In vitro efficacy of a topical antimicrobial mousse and shampoo at proximal and distal hair locations against Staphylococcus pseudintermedius and Staphylococcus schleiferi.

BACKGROUND: Topical therapy is essential in assisting with the resolution of pyoderma. OBJECTIVES: (i) Evaluate the in vitro efficacy and residual activity of two different hair segments treated with shampoo and mousse against meticillin-sensitive and meticillin-resistant staphylococci; (ii) compare proximal and distal hair portions treated with the products and (iii) describe a new disc diffusion method for assessing residual efficacy. ANIMALS: Eleven privately owned, medium-haired dogs. MATERIALS AND METHODS: In this randomised, blinded and negatively controlled study, dogs were treated once with a 3% chlorhexidine digluconate-0.5% ophytrium shampoo on the lateral thorax, and the corresponding mousse on the opposite side. Hairs were plucked before treatment, two hours post-treatment, and day (D)2, D4, D7, D10 and D14. Hairs were weighed (0.01 g) and cut (1.0 cm) from the proximal portion, moistened with saline and placed on a sterile diffusion disc to absorb the solution. Proximal and distal hair bundles and diffusion discs were placed onto agar inoculated with an isolate of meticillin-sensitive or meticillin-resistant Staphylococcus pseudintermedius or Staphylococcus schleiferi. Inhibition zones were measured following incubation. RESULTS: Distal hairs had larger (p < 0.001) inhibition zones compared to proximal hairs. Mousse had significant differences (p < 0.05) between time points and locations for both the hair bundles and discs, while shampoo only had a significant difference (p < 0.001) between time points for the hairs. CONCLUSIONS AND CLINICAL RELEVANCE: Mousse was effective, and shampoo was only minimally effective in inhibiting bacterial growth in vitro, with the greatest effect occurring at the two hours time point. The distal hair shafts had greater inhibition.

Burkholderia gladioli deep pyoderma in a dog secondary to immunosuppressive ciclosporin and prednisone therapy.

A dog presented with deep pyoderma on the paw, following treatment with ciclosporin and prednisone for immune-mediated haemolytic anaemia. Cytological evaluation, skin biopsy, aerobic culture, next-generation DNA sequencing and PCR were used to detect the first reported case of Burkholderia gladioli in a dog.

Efficacy of verdinexor for the treatment of naïve canine epitheliotropic cutaneous T-cell lymphoma: An open-label pilot study.

BACKGROUND: Verdinexor (Laverdia-CA1; Dechra Veterinary Products), a selective inhibitor of nuclear export, has been utilised for treatment of non-Hodgkin T-cell lymphoma in dogs. However, the efficacy of verdinexor has not been evaluated for cutaneous epitheliotropic T-cell lymphoma (CETL). HYPOTHESIS/OBJECTIVES: To evaluate the efficacy of verdinexor for the treatment of CETL. ANIMALS: Eight client-owned animals with CETL. MATERIALS AND METHODS: Patients received between 1.28 and 1.45 mg/kg verdinexor per os twice weekly with a minimum of 72 h between doses until disease progression or voluntary withdrawal. Adjunctive therapy with lokivetmab or prednisone was permitted after Day (D)14. Assessment of clinical lesions (canine Response Evaluation Criteria in Solid Tumors [cRECIST v1.0] and novel Canine Epitheliotropic Lymphoma Extent and Severity Index [CELESI]), pruritus (Visual Analog Scale) and treatment efficacy (owner global assessment of treatment efficacy [OGATE]) were evaluated every 14 days for 3 months, then monthly thereafter (mean 70 ± 43.4 days). RESULTS: Seventy-five percent of patients achieved complete response, partial response or stable disease. The mean time to disease progression was 56 ± 41 days. There was a significant reduction (p = 0.026) in total CELESI score when the lowest score for each dog was compared to their score at D0. Verdinexor did not significantly reduce pruritus at any time point (p = 0.45), including when given as a monotherapy or concurrently with lokivetmab ± glucocorticoids. On D28, 75% of owners rated response to treatment as 'fair' to 'excellent'. The most common adverse effects included weight loss, inappetence, vomiting and lethargy. CONCLUSIONS AND CLINICAL RELEVANCE: Verdinexor could be considered a safe, palliative treatment for canine CETL.

The use of oclacitinib compared to azathioprine in the management of canine pemphigus foliaceus: A retrospective analysis.

BACKGROUND: Oclacitinib (Apoquel; Zoetis) has been reported to be beneficial for treating immune-mediated disorders. HYPOTHESIS/OBJECTIVES: This retrospective study evaluates in which group of dogs [oclacitinib (OC) or azathioprine (AZ)] remission of pemphigus foliaceus (PF) was more effectively achieved with matched induction dosing of glucocorticoids; it further evaluates which group had a higher glucocorticoid-sparing effect. ANIMALS: Review of 30 medical records of dogs diagnosed with PF presented to a private practice dermatological service. MATERIALS AND METHODS: Retrospective analysis of dogs diagnosed with PF and treated with OC or AZ in combination with glucocorticoids. RESULTS: There was no significant difference in the ability to induce remission between AZ and OC groups. In the AZ group, 13 of 15 dogs went into some type of remission (partial or complete), compared with 11 of 15 in the OC group. There was no significant difference between the two groups for the glucocorticoid-sparing effect. The AZ group had an average reduction of 77.9% from the induction glucocorticoid dose, and OC group had an average reduction of 64.4%. One of 15 patients in the AZ group and three of 15 patients in the OC group had a 100% reduction of the glucocorticoid dose. CONCLUSIONS AND CLINICAL RELEVANCE: These results indicate that OC can be considered as a treatment option for canine PF.

Modified rush venom immunotherapy in dogs with Hymenoptera hypersensitivity.

BACKGROUND: Hymenoptera envenomation occurs frequently in people and dogs and can trigger anaphylaxis. Venom immunotherapy (VIT) is the only preventive treatment for Hymenoptera hypersensitivity and is indicated for people with severe adverse reactions to insect stings. Rush VIT is an accelerated VIT protocol in people. This has not been reported in dogs. OBJECTIVES: The objective of the study was to evaluate the safety of modified rush VIT. ANIMALS: Twenty client-owned dogs with Hymenoptera hypersensitivity based on a history of adverse reactions to Hymenoptera envenomation and a positive intradermal test to honey bee and/or paper wasp venom. MATERIALS AND METHODS: Dogs received incremental doses of venom via subcutaneous injection one day per week for three consecutive weeks until the maintenance dose was achieved. Vital signs were recorded every 30 min prior to venom administration. Adverse reactions were categorised as localised or grade I-IV systemic reactions. RESULTS: Nineteen of 20 dogs (95%) completed rush VIT. One dog experienced a grade III systemic adverse reaction and was withdrawn from the study. No adverse reactions occurred in 10 of 20 dogs (50%). Localised and grade I-II systemic reactions occurred in nine of 20 dogs (45%), including nausea (n = 5), injection site pruritus (n = 3) and diarrhoea and lethargy (n = 1). CONCLUSIONS AND CLINICAL RELEVANCE: Modified rush VIT in dogs was well-tolerated and should be considered for dogs with Hymenoptera hypersensitivity. Larger studies are needed to evaluate the efficacy of VIT in dogs for preventing hypersensitivity reactions to insect stings.

In vitro efficacy of 0.2% and 0.4% sodium oxychlorosene against meticillin-resistant Staphylococcus pseudintermedius.

BACKGROUND: There is a need for alternative topical therapies as a consequence of the increased prevalence of meticillin-resistant Staphylococcus pseudintermedius (MRSP) skin infections in dogs. Sodium oxychlorosene has been used as a topical antibacterial agent in human medicine since 1955. OBJECTIVES: To determine whether 0.2% and 0.4% sodium oxychlorosene solutions have a bactericidal effect (>3-log reduction) on MRSP strains isolated from canine skin infections. METHODS AND MATERIALS: A genetically heterogeneous collection of MRSP isolates from dogs was assembled from laboratories across the United States. Time-kill assays were performed with 0.2% and 0.4% sodium oxychlorosene on a 0.5 McFarland standard [approximately 108 colony-forming units (cfu/ml)] suspension of each strain. The average bacterial counts (cfu/ml) of each MRSP strain then were determined at 5, 10, 20 and 60 s after exposure to sodium oxychlorosene; cfu/ml data were converted to log10 scale to calculate microbial reduction. RESULTS: The average bacterial counts following exposure to the 0.2% solution at 5, 10, 20 and 60 s were 6.94 × 104 , 5.63 × 103 , 2.96 × 102 and 1.48 × 102  cfu/ml, respectively. For the 0.4% solution, the average bacterial count at 5 s was 2.12 × 103  cfu/ml. No bacterial growth was observed for any MRSP strain by 10 s. The greatest reduction in cfu/ml occurred within 5 s following exposure to each solution 3.4-log and 4.9-log reduction for 0.2% and 0.4%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: 0.2% and 0.4% sodium oxychlorosene solutions have a bactericidal effect (>99.9% reduction) against MRSP in vitro. Further in vivo studies are necessary to determine whether it is an appropriate alternative therapy for canine pyoderma.

Evaluation of clonality from multiple anatomic sites in canine epitheliotropic T cell lymphoma.

BACKGROUND: Canine epitheliotropic cutaneous T-cell lymphoma (eCTCL) is thought to represent a disease homologue to human mycosis fungoides (MF). In human MF, neoplastic cells are phenotypically consistent with resident effector memory T cells, a population that remains for an extended period within tissue without circulating. Dogs with eCTCL often present with lesions in multiple locations, raising the question of whether the neoplasm is of the same T-cell subpopulation or not. OBJECTIVES: To characterize the antigen receptor gene rearrangements of lymphocytes from skin and blood of dogs with eCTCL to determine if neoplastic clones are identical. ANIMALS: Fourteen dogs with eCTCL. MATERIALS AND METHODS: Histological and immunohistochemical examination, and PCR for antigen receptor rearrangement (PARR) for T-cell receptor gamma (TRG) performed on multiple cutaneous biopsy samples and blood. RESULTS: All skin biopsies contained cluster of differentiation (CD)3-positive neoplastic lymphocytes. Within individual dogs, all skin biopsies revealed identical TRG clonality profiles, suggesting that the same neoplastic clone was present in all sites. In the blood, a matching clone was found in six of 14 dogs, a unique clone was observed in nine of 14 dogs, and no clone was detected in two of 14 dogs. CONCLUSIONS: These findings show that canine eCTCL lesions in multiple locations harbour the same neoplastic clone, neoplastic lymphocytes do not remain fixed to the skin and instead can circulate via blood, differing clones can be identified in skin versus blood, and circulating neoplastic cells can be detected without lymphocytosis.

Contexte - On pense que le lymphome T cutané épithéliotrope canin (eCTCL) représente une maladie homologue au mycosis fongoïde (MF) humain. Dans le MF humain, les cellules néoplasiques sont phénotypiquement compatibles avec les cellules T mémoire effectrices résidentes, une population qui reste pendant une période prolongée dans les tissus sans circuler. Les chiens atteints d'eCTCL présentent souvent des lésions à plusieurs endroits, ce qui soulève la question de savoir si le néoplasme appartient ou non à la même sous-population de lymphocytes T. Objectifs - Caractériser les réarrangements du gène du récepteur antigénique des lymphocytes de la peau et du sang des chiens atteints d'eCTCL afin de déterminer si les clones néoplasiques sont identiques. Animaux - Quatorze chiens avec eCTCL. Matériels et méthodes - Examen histologique et immunohistochimique, et PCR pour le réarrangement des récepteurs antigéniques (PARR) pour le récepteur gamma des lymphocytes T (TRG) effectués sur plusieurs échantillons de biopsie cutanée et de sang. Résultats - Toutes les biopsies cutanées contenaient des amas de lymphocytes néoplasiques positifs à la différenciation (CD)3. Chez les chiens individuels, toutes les biopsies cutanées ont révélé des profils de clonalité TRG identiques, suggérant que le même clone néoplasique était présent dans tous les sites. Dans le sang, un clone correspondant a été trouvé chez six des 14 chiens, un clone unique a été observé chez neuf des 14 chiens et aucun clone n'a été détecté chez deux des 14 chiens. Conclusions - Ces résultats montrent que les lésions eCTCL canines à plusieurs endroits abritent le même clone néoplasique, les lymphocytes néoplasiques ne restent pas fixés à la peau et peuvent plutôt circuler par le sang, différents clones peuvent être identifiés dans la peau par rapport au sang, et les cellules néoplasiques circulantes peuvent être détecté sans lymphocytose.

Introducción- se cree que el linfoma epiteliotrópico cutáneo de células T canino (eCTCL) representa una enfermedad homóloga a la micosis fungoide (MF) humana. En la MF humana, las células neoplásicas son fenotípicamente consistentes con las células T de memoria efectoras residentes, una población que permanece durante un período prolongado dentro del tejido sin circular. Los perros con eCTCL a menudo presentan lesiones en múltiples ubicaciones, lo que plantea la cuestión de si la neoplasia es de la misma subpoblación de células T o no. Objetivos- caracterizar los reordenamientos del gen del receptor de antígeno de los linfocitos de la piel y la sangre de perros con eCTCL para determinar si los clones neoplásicos son idénticos. Animales- catorce perros con eCTCL. Materiales y métodos - Examen histológico e inmunohistoquímico, y PCR para el reordenamiento del receptor de antígeno (PARR) para el receptor de células T gamma (TRG) realizado en múltiples muestras de biopsia cutánea y sangre. Resultados- todas las biopsias de piel contenían linfocitos neoplásicos positivos para grupos de diferenciación (CD)3. Dentro de perros individuales, todas las biopsias de piel revelaron perfiles de clonalidad de TRG idénticos, lo que sugiere que el mismo clon neoplásico estaba presente en todos los sitios. En la sangre, se encontró un clon compatible en seis de 14 perros, se observó un clon único en nueve de 14 perros y no se detectó ningún clon en dos de 14 perros. Conclusiones- estos hallazgos muestran que las lesiones de eCTCL canino en múltiples ubicaciones albergan el mismo clon neoplásico, los linfocitos neoplásicos no permanecen fijados a la piel y, en cambio, pueden circular a través de la sangre, se pueden identificar diferentes clones en la piel versus la sangre y las células neoplásicas circulantes pueden ser identificadas sin presencia de linfocitosis.

Contexto - Acredita-se que o linfoma epiteliotrópico cutâneo de células T canino (eCTCL) representa uma doença análoga à micose fungoide (MF) humana. Na MF humana, as células neoplásicas são fenotipicamente consistentes com células T efetoras de memória residentes, uma população que permanece por um período extenso no tecido sem entrar na circulação. Os cães com eCTCL frequentemente apresentam lesões em múltiplos locais, levantando a questão de se a neoplasia é da mesma subpopulação de células T ou não. Objetivos - Caracterizar os rearranjos dos genes receptores de antígenos dos linfócitos da pele e do sangue de cães com eCTCL para determinar se os clones neoplásicos são idênticos. Animais - Quatorze cães com eCTCL. Materiais e métodos - Exame histológico e imunohistoquímico, e PCR para rearranjo de receptor de antígeno (PARR) para o receptor Gama de células T (TRG) realizado em múltiplas amostras de biópsia cutânea e sangue. Resultados - Todas as biópsias cutâneas continham clusters de diferenciação linfócitos T (CD)3- positivos. Entre os indivíduos, todas as biópsias cutâneas revelaram perfis de clonalidade de TGR idênticos em seis dos 14 cães, sugerindo que a mesma célula neoplásica estava presente em todos os locais. No sangue, um clone correspondente foi encontrado em seis dos 14 cães, um clone único foi observado em nove dos 14 cães e nenhum clone foi detectado em dois dos 14 cães. Conclusões - Estes achados demonstraram que as lesões de eCTCL em múltiplos locais possuem o mesmo clone neoplásico, linfócitos neoplásicos não permanecem fixos na pele e podem circular por via sistêmica , diversos tipos de clones podem ser identificados na pele versus sangue, e as células neoplásicas circulantes podem ser detectadas sem linfocitose.

Evaluation of the use of paired modified Wright's and periodic acid Schiff stains to identify microbial aggregates on cytological smears of dogs with microbial otitis externa and suspected biofilm.

BACKGROUND: Micro-organisms associated with canine otitis externa (OE) may cause biofilm-associated infections (BAI). A key component of biofilm is microbial aggregate and extracellular polymeric substance (EPS). Periodic acid Schiff (PAS) can stain polysaccharide EPS in human otitis media with effusion, but this has not been tested in canine OE. There is no cytological definition for microbial aggregate, and definitive methods for identifying BAI in a clinical setting in canine OE have not been defined. OBJECTIVES: To establish whether PAS stain can identify polysaccharide matrix on cytological smears; and to determine the reproducibility of identification of microbial aggregates within a discrete area of stained matrix, using paired modified Wright's and PAS-stained smears. ANIMALS: Forty privately-owned dogs presenting to a dermatological referral practice. METHODS AND MATERIALS: In this prospective, cross-sectional study, three investigators independently and blindly classified 40 paired modified Wright's-PAS slide sets into groups: aggregate-associated infection (AAI) and non-AAI (n = 27); and control (n = 13). Agreement between investigators for presence of AAI was measured using Fleiss' kappa statistic (FK). Agreement between investigators and dermatologists for presence of AAI upon cytological evaluation, and suspected BAI based on clinical examination, was measured using Cohen's kappa statistic. RESULTS: The matrix was confirmed to stain PAS-positive. Interinvestigator agreement for AAI was very good using PAS (0.82 FK) and fair using modified-Wright's (MW) (0.33 FK). Reproducible cytological features associated with AAI were the presence of: three or more distinct aggregates (0.76 FK); discrete areas of PAS-positive matrix (0.70 FK); and the presence of high-density material (0.70 FK) using PAS stain. CONCLUSION: PAS can stain the extracellular matrix on otic smears, and a novel protocol for reproducible identification of cytological features such as microbial aggregates has been established.

Use of a tilapia skin xenograft for management of a large bite wound in a dog.

A 13-year-old neutered male miniature dachshund suffered ~30% total skin loss following an attack by another dog. After numerous failed attempts at wound management and closure, the wound was successfully healed by epithelialization using tilapia skin grafts. At each tilapia skin graft placement, the wound bed appeared pink, clean, and healthy with excellent progression of epithelialization at all edges. With use of the tilapia grafts, epithelialization occurred at a rate of 1.76 mm/day. As a result, the wound reached complete closure by epithelialization with no evidence of wound contracture in 102 days. Key clinical message: Tilapia skin grafts were successfully used for management of a large bite wound in a dog and may promote accelerated epithelialization in full thickness skin wounds.

Utilisation d'une xénogreffe de peau de tilapia pour la prise en charge d'une morsure importante chez un chien. Un teckel miniature mâle castré de 13 ans a subi une perte totale de peau d'environ 30 % à la suite d'une attaque par un autre chien. Après de nombreuses tentatives infructueuses de gestion et de fermeture de la plaie, la plaie a été cicatrisée avec succès par épithélialisation à l'aide de greffes de peau de tilapia. À chaque placement de greffe de peau de tilapia, le lit de la plaie apparaissait rose, propre et sain avec une excellente progression de l'épithélialisation sur tous les bords. Avec l'utilisation des greffes de tilapia, l'épithélialisation s'est produite à un taux de 1,76 mm/jour. En conséquence, la plaie a atteint une fermeture complète par épithélialisation sans signe de contracture de la plaie en 102 jours.Message clinique clé :Les greffes de peau de tilapia ont été utilisées avec succès pour la gestion d'une grande plaie de morsure chez un chien et peuvent favoriser une épithélialisation accélérée dans les plaies cutanées de pleine épaisseur.(Traduit par Dr Serge Messier).

Diagnosis and treatment of demodicosis in dogs and cats: Clinical consensus guidelines of the World Association for Veterinary Dermatology.

BACKGROUND: Demodicosis is a common disease in small animal veterinary practice worldwide with a variety of diagnostic and therapeutic options. OBJECTIVES: To provide consensus recommendations on the diagnosis, prevention and treatment of demodicosis in dogs and cats. METHODS AND MATERIALS: The authors served as a Guideline Panel (GP) and reviewed the literature available before December 2018. The GP prepared a detailed literature review and made recommendations on selected topics. A draft of the document was presented at the North American Veterinary Dermatology Forum in Maui, HI, USA (May 2018) and at the European Veterinary Dermatology Congress in Dubrovnik, Croatia (September 2018) and was made available via the World Wide Web to the member organizations of the World Association for Veterinary Dermatology for a period of three months. Comments were solicited and responses were incorporated into the final document. CONCLUSIONS: In young dogs with generalized demodicosis, genetic and immunological factors seem to play a role in the pathogenesis and affected dogs should not be bred. In old dogs and cats, underlying immunosuppressive conditions contributing to demodicosis should be explored. Deep skin scrapings are the diagnostic gold standard for demodicosis, but trichograms and tape squeeze preparations may also be useful under certain circumstances. Amitraz, macrocyclic lactones and more recently isoxazolines have all demonstrated good efficacy in the treatment of canine demodicosis. Therapeutic selection should be guided by local drug legislation, drug availability and individual case parameters. Evidence for successful treatment of feline demodicosis is strongest for lime sulfur dips and amitraz baths.

A pilot study on the comparative minimum inhibitory and mutant prevention concentration values for moxifloxacin and pradofloxacin against canine and human isolates of Staphylococcus pseudintermedius and S. schleiferi.

BACKGROUND: Moxifloxacin is a fourth-generation fluoroquinolone (FQ) that is approved for use in people to treat a variety of infections. Some veterinary microbiology laboratories report moxifloxacin in culture and sensitivity profiles for Staphylococcus pseudintermedius and S. schleiferi albeit using Clinical & Laboratory Standards Institute (CLSI) breakpoints for S. aureus. Previous studies have shown that S. aureus breakpoints can mischaracterize S. pseudintermedius susceptibility to various drugs. Pradofloxacin is a third generation veterinary FQ with a similar mechanism of action and spectrum of activity to moxifloxacin; however, the dose format (25 mg/mL solution) available in the USA may limit its practical use in large dogs. OBJECTIVE: To determine the minimum inhibitory concentration (MIC), mutant prevention concentration (MPC) and mutant selection window (MSW) of moxifloxacin and pradofloxacin for isolates of S. pseudintermedius and S. schleiferi. METHODS AND MATERIALS: Pulsed-field gel electrophoresis was performed to establish that each bacterial isolate selected for testing represented an unique strain. The MIC, MPC and MSW for moxifloxacin and pradofloxacin were determined from 60 strains of S. pseudintermedius and seven strains of S. schleiferi. RESULTS: The MIC and MPC ranges of moxifloxacin and pradofloxacin for meticillin-susceptible S. pseudintermedius were similar. However, MIC and MPC ranges were much wider and resistance to both drugs was more common for meticillin-resistant strains of S. pseudintermedius and S. schleiferi. CONCLUSIONS AND CLINICAL IMPORTANCE: The narrow MSW of these drugs may reduce the risk of selecting for antibiotic-resistant subpopulations. Pharmacokinetic, pharmacodynamic and safety studies are needed.

The in vitro antibacterial activity of the anthelmintic drug oxyclozanide against common small animal bacterial pathogens.

BACKGROUND: Repurposing existing drugs is one approach to address the growing concerns of multi-drug resistant bacterial pathogens in veterinary medicine. Oxyclozanide is in the anthelmintic drug class salicylanilide, which has been used primarily as a treatment and preventative for Fasciola hepatica in ruminants. The antimicrobial activity of oxyclozanide has been studied in human medicine; its activity against common small animal bacterial pathogens such as Staphylococcus pseudintermedius has yet to be determined. OBJECTIVE: The aim of this study was to measure and establish the minimum inhibitory concentration (MIC) and mutant prevention concentration (MPC) of oxyclozanide against S. pseudintermedius and other common small animal bacterial pathogens. METHODS AND MATERIALS: The MIC and MPC of oxyclozanide were determined from eighteen meticillin sensitive S. pseudintermedius (MSSP) isolates and eleven meticillin-resistant S. pseudintermedius (MRSP), as well as single isolates of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Enterococcus faecalis. RESULTS: The MIC of the eighteen meticillin-sensitive S. pseudintermedius isolates was 0.5-1 µg/mL and the MPC ranged between 16 and 32 µg/mL. The MIC of the eleven meticillin-resistant strains of S. pseudintermedius ranged from 0.5 to 2 µg/mL with a MPC ranging between 16 and 32 µg/mL. A single isolate of meticillin-resistant S. aureus (MRSA) had an MIC of 1 µg/mL and MPC 16 µg/mL. No inhibition of growth was seen at the concentrations tested for bacterial isolate strains E. coli, P. aeruginosa and E. faecalis. CONCLUSION AND CLINICAL IMPORTANCE: Oxyclozanide demonstrated in-vitro antibacterial activity against meticillin-resistant S. pseudintermedius. Further studies are needed to evaluate the potential use of oxyclozanide as a topical bactericidal agent.

Persistent papilloma treated with cryotherapy in three dogs.

BACKGROUND: Canine papillomaviruses can affect the mucous membranes and skin of young, old and immunocompromised dogs. Most lesions regress spontaneously over a four to eight week interval; however, in some cases the lesions may persist or progress. Cryotherapy is used as a treatment for papillomavirus induced lesions in veterinary practice but there is limited published evidence regarding its use. OBJECTIVES: To describe the history, lesions and treatment outcomes of three dogs with persistent viral papillomas treated with cryotherapy. ANIMALS: Three client owned dogs. METHODS: Canine viral papilloma lesions were treated with five to six freeze-thaw cycles using liquid nitrogen cryotherapy. RESULTS: All lesions in each case resolved with cryotherapy treatment. Two cases required one treatment and one case required two treatment courses. CONCLUSIONS AND CLINICAL IMPORTANCE: The apparent resolution of these papilloma lesions with cryotherapy suggests that this may be a useful treatment intervention for persistent canine papilloma lesions. Spontaneous resolution may still have taken place; consequently, large scale clinical trials are required to demonstrate unequivocally that this mode of therapy, as with other therapeutic modalities, is really effective in the treatment of canine papillomatosis.

Comparison of the intradermal irritant threshold concentrations of nine allergens from two different manufacturers in clinically nonallergic dogs in the USA.

BACKGROUND: The intradermal irritant threshold concentration for many allergens is unknown. OBJECTIVE: To determine the intradermal irritant threshold concentration (ITC) of nine allergens from two different manufacturers. ANIMALS: Twenty privately owned clinically nonallergic dogs. METHODS: Alternaria, cat dander, Dermatophagoides farinae, Chenopodium album (lamb's quarter), Xanthium strumarium (cocklebur), Prosopis glandulosa (mesquite), Morus alba (white mulberry), Cynodon dactylon (Bermuda grass) and Phleum pretense (Timothy grass) from two manufacturers (ALK; Round Rock, TX, USA and Greer® Laboratories; Lenoir, NC, USA) were injected intradermally at two dilutions and at 15 and 30 min evaluated subjectively (1-4) and objectively (horizontal wheal diameter) by two blinded investigators. A subjective score of 3 or 4 by either investigator at either timed reading was considered positive. If both concentrations resulted in positive reactions, two additional dilutions were performed. The ITC was defined as the lowest tested concentration that elicited a positive reaction in ≥10% of animals. RESULTS: The ITCs were Alternaria >2,000 PNU/mL; cat dander 750 PNU/mL (ALK) and 2,000 PNU/mL (Greer® ); D. farinae <1:10,000 w/v; C. album <6,000 PNU/mL; X. strumarium <6,000 PNU/mL; P. glandulosa <500 PNU/mL; M. alba <6,000 PNU/mL; C. dactylon <10,000 PNU/mL (ALK) and <6,000 PNU/mL (Greer® ); and P. pretense <6,000 PNU/mL. CONCLUSIONS AND CLINICAL SIGNIFICANCE: There were significant differences in subjective scoring and objective measurement between manufacturers for Alternaria, cat dander and P. pretense. Results revealed significant positive correlation between subjective scoring and objective measurement for each time, investigator and manufacturer separately.

Evaluation of cytology collection techniques and prevalence of Malassezia yeast and bacteria in claw folds of normal and allergic dogs.

BACKGROUND: Canine bacterial and Malassezia paronychia are common secondary complications of atopic dermatitis and adverse food reactions. HYPOTHESIS/OBJECTIVES: The aim of this study was to compare three different sampling methods for claw fold cytology and to evaluate the numbers of bacteria, Malassezia yeast and inflammatory cells. ANIMALS: Sixty client-owned dogs were classified into three groups: (A) normal dogs; (B) allergic dogs with no clinical evidence of claw disease (brown staining, erythema, swelling, crusts or exudates); and (C) allergic dogs with clinical paronychia. METHODS: A prospective, blinded, split-plot study design was used. Claw folds from each dog were sampled using either a toothpick, tape preparation or direct impression smear. Slides were evaluated by two investigators for inflammatory cells, nuclear streaming, debris, corneocytes, yeast, intracellular (IC) cocci, extracellular (EC) cocci, IC rods and EC rods. For each parameter, data were compared between groups and between methods. Inter-reader agreements were calculated. RESULTS: Group C had significantly higher values of EC cocci and corneocytes than Groups A or B. Although Malassezia organisms were more prevalent in allergic dogs than normal dogs, the counts were not significantly different. There were significantly higher numbers of Malassezia organisms (P = 0.0016) and EC cocci (P = 0.0106) retrieved from samples collected with a toothpick compared to other methods. Tape preparations were associated with significantly more debris and corneocytes (both P < 0.0001) and impression smears with significantly more nuclear streaming (P = 0.0468). CONCLUSIONS AND CLINICAL IMPORTANCE: Sample collection using a toothpick optimizes the value of cytological results when sampling allergic dogs with clinical paronychia.

Residual antibacterial activity of canine hair treated with topical antimicrobial sprays against Staphylococcus pseudintermedius in vitro.

BACKGROUND: Topical antimicrobial therapy is increasingly important in the treatment of canine pyoderma as the incidence of multidrug resistance has risen. However, little information is reported on the persistence of activity of topical antimicrobial products. OBJECTIVE: To determine the residual antibacterial activity of canine hairs treated with antimicrobial sprays. ANIMALS: Twelve privately owned dogs with no history of dermatological disease. METHODS: Dogs were treated once with four different spray products [(A) 1% chlorhexidine digluconate, (B) 2% miconazole nitrate, 2% chlorhexidine gluconate, tromethamine USP/disodium EDTA (TrizEDTA), (C) 3% chlorhexidine gluconate, phytosphingosine salicyloyl and (D) 4% chlorhexidine gluconate, TrizEDTA] in separate 5 × 5 cm sections on the trunk. Hairs were collected via shaving before, one hour after and 2, 4, 7 and 10 days after treatment. Hairs were incubated on agar plates streaked with Staphylococcus pseudintermedius for 24 h and the bacterial growth inhibition zone around the hairs was measured. RESULTS: There were significant overall treatment and day (P < 0.0001) differences in inhibition zones. The largest zones of inhibition were from hairs treated with spray B, followed by sprays D, C and A, respectively. All sprays demonstrated residual antimicrobial activity for the ten days evaluated. CONCLUSIONS AND CLINICAL SIGNIFICANCE: Results suggest that the efficacy of an antimicrobial spray is dependent on both the concentration and combination of active ingredients. Several ingredient profiles appear to effectively inhibit S. pseudintermedius growth for at least 10 days, which may be beneficial in the treatment of canine pyoderma.

Clinical efficacy of low-level laser therapy on localized canine atopic dermatitis severity score and localized pruritic visual analog score in pedal pruritus due to canine atopic dermatitis.

BACKGROUND: Canine atopic dermatitis is a genetically predisposed inflammatory skin disease often requiring multimodal treatment. There is a need to find further low-risk adjunctive therapies. HYPOTHESIS/OBJECTIVES: To evaluate the localized effect of low-level laser therapy (LLLT) on the paws of dogs with atopic dermatitis using a localized canine atopic dermatitis severity score (LCADSS) and owner localized pruritic visual analog score (LPVAS) in comparison to treatment with a placebo. ANIMALS: Thirty client-owned dogs with symmetrical pedal pruritus due to canine atopic dermatitis. METHODS: Dogs were randomly assigned into two groups. In each group, one paw was treated with LLLT and one paw treated with a placebo laser (comparing either both fore- or hindpaws). Treatments were administered at 4 J/cm(2) (area from carpus/tarsus to distal aspect of digit 3) three times per week for the first 2 weeks and two times per week for the second 2 weeks. Scores were assessed for each paw at weeks 0, 2, 4 and 5. RESULTS: There were no significant differences in LCADSS or LPVAS between LLLT and placebo treatments between weeks 0 and 5 (P = 0.0856 and 0.5017, respectively). However, LCADSS and LPVAS significantly decreased from week 0 at weeks 2, 4 and 5 in both LLLT and placebo groups (P < 0.0001 for all). CONCLUSIONS AND CLINICAL IMPORTANCE: Low-level laser therapy is not an effective localized treatment for pedal pruritus in canine atopic dermatitis.

Reproducibility of a quantitative cutaneous cytological technique.

BACKGROUND: Cutaneous cytology is a valuable tool for diagnosis of canine superficial pyoderma. Current published reproducible techniques are semiquantitative. HYPOTHESIS/OBJECTIVES: The aim of this study was to evaluate the reproducibility of a quantitative method for skin surface cytology in dogs with superficial pyoderma. ANIMALS: Impression smears were collected from five normal dogs and 20 dogs with clinical and cytological evidence of superficial pyoderma. METHODS: Four investigators evaluated 10 oil immersion fields (OIF) on 25 slides, selecting fields with inflammatory cells, nuclear streaming and or keratinocytes under ×10 magnification. Investigators repeated blinded evaluations of all slides at least twice. For each OIF, polymorphonuclear leukocytes (PMNs), intracellular (IC) cocci, extracellular (EC) cocci, IC rods, EC rods and yeast were quantified. Nuclear streaming was scored as present or absent. For each parameter, within-reader and between-reader agreements were expressed by the intraclass correlation (ICC) value (≤0.20 poor, 0.21-0.40 fair, 0.41-0.60 moderate, 0.61-0.80 good and 0.81-1.00 excellent) or kappa statistic (κ). RESULTS: Reproducible parameters included: PMNs (ICC = 0.58), nuclear streaming (ICC = 0.68), EC cocci (ICC = 0.64) and IC cocci (ICC = 0.32). When qualified as present or absent, within-reader κ for IC cocci was 0.71. The method demonstrated 93% sensitivity in identifying dogs with superficial pyoderma and 51% specificity in identifying normal dogs according to established criteria. However, if criteria for normal dogs were limited to the absence of PMNs and IC bacteria, sensitivity of 64% and specificity of 98% were demonstrated. CONCLUSIONS AND CLINICAL IMPORTANCE: For several parameters, including PMNs, nuclear streaming, EC cocci and IC cocci, a reproducible, quantitative cytological technique was identified.

Concurrent short-term use of prednisolone with cyclosporine A accelerates pruritus reduction and improvement in clinical scoring in dogs with atopic dermatitis.

BACKGROUND: A randomized, unmasked, multicenter study was conducted to evaluate the rate of pruritus reduction and improvement in clinical scoring by cyclosporine A (5 mg/kg orally, once daily for 28 days) either alone (n = 25 dogs) or with concurrent prednisolone (1 mg/kg once daily for 7 days, followed by alternate dosing for 14 days; n = 23 dogs) for the treatment of atopic dermatitis in dogs. Dogs were included in the study after exclusion of other causes of pruritic dermatitis, and were assessed by dermatologists on days 0, 14 ± 1 and 28 ± 2. Assessments included: general physical examination, CADESI-03 lesion scoring, overall clinical response, evaluation of adverse events (AEs), body weight and clinical pathology (hematology, clinical chemistry and urinalysis). Owner assessments, including pruritus (visual analogue scale, VAS) and overall assessment of response were conducted every 3-4 days, either during visits to the clinic or at home. Owners reported AEs to the investigator throughout the study. RESULTS: By day 28 ± 2 both treatment groups resulted in a significant improvement of the atopic dermatitis. Both investigators and owners agreed that concurrent therapy resulted in a quicker improvement of the dogs 'overall' skin condition and of pruritus (significant reduction of pruritus by day 3-4, 72.8% improvement by day 14 ± 1), when compared to cyclosporine A alone (significant reduction of pruritus by day 7-8, 24.7% improvement by day 14 ± 1). CADESI-03 scores significantly improved in both groups by day 14 ± 1 onwards, and there were no significant differences in the scores between treatment groups at any time points. A total of 56 AEs (cyclosporine A alone = 34; concurrent therapy = 22) were reported in 33 dogs. No dogs died or stopped treatment due to an AE. The most commonly reported AEs in the cyclosporine A group were associated with the digestive tract, whilst systemic disorders were reported more frequently observed following concurrent therapy. Evaluation of body weight change and clinical pathology indices showed no overall clinically significant abnormalities. CONCLUSIONS: In dogs with atopic dermatitis, a short initiating course of prednisolone expedited the efficacy of cyclosporine A in resolving pruritus and associated clinical signs. The observed adverse events were consistent with those expected for the individual veterinary medicinal products.

Evaluation of azithromycin in systemic and toothpaste forms for the treatment of ciclosporin-associated gingival overgrowth in dogs.

BACKGROUND: Gingival overgrowth is an adverse effect of ciclosporin therapy. Azithromycin (AZI) in capsule and toothpaste form is an effective treatment for ciclosporin-associated gingival overgrowth (CsAGO) in humans. HYPOTHESIS/OBJECTIVES: To evaluate AZI in a systemic and a toothpaste form for the treatment of CsAGO in dogs. The secondary objective was to determine which treatment is more effective. ANIMALS: Thirty-six client-owned dogs with CsAGO. METHODS: Dogs were randomly assigned to the following four groups: AZI capsule; AZI toothpaste; placebo capsule; and placebo toothpaste. Treatments were for 4 weeks, and measurements of gingival sulcus depth, tooth length and subjective global scores were taken at weeks 0, 2, 4 and 8. The AZI dose was 10 mg/kg daily, and brushing (8.5% AZI) was once daily. RESULTS: There was a significant decrease in gingival sulcus depth for the AZI capsule group at week 8 and for the AZI toothpaste group at weeks 2, 4 and 8. The mean decrease in gingival sulcus depth was significantly greater in active versus placebo groups (P = 0.0356). The tooth length and subjective global scores were not significantly different for any groups. Gastrointestinal adverse events occurred in all groups, but more frequently in the AZI capsule group. CONCLUSIONS AND CLINICAL IMPORTANCE: Azithromycin improved CsAGO in only one measured parameter, gingival sulcus depth. Only one dog in the AZI capsule group had complete resolution of CsAGO. Further studies are warranted. Azithromycin capsules were associated with the most gastrointestinal adverse effects.