sysmex XT‐2000iV

Background: The large size of many feline platelets and the high frequency of platelet aggregation often results in falsely low platelet counts in this species. A combination of optical platelet counting to detect even large platelets and the use of prostaglandin E1 (PGE1) to inhibit platelet clumping may increase the accuracy of feline platelet counting. Objective: The objective of this study was to compare platelet counts in feline whole blood samples with and without the addition of PGE1 and using different analytical methods in a clinical setting. Methods: Platelet counts were determined in 10 feline patients in a referral veterinary hospital using 2 sample types (EDTA, EDTA with PGE1) and 2 methods of analysis (optical counting [PLT‐O] and impedance counting [PLT‐I]) on the Sysmex XT 2000 iV analyzer. Results: All PGE1–PLT‐O samples had platelet counts of >200 × 10⁹/L. Mean platelet count using PGE1–PLT‐O (410,256±178 × 10⁹/L) was significantly higher (P<.03) compared with PGE1–PLT‐I (256±113 × 10⁹/L), EDTA–PLT‐O (238±107 × 10⁹/L), and EDTA–PLT‐I (142±84 × 10⁹/L) methods. Depending on the method, platelet counts in 2 to 7 of 10 cats were <200 × 10⁹/L when PGE1‐PLT‐O was not used. A slightly increased platelet count in response to treatment of a feline patient with thrombocytopenia would have been missed without use of PGE1–PLT‐O. Conclusions: Using PLT‐O analysis on EDTA samples containing PGE1 provides higher, and therefore likely more accurate, feline platelet counts in a clinical setting.