Local treatment for canine anal sacculitis: A retrospective study of 33 dogs.

BACKGROUND: Little information has been published regarding treatment of canine anal sacculitis (AS). OBJECTIVES: Primary objective: determine the outcomes of AS local treatment at the referral dermatology service of the authors' institution. SECONDARY OBJECTIVE: determine signalment, body condition score (BCS), stool quality and comorbidities associated with AS. ANIMALS: Thirty-three dogs with AS presented to the referral dermatology service between 1 January 2010 and 31 March 2021. MATERIALS AND METHODS: An electronic medical record search was conducted. Information regarding sex, breed, age at disease onset, weight, BCS, stool quality, comorbidities, treatment and treatment outcome were collected. Treatment outcome was categorised as "resolved clinically", "clinical signs resolved per owner", "did not complete treatment" or "failed". Dogs were excluded if seen by another service, not treated for AS, or if perianal sinuses (fistulae), anal sac masses, or anal sac abscesses were identified. RESULTS: Nineteen dogs were male and 14 female. Twenty-four breeds were included. Average age at disease onset was 4.4 years. Average BCS was 5.8 of 9. Stool quality was "poor" in seven of 33 and normal in 23 of 33 cases. Atopic dermatitis was the most common comorbidity (12 of 33). Treatment typically consisted of anal sac flushing with saline followed by infusion using a commercially available steroid/antibiotic/antifungal ointment. Treatment was repeated on average 2.9 times. Resolution of AS was obtained in 24 of 33 cases, clinical signs resolved per owner in four of 33, five of 33 cases did not complete treatment, and no cases failed treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Local treatment with flushing and infusion is effective for treating AS in dogs.

Contexte - Peu d'informations ont été publiées concernant le traitement de la sacculite anale canine (SA). Objectifs - Objectif principal : déterminer les résultats du traitement local de la SA au service de dermatologie des auteurs. Objectif secondaire : déterminer le signalement, le score d'état corporel (BCS), la qualité des selles et les comorbidités associées à la SA. Animaux - Trente-trois chiens SA présentés au service de dermatologie entre le 1er janvier 2010 et le 31 mars 2021. Matériels et méthodes - Une recherche dans le dossier médical électronique a été effectuée. Des informations concernant le sexe, la race, l'âge au début de la maladie, le poids, le BCS, la qualité des selles, les comorbidités, le traitement et les résultats du traitement ont été recueillies. Le résultat du traitement a été classé comme « résolu cliniquement ¼, « signes cliniques résolus par le propriétaire ¼, « n'a pas terminé le traitement ¼ ou « échec ¼. Les chiens ont été exclus s'ils étaient vus par un autre service, non traités pour la SA, ou si des sinus périanaux (fistules), des masses du sac anal ou des abcès du sac anal étaient identifiés. Résultats - Dix-neuf chiens étaient des mâles et 14 des femelles. Vingt-quatre races ont été incluses. L'âge moyen au début de la maladie était de 4,4 ans. Le BCS moyen était de 5,8 sur 9. La qualité des selles était « mauvaise ¼ dans sept cas sur 33 et normale dans 23 cas sur 33. La dermatite atopique était la comorbidité la plus fréquente (12 sur 33). Le traitement consistait généralement en un rinçage du sac anal avec une solution saline suivi d'une perfusion à l'aide d'une pommade stéroïde/antibiotique/antifongique disponible dans le commerce. Le traitement a été répété en moyenne 2,9 fois. La résolution de la SA a été obtenue dans 24 des 33 cas, les signes cliniques ont disparu dans quatre des 33 cas, cinq des 33 cas n'ont pas terminé le traitement et aucun cas n'a échoué au traitement. Conclusions et pertinence clinique - Le traitement local par rinçage et perfusion est efficace pour traiter la SA chez le chien.

Introducción- se ha publicado poca información sobre el tratamiento de la saculitis anal canina (AS). Objetivos - Objetivo primario: determinar los resultados del tratamiento local de la AS en el servicio de referencia dermatológica de la institución de los autores. Objetivo secundario: determinar la presentación clínica, la puntuación de la condición corporal (BCS), la calidad de las heces y las comorbilidades asociadas a la AS. Animales - Treinta y tres perros con AS presentados al servicio de dermatología de referencia entre el 1 de enero de 2010 y el 31 de marzo de 2021. Materiales y métodos - Se realizó una búsqueda en la historia clínica electrónica. Se recopiló información sobre sexo, raza, edad de inicio de la enfermedad, peso, BCS, calidad de las heces, comorbilidades, tratamiento y resultado del tratamiento. El resultado del tratamiento se clasificó como "resuelto clínicamente", "signos clínicos resueltos por propietario", "no completó el tratamiento" o "fracasó". Los perros fueron excluidos si fueron vistos por otro servicio, no tratados por AS, o si se identificaron senos perianales (fístulas), masas en los sacos anales o abscesos en los sacos anales. Resultados- diecinueve perros eran machos y 14 hembras. Se incluyeron veinticuatro razas. La edad promedio de inicio de la enfermedad fue de 4,4 años. BCS promedio fue 5.8 de 9. La calidad de las heces fue "mala" en siete de 33 y normal en 23 de 33 casos. La dermatitis atópica fue la comorbilidad más común (12 de 33). El tratamiento generalmente consistía en enjuagar el saco anal con solución salina seguido de una infusión usando un ungüento de esteroide/antibiótico/antifúngico disponible en el mercado. El tratamiento se repitió un promedio de 2,9 veces. La resolución de AS se obtuvo en 24 de 33 casos, los signos clínicos se resolvieron por propietario en cuatro de 33, cinco de 33 casos no completaron el tratamiento y ningún caso fracasó en el tratamiento. Conclusiones y relevancia clínica- el tratamiento local con lavado e infusión intrasacular es eficaz para tratar la AS en perros.

Contexto - Poucas informações foram publicadas sobre o tratamento da saculite anal (SA) canina. Objetivos - Objetivo primário: determinar os desfechos do tratamento tópico localizado da SA em um serviço especializado de dermatologia veterinária da instituição do autor. Objetivo secundário: determinar as manifestações clínicas, escore de condição corporal (ECC), qualidade das fezes e comorbidades associadas à SA. Animais - Trinta e três cães com SA apresentados ao serviço de dermatologia entre 1° de janeiro de 2010 e 39 de março de 2021. Materiais e métodos - Realizou-se um levantamento de prontuários eletrônicos. Foram coletadas informações sobre sexo, raça, idade no surgimento da doença, peso, ECC, qualidade das fezes, comorbidades, tratamentos e desfecho do tratamento. O desfecho do tratamento foi categorizado como "resolvido clinicamente", "sinais clínicos resolvidos de acordo com o tutor", "não completou o tratamento" ou "falhou". Os cães foram excluídos do estudo se tivessem sido tratados em outro serviço, não tivessem sido tratados para SA, ou se fossem identificados abscessos, massas ou fístulas nos sacos anais. Resultados - Dezenove cães eram machos e 14 fêmeas. Vinte e quatro raças foram incluídas. A idade média no surgimento da doença foi de 4,4 anos. O ECC médio foi 5,8 em 9. A qualidade das fezes foi ruim em sete de 33 cães e normal em 22 de 33 casos. A dermatite atópica foi a comorbidade mais comum (12 de 33). O tratamento tipicamente consistiu de lavagem dos sacos anais com solução salina seguido de infusão de uma solução comercial contendo esteroide/antibiótico/antifúngico. O tratamento foi repetido em média 2,9 vezes. Resolução da SA foi alcançada em 24 de 33 casos, os sinais clínicos se resolveram de acordo com o tutor em quatro de 33 casos, cinco de 33 casos não completaram o tratamento e em nenhum caso houve falha terapêutica. Conclusões e relevância clínica - Tratamento tópico com lavagem e infusão é eficaz para tratar SA em cães.

Pathology in Practice.

In collaboration with the American College of Veterinary Pathologists.

Hostage to history - questioning the duration of systemic antimicrobial therapy for the treatment of canine superficial bacterial folliculitis.

Current guidelines for the use of systemic antimicrobials for the treatment of superficial bacterial folliculitis in dogs include the recommendation that the disease be treated for a minimum of 3 weeks and for at least 1 week beyond clinical resolution. With increasing antimicrobial resistance being noted for bacteria involved in this condition, as well as the increased use of evidence-based medicine, this dogma needs to be reevaluated.

Validation of the 0-10 verbal numeric scale for assessment of pruritus severity in dogs.

BACKGROUND: The pruritus Visual Analog Scale (pVAS) is currently the only validated tool for assessing canine pruritus. A verbal numeric scale (VNS) offers an alternative if clients are not present or able to complete the pVAS. HYPOTHESIS/OBJECTIVE: To validate the 0-10 VNS and evaluate its interchangeability with the pVAS. ANIMALS: 251 dogs were included in the study. MATERIALS AND METHODS: Dog owners were asked to assess their pet's pruritus level using the pVAS, the 0-10 VNS and the verbal rating categories (mild, moderate, severe) in one or two subsequent visits. To be valid, VNS must satisfy the following: correlate with pVAS (criterion validity); indicate reduction in itch score after an antipruritic intervention (construct validity); and have scores related to the verbal rating categories that are significantly different (content validity). VNS and pVAS interchangeability and the percentage of clients that preferred the VNS and pVAS also were evaluated. RESULTS: The VNS and pVAS correlation for visits 1 and 2 was good (rICC = 0.9) and excellent (rICC = 0.94). The VNS scores were significantly decreased after antipruritic interventions (P < 0.001). The VNS scores associated with the verbal rating scale categories (mild, moderate and severe) were significantly different (P < 0.001). The 95% limits of agreement for the pVAS and VAS were outside the limit of acceptability of ±2 (-2.0, 2.57). Most clients (69%) preferred the pVAS to the VNS. CONCLUSIONS AND CLINICAL RELEVANCE: The VNS is a valid scale to evaluate canine pruritus; however, the VNS and pVAS are not interchangeable.

Patulous Eustachian tube and palatine defect in a Dachshund with chronic unilateral otitis externa and otitis media.

BACKGROUND: Patulous Eustachian tube (pET) is a rare dysfunction of the Eustachian tube described in humans. It is characterized by failure of the ET to close, resulting in unrestricted passage of air, sound and material between the nasopharynx and the middle ear. OBJECTIVE: To report a case of pET associated with otitis in a dog. ANIMAL: A 6-year old-female spayed Dachshund dog. METHODS AND MATERIALS: Otoscopic examination, cytological evaluation, culture and susceptibility, computerized tomography (CT), video-otoscopic flushing and surgery. RESULTS: Left ear otoscopic examination revealed erythema, purulent frothy discharge, ceruminous gland hyperplasia, stenosis and a partial tear of the tympanum. Cytological evaluation from the left external canal showed neutrophils, macrophages, rods and cocci. Aerobic culture showed predominantly multidrug-resistant Pseudomonas aeruginosa. The CT findings of the left ear included chronic changes in the external canal, marked lysis of the tympanic bulla and marked dilation of the ET. During video-otoscope flushing, saline drained through the mouth. Bilateral incomplete hypoplasia of the soft palate was noted. Total ear canal ablation and bulla osteotomy with ET dissection were curative. Histopathological findings were compatible with chronic otitis externa (OE) and media. CONCLUSION AND CLINICAL IMPORTANCE: To the best of the authors' knowledge, this is the first case of pET described in animals. The ET dysfunction and palatine defect were likely the cause of the otitis in this dog. Clinicians should investigate pET in animals with signs of OE characterized by frothy liquid and food fragments in the ear canal in addition to sneezing after drinking water.

Dermal arteritis of the nasal philtrum: a retrospective study of 23 dogs.

BACKGROUND: Dermal arteritis of the nasal philtrum (DANP) is a cutaneous vascular condition that selectively targets large vessels of the nasal philtrum of dogs; little information is published about this disease. OBJECTIVE: The aim of this study was to report the signalment, clinical signs, treatment options and outcome of dogs with DANP, and to propose a rationale for the clinical diagnosis. ANIMALS: Twenty-three dogs from four referral veterinary clinics from January 2002 to July 2018. METHODS AND MATERIALS: Retrospective analysis of medical records of dogs with diagnosis of DANP. RESULTS: The mean age at disease onset was 5.3 years. Nineteen dogs were pure-bred (11 different breeds) and four were mixed breed. Twenty-three dogs had a clinical diagnosis of DANP and three of these had histopathological confirmation. Eight dogs had episodes of profuse arterial bleeding from the lesion, nine had minor bleeding and six no bleeding. Twenty dogs were managed medically with monotherapy or combined therapy of topical tacrolimus, prednisolone, doxycycline and niacinamide, and/or pentoxifylline. Long-term tacrolimus was prescribed for 15 cases, eight of those cases as sole therapy. Treatment was declined for three dogs and four dogs were lost to follow-up. The lesion was satisfactorily controlled in 12 dogs and well-controlled in four dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: The distinctive presentation of DANP substantiates the clinical diagnosis. Medical treatment seems to be effective in controlling DANP and tacrolimus used as sole or adjunctive therapy appears to manage the disease satisfactorily.

Canine Pruritus Visual Analog Scale: how does it capture owners' perception of their pet's itching level?

BACKGROUND: Accurate measurement of pruritus severity is difficult in veterinary medicine. OBJECTIVES: To determine how the changes in Pruritus Visual Analog Scale (PVAS) scores at follow-up visits agree with the owners' perceptions of improvement of their pet's pruritus. ANIMALS: One hundred and ninety two pruritic dogs were included in the prospective study and 196 in the retrospective study. METHODS AND MATERIALS: Owners were randomly assigned into five groups and PVAS scores were recorded during two consecutive visits. Group A: previous scores were shown before completing the PVAS; Group B: PVAS was completed then owners were shown previous scores and asked to repeat the PVAS; Group C: PVAS was completed as reported previously; Group D: PVAS and a 0-10 verbal scale (VS) were completed. Retrospectively, PVAS scores were analysed during at least three consecutive visits. The average percentage and kappa agreements were calculated for all groups. In addition, PVAS and VS scores were compared in Group D. RESULTS: The average percentage and kappa agreements were higher in groups A (96%; 0.81), B [before (80%; 0.54), after (82%; 0.59) previous score] and D (85%; 0.47). Group C (79%; 0.37) had the lowest agreement. PVAS and VS scores were not significantly different (P = 0.56) in Group D. The average percentage and kappa agreements for the retrospective study were 50.8% and 0.25. The highest values (63%; 0.355) were noted at 30-60 day visit intervals. CONCLUSIONS AND CLINICAL IMPORTANCE: Showing owners previous scores could improve how PVAS captures the owner's perception of their dog's itching level.

Comparison of demographic data, disease severity and response to treatment, between dogs with atopic dermatitis and atopic-like dermatitis: a retrospective study.

BACKGROUND: Limited information is available describing the features of canine atopic-like dermatitis (ALD) compared with atopic dermatitis (AD). OBJECTIVES: To compare demographic data, disease severity and response to therapy between ALD and AD dogs. ANIMALS: Two hundred and fifty-three atopic dogs with intradermal and serum allergen-specific IgE test results were selected retrospectively. METHODS AND MATERIALS: Dogs were enrolled into the ALD group if both IgE tests were negative and into the AD group if at least one test was positive. Demographic data, pruritus level and number of body sites affected before and during therapy, in addition to maintenance therapy protocols, were compared between groups. RESULTS: There were 216 (85.38%) dogs in the AD group and 37 (14.62%) in the ALD group. The soft-coated wheaten terrier, American Staffordshire terrier, English bulldog and Labrador retriever were over-represented in the AD group. No significant differences between the groups were noted regarding the other demographic variables evaluated. There were no differences in the mean pruritus scores and number of affected body sites at the first visit or during treatment. Furthermore, no significant differences between the groups were noted for the maintenance treatment scores and reduction of pruritus level and number of body sites affected during treatment. CONCLUSIONS AND CLINICAL SIGNIFICANCE: The soft-coated wheaten terrier, American Staffordshire terrier, English bulldog and Labrador retriever were over-represented in the AD group. No significant differences in the other demographic data and clinical features were noted between dogs with ALD and AD in the present study.

Probable cutaneous adverse drug reaction to piroxicam in a cat.

CASE SUMMARY: A 9-year-old male neutered Devon Rex cat presented with bilaterally symmetrical ulcerative lesions with mucopurulent exudate that developed rapidly. The lesions were apparent on the axillae, ventral abdomen and inguinal areas. The cat was systemically well. Piroxicam was being administered for palliative treatment of a previously diagnosed salivary adenocarcinoma. Histopathology revealed severe extensive epidermal ulceration with focal dyskeratotic keratinocytes in the stratum granulosum without lymphocyte satellitosis. Resolution of skin lesions was observed after discontinuing piroxicam. Similar lesions developed after previous piroxicam administration, further suggesting a possible adverse reaction to this drug. In addition, the Naranjo score indicated that piroxicam was a probable cause for the ulcerative skin lesions. RELEVANCE AND NOVEL INFORMATION: This is the first report of piroxicam, a non-steroidal anti-inflammatory drug, as a probable cause of ulcerative skin lesions in a cat.

Subcutaneous administration of ciclosporin in 11 allergic cats - a pilot open-label uncontrolled clinical trial.

BACKGROUND: Oral ciclosporin has been reported to be efficacious for feline inflammatory skin diseases; however, cats are often difficult to medicate orally. HYPOTHESIS/OBJECTIVE: To evaluate the efficacy and tolerability of subcutaneous ciclosporin administered to cats with allergic skin disease. ANIMALS: Eleven client-owned cats with nonseasonal clinical signs. METHODS: Prospective open label trial. Ciclosporin 50 mg/mL solution for injection (Sandimune®, Novartis; NJ, USA) was administered subcutaneously for 60 days with initial doses ranging from 2.5 mg/kg once daily (one cat) to every other day (five cats) and 5 mg/kg once daily (four cats) to every other day (one cat). Dosages were adjusted monthly if needed based on clinical response. Clinical response was assessed using a modified FeDESI (feline Dermatitis Extent and Severity Index) and PVAS (pruritus Visual Analog Scale) between days (D) 0, 30 and 60. RESULTS: Six cats completed the study and four of five cats withdrawn from the study were included in an intention-to-treat analysis. There was significant decrease in FeDESI and PVAS scores between D0 and D30, D0 and D60 and D30 and D60 (P < 0.05) in all ten cats. CONCLUSIONS AND CLINICAL IMPORTANCE: Ciclosporin administered subcutaneously at initial doses of 2.5-5 mg/kg, once daily to alternate days, appears to be an efficacious therapy for feline allergic dermatitis and may be an alternative therapy for cats that cannot be treated orally. Randomized and controlled long term studies which include a larger number of cats are needed to confirm these findings.

Can immunosuppressive therapy facilitate the diagnosis and affect the clinical signs of canine scabies? A retrospective study of 79 cases.

BACKGROUND: Scabies infestation is one of the most pruritic dermatoses of dogs. It is often misdiagnosed and dogs are treated with immunomodulatory drugs (IMD) to relieve pruritus. HYPOTHESIS/OBJECTIVES: The primary goals of this study were to determine the impact of IMD on skin scraping results, pruritus level and extent of skin lesions, and to evaluate whether disease duration is associated with positive skin scrapings and contagion. ANIMALS: Seventy nine dogs with a final diagnosis of scabies. METHODS: Inclusion in this retrospective study required a positive skin scraping for scabies or a clinical response to an acaricidal treatment trial. RESULTS: The average pruritus score of dogs that received IMD (8.71) was significantly higher than those that did not (7.43; P = 0.03). However, there were no significant differences in either the rates of positive skin scrapings (79.6% versus 59.1%; P = 0.13) or the mean number of body sites affected (3.8 versus 3.4; P = 0.30) between dogs that received IMD and those that did not. Neither skin scraping status nor duration of clinical signs were correlated with a report of contagion within the household. CONCLUSION/CLINICAL IMPORTANCE: IMD was associated with a significant increase in the pruritus level, but not with the mean number of lesional body sites. Dogs exposed to IMD had a 20.5% higher rate of positive skin scrapings. This difference could be clinically relevant and lack of statistical significance may indicate an underpowered study.

Papillomavirus-associated diseases.

This article reviews various aspects of 3 clinical disorders associated with papillomavirus in horses commonly known as classical viral papillomatosis, genital papillomas/papillomatosis, and aural plaques. Classical papillomatosis is usually asymptomatic and spontaneously resolves within 1 to 9 months; therefore, treatment is often not required. Genital papillomas/papillomatosis have not been reported to spontaneously resolve, and there is increasing evidence that genital papillomas may evolve to in situ or invasive squamous cell carcinomas. Horses with aural plaques may be asymptomatic or may present with signs of ear and head hypersensitivity.

Gene transcription abnormalities in canine atopic dermatitis and related human eosinophilic allergic diseases.

Canine atopic dermatitis (AD) is clinically similar to human AD, implicating it as a useful model of human eosinophilic allergic disease. To identify cutaneous gene transcription changes in relatively early inflammation of canine AD, microarrays were used to monitor transcription in normal skin (n=13) and in acute lesional AD (ALAD) and nearby visibly nonlesional AD (NLAD) skin (n=13) from dogs. Scanning the putative abnormally transcribed genes, several potentially relevant genes, some abnormally transcribed in both NLAD and ALAD (e.g. IL6, NFAM1, MSRA, and SYK), were observed. Comparison for abnormally transcribed genes common to two related human diseases, human AD and asthmatic chronic rhinosinusitis with nasal polyps (aCRSwNP), further identified genes or gene sets likely relevant to eosinophilic allergic inflammation. These included: (1) genes associated with alternatively activated monocyte-derived cells, including members of the monocyte chemotactic protein (MCP) gene cluster, (2) members of the IL1 family gene cluster, (3) eosinophil-associated seven transmembrane receptor EMR1 and EMR3 genes, (4) interferon-inducible genes, and (5) keratin genes associated with hair and nail formation. Overall, numerous abnormally transcribed genes were observed only in canine AD; however, many others are common to related human eosinophilic allergic diseases and represent therapeutic targets testable in dogs with AD.

Frequency of urinary tract infection in dogs with inflammatory skin disorders treated with ciclosporin alone or in combination with glucocorticoid therapy: a retrospective study.

BACKGROUND: Few studies have investigated the frequency of urinary tract infection (UTI) in dogs receiving long-term ciclosporin therapy. HYPOTHESIS/OBJECTIVES: The goal of the study was to investigate the frequency of UTI in dogs receiving ciclosporin with or without glucocorticoids. A secondary goal was to determine whether bacteriuria, pyuria and urine specific gravity were good predictors of UTI, and if ciclosporin dose, concurrent ketoconazole therapy, sex or duration of therapy affected the frequency of UTI. Animals - Eighty-seven dogs with various inflammatory skin disorders and 59 control dogs with inflammatory skin conditions that had not received glucocorticoids or ciclosporin for 6 months were enrolled. METHODS: This study was retrospective. The first urine culture from dogs receiving ciclosporin was compared with control dogs using Fisher's exact test. A logistic mixed model was used to test for association between a positive bacterial culture and duration of treatment, dose of ciclosporin, concurrent ketoconazole therapy and sex. The sensitivities and specificities for bacteriuria, pyuria and urine specific gravity were determined. RESULTS: Twenty-six of 87 (30%) ciclosporin-treated dogs had at least one positive culture. Compared with 3% positive control samples, 15% were positive in treated dogs (P=0.027). The sensitivity and specificity were, respectively, 64.1 and 98.1% for bacteriuria, 74.4 and 70.9% for pyuria, and 56.4 and 65.3% for urine specific gravity. All other analysed parameters were not significantly different. CONCLUSIONS AND CLINICAL IMPORTANCE: The results suggest that routine urine cultures and assessment of bacteriuria by cystocentesis should be part of the monitoring for dogs on long-term ciclosporin with and without glucocorticoids.

The efficacy of imiquimod 5% cream (Aldara® in the treatment of aural plaque in horses: a pilot open-label clinical trial.

Aural plaques affect at least 22% of horses and can be asymptomatic or cause ear sensitivity. Immunohistochemical and electron microscopy studies have shown a strong association between aural plaques and papilloma virus. The purpose of this study was to investigate the efficacy of imiquimod 5% cream, an immune response modifier with potent antiviral activity, in the treatment of equine aural plaques. Twenty-one horses were enrolled and 16 completed the study. Imiquimod 5% cream was applied three times a week, every other week. When both ears were affected only the worst affected ear was treated. Adverse effects in all horses included marked local inflammation, exudation and thick crust formation at the site of treatment and the adjacent skin. Removal of the crust before treatment was painful and required sedation in most horses. Complete resolution of lesions was noted in all horses immediately post-treatment and the long-term resolution rate was 87.5%. Duration of therapy ranged from 1.5 to 8 months (median: 2.9 mean: 3.5). All horses were followed-up for 12-22 months after treatment was discontinued and only two horses had a recurrence of lesions. Clinical signs related to the aural plaques prior to treatment were reported in 11 of 16 (68.8%) horses and included resistance to touching the ears and bridling. Complete resolution of these signs was reported by the owners in all of the horses followed-up for at least 12 months. In conclusion, the topical application of imiquimod 5% cream is an efficacious treatment for aural plaques in horses.

Investigation of the pruritogenic effects of histamine, serotonin, tryptase, substance P and interleukin-2 in healthy dogs.

There are numerous studies of the pruritus-producing effects of histamine, serotonin, tryptase, substance P and interleukin-2 in humans and mice, but very little reported in dogs even though a common reason dogs are presented to veterinarians is pruritus. The aim of this study was to determine whether substances known to cause pruritus in humans also cause pruritus in dogs. Twenty-five clinically healthy research beagle dogs were included in the study. All dogs first received an intradermal injection of 0.05 mL saline as a control substance and were video-recorded for 20 min before and after the injection. Twenty-four hours later the dogs were randomly divided into five groups of five dogs each and randomly assigned to receive histamine, serotonin, tryptase, substance P or interleukin-2 injected intradermally each at the volume of 0.05 mL. On subsequent days, increasing concentrations of each substance were used. Before (baseline) and after the injection of each concentration of the substances, the dogs were video-recorded for 20 min. The frequency and character of pruritus episodes (scratching, licking, chewing, rubbing or rolling) were noted and these data were used for statistical analysis. The number of pruritus episodes was compared among baseline, saline and the different concentrations of each substance. The results showed that dogs did not have a significant increase in pruritic behaviour above baseline or saline after injection of any of the investigated substances (generalized linear model; P = 0.23).