Laura Buckley

Comparative in vitro efficacy of antimicrobial shampoos: a pilot study

This study compared the antimicrobial efficacy of shampoos against meticillin-sensitive Staphylococcus pseudintermedius (MSSP), meticillin-resistant S. pseudintermedius (MRSP), antibiotic-sensitive Pseudomonas aeruginosa (PA), multidrug-resistant P. aeruginosa (MDR-PA) and Malassezia pachydermatis. Three isolates were incubated for 10, 30 and 60 min with each shampoo diluted in phosphate-buffered saline. Aliquots were then incubated for 16-18 h on sheep blood agar (bacteria) or for 3 days on Sabourauds dextrose agar (Malassezia). The minimal bactericidal concentrations (MBCs) for chlorhexidine products (Malaseb(®), Pyoderm(®)/Microbex(®) and Hibiscrub(®)) were 1:1,024-1:2,048 for MSSP and MRSP, 1:512-1:1,024 for PA and MDR-PA, and 1:2,048-1:5,096 for Malassezia at all time points. The MBCs for benzoyl peroxide (Paxcutol(®)) for MSSP and MRSP were 1:2-1:8 at 10 min, and 1:256 after 30 and 60 min. A 1:2 dilution was effective against Pseudomonas, and 1:512-1:1,024 dilutions were effective against Malassezia at all time points. The MBCs for ethyl lactate (Etiderm(®)) for MSSP and MRSP were 1:2 at 10 min, and 1:2-1:16 after 30 and 60 min. A 1:2 dilution was effective against Pseudomonas, and a 1:512 dilution was effective against Malassezia at all time points. Chloroxylenol (Coatex(®)) and acetic acid-boric acid (Malacetic(®)) were not effective against MSSP, MRSP or Pseudomonas. Both were effective against Malassezia at 1:8-1:16 dilution at 10 min, and at 1:8-1:32 dilution after 30 and 60 min. In conclusion, chlorhexidine appeared to be the most effective topical biocide, and MRSP and MDR-PA were no less susceptible than antibiotic-sensitive organisms. These results should, however, be confirmed with larger numbers of isolates.

Efficacy of a 0.0584% hydrocortisone aceponate spray in presumed feline allergic dermatitis: an open label pilot study

This study evaluated the efficacy of a 0.0584% hydrocortisone aceponate (HCA) spray (Cortavance(®); Virbac SA) in 10 cats with presumed allergic dermatitis. The cats initially received two sprays/100 cm(2) of skin once daily. Clinical lesions (a Feline Dermatitis Extent and Severity Index; FeDESI), pruritus (10 cm visual analog scale with grade descriptors) and owner assessments of efficacy, tolerance and ease of use (from 1=very poor to 5=excellent) were assessed every 14 days. The frequency of treatment was reduced after day 28 in cats with a >50% reduction in FeDESI and pruritus scores. One cat was lost to follow up at day 28 and two at day 42. Intention-to-treat data were analysed. The FeDESI [mean (SD): day 0, 42.2 (15.7) and day 56, 9.9 (11.7); P<0.0001] and pruritus scores [day 0, 61.2 mm (20.1) and day 56, 14.6 mm (16.1); P<0.0001] significantly decreased throughout the trial. The owner scores for tolerance [median (range): day 14, 4 (1-5) and day 56, 4 (3-5); P=0.003] and ease of administration [day 14, 3 (2-5) and day 56, 4 (2-5); P=0.02] significantly increased during the trial, but there was no significant change in efficacy scores [day 14, 4 (3-5) and day 56, 4 (2-5); P=0.5]. There were no adverse effects attributable to the HCA spray, no significant changes in weight [mean (SD): day 0, 5.0 kg (1.4) and day 56, 5.0 kg (1.6); P=0.51] and no significant changes in haematology, biochemistry or urinalysis (n=4). Six cats required every-other-day treatment and four required daily treatment. In conclusion, HCA spray appeared to be effective and safe in these cats, although it is not licensed for use in this species.

Feline Eosinophilic Granuloma Complex(ITIES): Some clinical clarification

Practical relevance: The feline eosinophilic granuloma complex (EGC) comprises a group of clinically well recognised but poorly understood dermatoses that are common in cats. In many cases, lesions are severe and can be accompanied by varying degrees of (and sometimes considerable) pruritus and/or pain. In addition, lesions can be chronic and recurrent. It is, therefore, important to achieve a prompt and accurate diagnosis in order to provide optimal, often life-long, treatment for affected cats. Patient group: There is no age predisposition or well documented breed predilection for the development of EGC lesions in cats. Some studies have reported a possible female predisposition, but this has not been consistently documented. Clinical challenges: The clinical diagnosis of EGC lesions is usually straightforward, but investigation of the potential underlying aetiology can pose a challenge for the clinician. Information on the indication for various diagnostic tests and their interpretation is lacking, and the tendency for these cases to be managed with chronic medical intervention prior to achieving a definitive diagnosis can further complicate the interpretation of any diagnostic investigation. In addition, successful therapeutic management of these cases can be challenging. Some cats suffer only a single episode of disease that resolves with treatment, while others have recurrent lesions and some of these can be refractory to treatment. The individual variation in both the clinical nature of the disease and the response to therapy could be related to disease severity, but could also be explained by differences in the underlying aetiopathogenesis. Evidence base: This article reviews the published literature to discuss the complex aetiology of the EGC and present an overview of the different clinical presentations and diagnosis. A further and particular aim has been to provide some evidence-based recommendations for the management of this unusual group of dermatoses.

Cross-reaction and co-sensitization among related and unrelated allergens in canine intradermal tests

BACKGROUND Intradermal tests are used to identify allergens for avoidance and immunotherapy in atopic dogs. HYPOTHESIS/OBJECTIVES To evaluate cross-reaction or co-sensitization among 53 intradermal test allergens. ANIMALS Six hundred and fifty-one client-owned dogs with atopic dermatitis. METHODS Intradermal tests were performed with 53 house dust/storage mite, epidermal, insect, tree, weed and grass pollen and mould allergens. Pairwise comparisons were used to calculate the odds ratios (ORs), 95% confidence intervals (CIs) and statistical significance for the results of each allergen pair, with significance at P < 0.0006 (Holm-Bonferroni correction to reduce the false-detection rate). RESULTS Apart from cotton, cockroach, red clover, grain smut and Penicillium, the results for the allergens within each group were statistically associated [ORs from 4.7 (CI 2.5-8.9) to 1229.4 (CI 166.5-1795.1); P = 0.0005 to P < 0.0001]. Excluding red clover and cotton, 94% of results between tree, weed and grass pollens were also statistically associated [ORs from 8.3 (CI 3.6-24.7) to 117 (CI 29.1-341); P = 0.0005 to P < 0.0001]. In contrast, few allergens from unrelated groups were statistically associated [ORs from 0.12 (CI 0.03-1.1) to 27.7 (CI 0.2-93); P = 1.0 to P < 0.0001]. The mean (SD) of the log e transformed ORs for the related and statistically associated allergens [5.3 (1.3)] was significantly greater than those for related but nonstatistically associated [1.7 (1.6)] or unrelated allergens [1.4 (1.4); P < 0.0001]. CONCLUSIONS AND CLINICAL IMPORTANCE This suggests that there is cross-reaction or co-sensitization between related allergens. This could have implications for allergen selection in testing and immunotherapy, but further studies are required to differentiate cross-reaction from co-sensitization.

A pilot study comparing in vitro efficacy of topical preparations against veterinary pathogens.

BACKGROUND Topical antimicrobial agents are important for the management of cutaneous infections. For topical antimicrobial agents, in vitro efficacy data are limited. OBJECTIVES To determine and compare the minimum bactericidal/fungicidal concentrations (MBCs/MFCs) of several topical antimicrobial agents against veterinary pathogens. MATERIALS AND METHODS Two chlorhexidine, two oxychlorine based products (NaOCl & HOCl) lime sulfur (LS), manuka honey (MH) and hydrocortisone aceponate (HCA) were tested against American Type Culture Collection (ATCC) and clinical isolates: meticillin susceptible and resistant Staphylococcus pseudintermedius (MSSP), qac A/B carrying MSSP, antimicrobial susceptible and extended spectrum beta-lactamase producing Escherichia coli, multidrug-resistant Pseudomonas aeruginosa and Malassezia pachydermatis. The MBCs/MFCs were measured, where available, using a broth microdilution method; isolates were incubated for 3 and 10 min. RESULTS Chlorhexidine and isopropyl alcohol (Chl(1) ) showed significantly lower MBCs (0.46 mg/L -937.50 mg/L, P = 0.027) compared to chlorhexidine and climbazole (Chl², 58.59 mg/L-1875 mg/L). NaOCl and HOCl showed excellent antimicrobial activity with HOCl having significantly lower MBCs compared to NaOCl (0.03 mg/L-1.72 mg/L and 0.03 mg/L-1.95 mg/L, respectively, P = 0.042). The detectable MBCs for LS and HCA were high, being close to the starting concentration (5,000 mg/L and 146 mg/L, respectively). The MBC/MFC for MH was not detectable. Amongst all test products there was no significant effect of contact time or isolate resistance status. CONCLUSIONS AND CLINICAL IMPORTANCE Chlorhexidine, NaOCl and HOCl demonstrated low MBCs against tested organisms, suggesting potential in vivo efficacy. The selection of an appropriate antimicrobial agent, however, cannot be based exclusively upon MBC/MFC data; other factors should be considered.

Presentation, clinical pathological and post mortem findings in three related Scottish terriers with ligneous membranitis

Ligneous conjunctivitis and gingivitis were diagnosed in three related Scottish terrier dogs presented for investigation of severe conjunctivitis and respiratory signs. Hypoplasminogenaemia was confirmed in one of the three affected dogs. Supportive treatment was not effective, and the dogs died or were euthanased because of the disease. Post-mortem analysis of two of the dogs revealed multiple abnormalities including severe proliferative fibrinous lesions affecting the conjunctiva, gingiva, trachea, larynx and epicardium and multiple fibrous adhesions throughout the thoracic and abdominal cavities. One dog had internal hydrocephalus and lacked a cerebellar vermis. Ligneous membranitis was confirmed on histopathology. This is a rare condition in dogs but an important differential diagnosis for severe conjunctivitis and gingivitis.

Successful multimodal treatment of Paecilomyces lilacinus infection in a dog

A four-year-old English springer spaniel was presented with a nine-month history of immune-mediated thrombocytopenia and one-month history of ulcerative skin lesions. Histopathology of the skin lesions identified intralesional fungal yeasts and hyphae. Definitive diagnosis was achieved via culture, which identified the organism as Paecilomyces lilacinus. This report describes the successful management of the first UK documented case of canine P lilacinus infection following tapering of immunosuppressive treatment and combined antifungal therapy.

Treatment of presumed allergic skin disease in cats

Feline dermatology presents a number of challenges when it comes to diagnosing individual diseases, due to the more subtle and varied nature of skin lesions in cats compared to those commonly seen in dogs. In feline allergic skin disease (FASD), the diagnostic challenge is increased further as cats present with one or more of four patterns of disease, rather than the more typical character and distribution of lesions seen in canine hypersensitivity dermatitis cases. Cats are also generally more solitary animals and secretive in their behaviour, which can lead to the absence of important clues in the clinical history. There can also be challenges in both the administration of treatment and the comparatively poor treatment responses seen in some patients. This article reviews the important steps that should be taken to diagnose and successfully manage FASD, with particular reference to head and neck excoriations or pruritus, which can be among the more challenging presentations to treat.

Efficacy of a 0.0584% hydrocortisone aceponate spray in presumed feline allergic dermatitis: an open label pilot study: Hydrocortisone aceponate in cats

This study evaluated the efficacy of a 0.0584% hydrocortisone aceponate (HCA) spray (Cortavance(®); Virbac SA) in 10 cats with presumed allergic dermatitis. The cats initially received two sprays/100 cm(2) of skin once daily. Clinical lesions (a Feline Dermatitis Extent and Severity Index; FeDESI), pruritus (10 cm visual analog scale with grade descriptors) and owner assessments of efficacy, tolerance and ease of use (from 1=very poor to 5=excellent) were assessed every 14 days. The frequency of treatment was reduced after day 28 in cats with a >50% reduction in FeDESI and pruritus scores. One cat was lost to follow up at day 28 and two at day 42. Intention-to-treat data were analysed. The FeDESI [mean (SD): day 0, 42.2 (15.7) and day 56, 9.9 (11.7); P<0.0001] and pruritus scores [day 0, 61.2 mm (20.1) and day 56, 14.6 mm (16.1); P<0.0001] significantly decreased throughout the trial. The owner scores for tolerance [median (range): day 14, 4 (1-5) and day 56, 4 (3-5); P=0.003] and ease of administration [day 14, 3 (2-5) and day 56, 4 (2-5); P=0.02] significantly increased during the trial, but there was no significant change in efficacy scores [day 14, 4 (3-5) and day 56, 4 (2-5); P=0.5]. There were no adverse effects attributable to the HCA spray, no significant changes in weight [mean (SD): day 0, 5.0 kg (1.4) and day 56, 5.0 kg (1.6); P=0.51] and no significant changes in haematology, biochemistry or urinalysis (n=4). Six cats required every-other-day treatment and four required daily treatment. In conclusion, HCA spray appeared to be effective and safe in these cats, although it is not licensed for use in this species.

Efficacy of a 0.0584% hydrocortisone aceponate spray in presumed feline allergic dermatitis

This study evaluated the efficacy of a 0.0584% hydrocortisone aceponate (HCA) spray (Cortavance(®); Virbac SA) in 10 cats with presumed allergic dermatitis. The cats initially received two sprays/100 cm(2) of skin once daily. Clinical lesions (a Feline Dermatitis Extent and Severity Index; FeDESI), pruritus (10 cm visual analog scale with grade descriptors) and owner assessments of efficacy, tolerance and ease of use (from 1=very poor to 5=excellent) were assessed every 14 days. The frequency of treatment was reduced after day 28 in cats with a >50% reduction in FeDESI and pruritus scores. One cat was lost to follow up at day 28 and two at day 42. Intention-to-treat data were analysed. The FeDESI [mean (SD): day 0, 42.2 (15.7) and day 56, 9.9 (11.7); P<0.0001] and pruritus scores [day 0, 61.2 mm (20.1) and day 56, 14.6 mm (16.1); P<0.0001] significantly decreased throughout the trial. The owner scores for tolerance [median (range): day 14, 4 (1-5) and day 56, 4 (3-5); P=0.003] and ease of administration [day 14, 3 (2-5) and day 56, 4 (2-5); P=0.02] significantly increased during the trial, but there was no significant change in efficacy scores [day 14, 4 (3-5) and day 56, 4 (2-5); P=0.5]. There were no adverse effects attributable to the HCA spray, no significant changes in weight [mean (SD): day 0, 5.0 kg (1.4) and day 56, 5.0 kg (1.6); P=0.51] and no significant changes in haematology, biochemistry or urinalysis (n=4). Six cats required every-other-day treatment and four required daily treatment. In conclusion, HCA spray appeared to be effective and safe in these cats, although it is not licensed for use in this species.