Carbon dioxide laser surgery for chronic proliferative and obstructive otitis externa in 26 dogs.

BACKGROUND: Some dogs with chronic otitis externa (OE) develop proliferation of the tissues surrounding the opening of the external ear canal, resulting in obstruction. Traditionally total ear canal ablation with bulla osteotomy (TECABO) has been recommended. OBJECTIVES: To evaluate the efficacy of a novel treatment using carbon dioxide (CO2 ) laser surgery and to describe the histopathological features of chronic proliferative and obstructive OE. ANIMALS: Twenty-six dogs were included, 16 with bilateral and 10 with unilateral disease (42 ears were treated). Dogs with nonpatent horizontal ear canal or macroscopic calcification of the ear canal were excluded. For histopathological evaluation, tissue samples were collected from 11 dogs (17 ears). METHODS AND MATERIALS: Hyperplastic tissue around the canal opening and within the vertical ear canal was dissected and ablated using a CO2 laser. Biopsy samples were evaluated for sebaceous and ceruminous gland hyperplasia, epidermal hyperplasia, inflammation and fibrosis. RESULTS: Following CO2 laser surgery there was a good or excellent outcome with substantial resolution of proliferative changes in 39 of 42 ears from 24 of 26 dogs. One surgery was sufficient in 21 dogs and three dogs had two surgeries. Two dogs had recurrence of proliferative tissue after one surgery and underwent TECABO. Two dogs had no recurrence of proliferative tissue after surgery, yet had persistent luminal infection and underwent TECABO. The remainder of the dogs were effectively medically managed long-term following surgery. Histologically, eight ears had a predominantly sebaceous gland response, three had a predominantly ceruminous response and six had a mixed glandular pattern. Epidermal hyperplasia, inflammation and fibrosis varied from mild to severe. CONCLUSIONS AND CLINICAL RELEVANCE: Carbon dioxide laser surgery is an effective treatment of proliferative OE causing obstruction of the ear canal opening and vertical canal, and should be considered as an alternative to TECABO whenever possible.

Treatment of canine cutaneous epitheliotropic T-cell lymphoma with oclacitinib: a case report.

Canine cutaneous epitheliotropic T-cell lymphoma (CETL) is associated with a poor prognosis and without consistently beneficial treatment options. This case report describes a 9-year-old Staffordshire bull terrier with CETL treated with oclacitinib (0.7 mg/kg twice daily), resulting in partial remission that was maintained for three months. Further studies are warranted.

Le lymphome cutané T épithéliotrope canin (CETL) est associé à un pronostic faible et sans option thérapeutique bénéfique constante. Ce cas clinique décrit un Staffordshire bull-terrier de 9 ans avec CETL traité avec oclacitinib (0,7 mg/kg deux fois par jour), résultant en une rémission partielle qui s'est maintenue trois mois. Des études supplémentaires sont nécessaires.

El linfoma epiteliotrópico cutáneo de células T canino (CETL) se asocia con un mal pronóstico y sin opciones de tratamiento consistentemente beneficiosas. Este informe de caso describe un Staffordshire bull terrier de 9 años con CETL tratado con oclacitinib (0,7 mg/kg dos veces al día), lo que resultó en una remisión parcial que se mantuvo durante tres meses. Se necesitan más estudios.

O linfoma epiteliotrópico canino de células T (CETL) está associado a um mau prognóstico e sem opções de tratamento consistentemente benéficas. Este relato de caso descreve um Staffordshire bull terrier de 9 anos de idade com CETL tratado com oclacitinib (0,7 mg/kg duas vezes ao dia), resultando em remissão parcial que foi mantida por três meses. Mais estudos são necessários.

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.

In vitro comparison of the dermal penetration of three different topical formulations containing lasalocid.

BACKGROUND: Topical antimicrobial preparations are of utmost importance in treating suspected and confirmed meticillin-resistant Staphylococcus pseudintermedius (MRSP) infections due to the increasing incidence of widespread resistance to systemic antimicrobials. Lasalocid is active against MRSP in vitro and this may become an important topical antimicrobial for the treatment of canine pyoderma. HYPOTHESIS/OBJECTIVES: To determine effects of various formulation types on penetration and retention of lasalocid applied to canine skin in vitro. ANIMALS: Normal canine skin was collected from the thorax of five dogs that had been euthanized on the basis of health and/or intractable behavioural issues. METHODS: Solution, lotion and ointment containing 2% lasalocid were applied to ex vivo canine skin. Transdermal penetration was assessed for a 24 h period and retention of lasalocid was assessed at the conclusion of the study. RESULTS: The solution had significantly higher skin retention of lasalocid and proportion of applied dose retained in skin than lotion and ointment (Tukey-Kramer Honest Significant Difference test, P < 0.01). Lasalocid could not be detected in the receptor fluid of any Franz cell at any time point. CONCLUSIONS AND CLINICAL IMPORTANCE: Lasalocid was not identified in the receptor fluid of any sample, indicating that systemic absorption of the active ingredient in vivo is unlikely. Lasalocid may be useful in the treatment of MRSP infections if in vivo studies support safety and efficacy.

Canine eosinophilic granuloma of the digits treated with prednisolone and chlorambucil.

BACKGROUND: Canine eosinophilic granuloma (CEG) is an uncommon disease. Lesions are typically located in the oral cavity and other cutaneous sites, but are rarely reported to affect the digits. The majority of cases are treated with prednisolone as a monotherapy; alternative treatment options include corticosteroids administered in combination with azathioprine, antihistamines, electrochemotherapy with bleomycin, and surgical resection. Neither chlorambucil nor laser previously have been reported as treatments. OBJECTIVES: To describe an alternative therapy for treatment of CEG; using chlorambucil in combination with prednisolone for those cases that fail to respond to prednisolone alone. The new treatment was chosen according to good clinical practice and after owner consent. ANIMALS: Two client owned dogs. METHODS: One case was initially treated with carbon dioxide laser to debulk the lesions. Both cases were treated with a combination of oral prednisolone and chlorambucil. RESULTS: Both dogs experienced rapid resolution of lesions with prednisolone and chlorambucil therapy. Case 1 remained in remission three months after withdrawing medication. Case 2 experienced relapse 10 weeks after discontinuing therapy but was well controlled on maintenance prednisolone with chlorambucil at low, well tolerated doses. CONCLUSIONS AND CLINICAL IMPORTANCE: Although CEG appears to be an uncommon disease, it should be included as a differential diagnosis for dermal, nodular lesions affecting the digits. Chlorambucil appears to be an effective and well tolerated prednisolone sparing agent for treatment of CEG. Carbon dioxide laser ablation appears to be an effective method of debulking CEGs.

Carbon dioxide laser treatment of extensive pigmented viral plaque lesions in a golden retriever dog.

BACKGROUND: Canine pigmented viral plaque (PVP) is an uncommon skin disease, associated with papillomavirus infection. Lesions are usually small (<1 cm diameter), pigmented macules to plaques on the ventral abdomen and medial thigh. ANIMALS: An 8-year-old male, neutered golden retriever dog presented with numerous dark plaques forming cohesive plaques on the ventrum extending down the medial aspect of both hind legs. The plaques were associated with significant pruritus. RESULTS: Histology confirmed a diagnosis of PVP and PCR amplified Canis familiaris papillomavirus 4 from a formalin fixed plaque sample. The PVPs were completely resolved by two courses of CO2 laser treatment. There was very minimal postoperative discomfort and no relapse or new lesion development within a 12 months follow-up period. CONCLUSIONS AND CLINICAL IMPORTANCE: Extensive PVPs have not previously been described in a golden retriever dog or previously reported to cause pruritus in dogs. Due to the large skin area involved, surgical excision was not feasible in this case. However, two rounds of treatment using laser were completely curative for both focal pedunculated and plaque-like PVP lesions. Additionally, compared to surgical excision, laser treatment is expected to result in less postoperative discomfort, reduced surgery time and fewer postoperative infections. This is the first report of successful treatment of canine PVPs using a CO2 laser. The success of this treatment in this case suggests that laser provides an excellent treatment option for extensive PVPs in dogs.

Treatment of canine generalized demodicosis using weekly injections of doramectin: 232 cases in the USA (2002-2012).

BACKGROUND: Generalized demodicosis is a severe skin disease in the dog, with limited treatment options. HYPOTHESIS/OBJECTIVES: To demonstrate that doramectin, when given at a dose rate of 0.6 mg/kg body weight, is a safe and effective treatment for generalized demodicosis in the dog. ANIMALS: Four hundred client-owned dogs diagnosed with generalized demodicosis at one general small-animal practice. Of these, 232 completed their treatment and were included in the study. METHODS: A retrospective study was carried out by searching the computerised medical records of dogs seen at one general small-animal practice in Tennessee, USA. The records of each dog with a diagnosis of generalized demodicosis, who underwent treatment using weekly injections of doramectin at a dose rate of 0.6 mg/kg body weight, were analysed. RESULTS: Remission was achieved in 94.8% of dogs treated with weekly subcutaneous injections of doramectin at a dose rate of 0.6 mg/kg body weight. Adverse events were rare with two suspected instances (0.5%) being recorded. The mean duration of treatment was 7.1 weeks. CONCLUSIONS AND CLINICAL IMPORTANCE: Doramectin given at a dose rate of 0.6 mg/kg body weight by subcutaneous injection at weekly intervals is a useful and well-tolerated treatment for generalized demodicosis in the dog.

A preliminary survey of the histopathological features of skin from the planum nasale and adjacent skin of dogs unaffected by dermatological or respiratory disease.

BACKGROUND: There is a general belief that immune system cells are present in larger numbers in the planum nasale and adjacent haired skin than in other locations in the dog. However, little published information about the normal histological appearance of the skin of this area exists. HYPOTHESIS/OBJECTIVES: The aim was to obtain information about the normal histological appearance of canine skin for specific anatomical regions of the planum nasale and the haired skin adjacent to the planum nasale. ANIMALS: Samples from three sites were obtained from the planum nasale and adjacent haired skin of 25 dogs of varying age, breed and sex, with no evidence of dermatological or respiratory disease. METHODS: Samples were analysed to determine and quantify the immune system cells present in the samples. Slides were stained with haematoxylin and eosin or toluidine blue; immunohistochemical stains for CD3 and CD79a were applied. RESULTS: Immune system cells, including lymphocytes and plasma cells, were either very rare or present in low numbers. The majority of lymphocytes were of T-cell origin, with only infrequent B cells identified. Samples contained numerous melanophages, consistent with pigmentary incontinence, regardless of the presence or absence of inflammatory cells. Mast cells and plasma cells were present in low numbers. CONCLUSIONS: Inflammatory change noted in diagnostic biopsies from this area from dogs with clinical disease is likely to be of pathological significance. However, pigmentary incontinence appears to be common at this site in clinically normal dogs without significant inflammatory cell infiltration and is therefore not necessarily of pathological significance when seen in isolation in this location.

Treatment of demodicosis in dogs: 2011 clinical practice guidelines.

BACKGROUND AND OBJECTIVES: These guidelines were written by an international group of specialists with the aim to provide veterinarians with current recommendations for the diagnosis and treatment of canine demodicosis. METHODS: Published studies of the various treatment options were reviewed and summarized. Where evidence in form of published studies was not available, expert consensus formed the base of the recommendations. RESULTS: Demodicosis can usually be diagnosed by deep skin scrapings or trichograms; in rare cases a skin biopsy may be needed for diagnosis. Immune suppression due to endoparasitism or malnutrition in young dogs and endocrine diseases, neoplasia and chemotherapy in older dogs are considered predisposing factors and should be diagnosed and treated to optimize the therapeutic outcome. Dogs with disease severity requiring parasiticidal therapy should not be bred. Secondary bacterial skin infections frequently complicate the disease and require topical and/or systemic antimicrobial therapy. There is good evidence for the efficacy of weekly amitraz rinses and daily oral macrocyclic lactones such as milbemycin oxime, ivermectin and moxidectin for the treatment of canine demodicosis. Weekly application of topical moxidectin can be useful in dogs with milder forms of the disease. There is some evidence for the efficacy of weekly or twice weekly subcutaneous or oral doramectin. Systemic macrocyclic lactones may cause neurological adverse effects in sensitive dogs, thus a gradual increase to the final therapeutic dose may be prudent (particularly in herding breeds). Treatment should be monitored with monthly skin scrapings and extended beyond clinical and microscopic cure to minimize recurrences.

Biological efficacy and stability of diluted ticarcillin-clavulanic acid in the topical treatment of Pseudomonas aeruginosa infections.

Topical compounded Timentin(®) diluted with an inactive vehicle has been reported to be effective in the treatment of otitis externa caused by Pseudomonas aeruginosa. The aims of this study were to determine the biological efficacy of Timentin(®) (ticarcillin and clavulanic acid) when diluted in the carrier vehicle Methopt(®) against P. aeruginosa and to determine the efficacy and stability of Timentin(®) aqueous stock concentrate solution. Timentin(®) stock concentrate was tested against four P. aeruginosa isolates on days 0, 7, 14, 21 and 28; then after 2, 3, 4, 5, 6, 9 and 12 months of storage at 4 or -20°C. The diluted Timentin(®)-Methopt(®) solutions were tested against all isolates after 0, 2, 4, 6, 8, 10, 12, 14, 17, 21, 24 and 28 days of storage at 24 or 4°C. Minimal inhibitory concentration (MIC) levels for all strains were determined using the broth microdilution method. The MIC of the stock solution remained relatively constant and acceptable throughout the study when stored at -20°C and was also acceptable for shorter time periods (6-9 months) when stored at 4°C. The MIC for the diluted Timentin(®)-Methopt(®) solution remained relatively constant and acceptable throughout the study for all four bacterial strains, with no difference between the solutions stored at 4 or 24°C. The results of this study indicate that storage of the Timentin(®) stock solution at -20°C does not compromise efficacy for at least 12 months and that Timentin(®) diluted in Methopt(®) was stable for 28 days when stored at either 4 or 24°C.

The Use of Insect Development Inhibitors as an Oral Medication for the Control of the Fleas Ctenocephalides felis, Ct. canis in the Dog and Cat.

Résumé- Il existe deux inhibiteurs de croissance des insectes (ICI) sous forme orale pour le contrôle des puces. Le lufénuron s'administre une fois par mois à la dose de 10 mg/kg chez le chien et 30 mg/kg chez le chat. La cyromazine s'administre quotidiennement à la dose de 10 mg/kg en association avec la diethylcarbamazine chez le chien. Aucun des deux produits n'est actif sur la puce adulte, mais cause plutôt une interruption de la production de chitine normale par différents modes d'actions spécifiques. Ceci entraine la mort des formes immatures de puces. Par conséquent, les 2 produits contrôle l'infestation par les puces adultes sur l'animal par le biais de l'élimination des formes immatures présentes dans le milieu. Il existe un délai de 6 à 8 semaines entre 1'administration d'inhibiteurs de croissance des insectes (ICI) et la reduction du nombre de puces adultes sur les animaux traités. Cette période réfractaire est due à la survie de puces immatures présentes dans le milieu avant le traitement aux ICI; elle peut être réduite si l'on démarre le traitement oral par les ICI simultanément à un traitement insecticide du milieu environnant et de l'animal. [Shipstone, M. A., Mason, K. V. The use of Insect Development Inhibitors as an oral medication for the control of the fleas Ctenocephalides felis, Ct. canis in the dog and cat (Utilisation d'inhibiteurs de croissance des insectes sous forme orale pour le contrôle des puces Ctenocephalides felis, Ct. canis chez le chien et le chat). Resumen- Existen dos inhibidores del desarrollo de insectos (ICI) para el control de pulgas. El Lefenuron se administra una vez al mes a una dosis de 10 mg × Kg-1 en perros y 30 mg × Kg-1 en gatos. La Ciromacina se administra diariamente a una dosis de 10 mg × Kg-1 en combinación con citrato de dietilcarbamacina en perros. Ninguno de estos compuestos produce efecto en pulgas adultas, sino que causa una interrupción en la producción normal de quitina por distintos mecanismos de acción. Ello causa la muerte del parásito en estadíos de inmadurez y crecimiento. Así, ambos controlan la infestación por pulgas adultas en el animal mediante la eliminación de estadíos vitales de la pulga. Existe un espacio de tiempo de 6-8 semanas entre el inicio de la aministración de ICA y la reducción del número de pulgas en animales tratados. Ésto et debido a la supervivencia de pulgas inmaduras que se encontraban en el entorno antes del inicio del tratamiento con ICI; este periodo de tiempo se puede reducir iniciando el tratamiento oral con ICI junto con tratamiento insecticida de la vivienda y sobre el animal. [Shipstone, M. A., Mason, K. V. The use of Insect Development Inhibitors as an oral medication for the control of the fleas Ctenocephalides felis, Ct. canis in the dog and cat (El uso de inhibidores del desarrollo de insectos como medicación oral para el control de las pulgas Cenocephalides felis y Ct. canis en el perro y en el gato). Abstract- There are two oral Insect Development Inhibitors (IDI) for the control of fleas. Lufenuron is administered once a month at 10 mg × kg-1 for dogs and 30 mg × kg-1 for cats. Cyromazine is administered daily at 10 mg kg-1 in combination with diethylcarbamazine citrate for dogs. Neither compound exerts an effect on the adult flea, but rather causes an interruption in normal chitin production through different specific modes of action. This causes death of the immature, developmental life stages of the flea. Thus, both control the adult flea infestation on the animal via the elimination of the environmental life stages of the flea. There is a lag phase of 6-8 weeks between the initiation of IDI administration and reduction in the number of adult fleas on the treated animals. The lag phase results from the survival of immature fleas that were present in the environment before the onset of IDI treatment; it can be reduced by initiating oral IDI treatment in combination with premise and on-animal insecticide treatments.

Diagnosis of canine claw disease - a prospective study of 24 dogs.

The aetiology of claw disease in 24 dogs exhibiting only claw disease was investigated with cytologic examination of claw exudate, complete blood count (CBC), serum biochemistry panel, urinalysis, total thyroxine (tT4) concentration, antinuclear antibody (ANA) titre, bacterial culture and sensitivity testing, fungal culture, histopathology of claw biopsy samples and elimination diet. Abnormalities on the CBC, serum biochemistry panel and urinalysis were minor and nonspecific. Total T4 concentrations were within the normal laboratory reference range. Fungal cultures and ANA titres were negative in all dogs. A bacterial infection was present in approximately half of the dogs. On histological examination of claw tissue, a cell-poor or cell-rich interface onychitis was seen in all but one dog. Evidence for an adverse reaction to food was present in four dogs. One dog responded completely to antibiotic therapy. Interface onychitis seems to be a histological reaction pattern of the claw matrix in the dog with various possible underlying aetiologies. In dogs with claw disease as the only clinical sign, the recommended initial diagnostic evaluation includes cytologic examination, bacterial culture and sensitivity, claw biopsy and an elimination diet.