Conducting a dietary trial to diagnose food allergy in dogs and cats
Hilary Jackson and Veronique Dembele, Dermatology Referral Service, Glasgow
Confirming a diagnosis of a food allergy relies on performing a dietary trial with the subsequent re-emergence of clinical signs upon exposure to the food allergen involved. However, selecting an appropriate trial diet may be complicated, and consideration must be given to the financial impact on the clients and the diet’s acceptability to the pet. The authors describe an approach to conducting a food trial aimed at maintaining owner compliance and assuring the accuracy of the findings. The trial should focus on using a single protein source the pet has not previously encountered, with a hydrolysed product as the preferred choice. They highlight the potential sources of allergens that may undermine the trial, such as treats, flavoured toothpaste, human food and the subject stealing rations from other pets in the household. The authors warn that in order to achieve a success rate of around 95 percent, the pet should be kept on a strict elimination diet for up to eight weeks.
Veterinary Dermatology [Early view]
Emergence of an exotic parasite affecting the skin of equids in Ireland
Stacy Tinkler and others, The Donkey Sanctuary Ireland, Mallow, County Cork
Besnoitiosis is a disease of wild and domestic animals caused by a cyst-forming coccidial parasite, Besnoitia,that is closely related to Toxoplasma gondii and Neosporum spp. A species found exclusively in equids, Besnoitia bennetti, has been identified in various European countries, including the UK. The authors describe the clinical features of two cases involving donkeys born and raised on the same premises in southwest Ireland. One was a 30-month-old jenny presented for the removal of a suspected sarcoid, and the second was a two-year-old gelding with signs of dermatitis around the muzzle area. Diagnosis of besnoitiosis was based on histopathology findings and confirmed by polymerase chain reaction (PCR). Both cases were unresponsive to treatment with trimethoprim sulfadiazine.
Irish Veterinary Journal, 77, 2
Laboratory findings in a case of keloidal fibroma in a dog
Jelena Palić and others, IDEXX Laboratories, Kornwestheim, Germany
Keloids appear at sites of cutaneous injury and result from an abnormal wound healing process in genetically susceptible individuals. They occur commonly in humans and are occasionally seen in dogs but have not been described in other species. The authors describe the case of a five-year-old English Bulldog that presented with a firm, well-circumscribed 1cm-diameter mass on its left flank. The lesion was surgically removed and submitted for cytological, histopathological and immunohistochemical analysis. The authors describe the laboratory findings from the sample, which contained spindle cells, numerous bundles of thick glassy eosinophilic material (hyalinised collagen) and inflammatory cells. They note that in such cases histopathological examination is necessary to distinguish between keloidal fibroma and keloidal fibrosarcoma.
Veterinary Clinical Pathology, 52, 676-680
Cervicofacial cellulitis in six pyrexic rabbits
Chelsey Tournade and others, University of Wisconsin-Madison
Cellulitis involves deep dermal and subcutaneous inflammation, usually resulting from a bacterial infection. Cellulitis affecting the cervicofacial region has previously been reported in rabbits, but the condition has not been well characterised. The authors describe the findings in six cases examined at a university clinic. Each rabbit presented with anorexia or hyporexia and all were pyrexic with a rectal temperature above 40.2°C. Physical examination and computed tomography revealed soft tissue swelling but no evidence of periodontal disease. A bacterial culture of aspirated fluid revealed a range of different organisms. In all six cases, the patient died or was euthanised, including two rabbits that initially responded to systemic antibiotics.
Journal of Small Animal Practice, 65, 66-74
Potential medical treatment for equine malignant melanoma
Paula Zscherpe and others, University of Zurich, Switzerland
Grey horses are particularly prone to developing malignant melanoma, which can be difficult to treat surgically if located on certain parts of the body. There is, therefore, a need for a safe and effective medical treatment for these tumours. Betulinic acid and its synthetic derivative NVX-207 have been shown to have cytotoxic properties against melanoma cells in other species. The authors describe a trial of these agents in an in vitro model of equine skin. They compared the cell permeability of the agents delivered with either a novel oxygen flow-assisted (OFA) transdermal application device or a microemulsion gel. Each formulation was shown to reach the required inhibitory concentrations for these agents, and the OFA method demonstrated a significant accumulation effect. Further in vivo studies using the OFA method are recommended.
BMC Veterinary Research, 20, 202
Surgical treatment of hair growth on the tongue of a Labrador Retriever
Eliot Gougeon and others, CHV Frégis, Paris, France
Median lingual hair heterotopia is a rare phenomenon in canine patients in which hair follicles and shafts develop on the median plane of the tongue. The authors describe a case in a nine-year-old male Labrador Retriever. The dog presented with dysphagia, halitosis, buccal swelling and drooling associated with ulcerative lesions and hairs on the tongue. There was no response to antibiotic treatment, but the hairs were successfully eliminated with a carbon dioxide laser. Histopathological examination of biopsy samples revealed a pyogranulomatous inflammation centred on the growing hairs. On re-examination 10 months later, the glossitis and all clinical signs had disappeared despite the partial recurrence of hair growth on the dorsal sulcus and in the sublingual fistula.
Canadian Veterinary Journal, 65, 213-219
Correlation between local weather conditions, pollen counts and pruritus in dogs
Laura Widorn and others, Ludwig-Maximilian University, Munich, Germany
Canine atopic dermatitis occurs due to an interaction of genetic and environmental factors, potentially including airborne allergens such as pollen. There have been no previous attempts to identify associations between the weather conditions that affect pollen concentrations and clinical signs in dogs with chronic skin disease. The authors carried out a prospective study comparing owner-assessed clinical signs in 37 dogs with confirmed atopic dermatitis and local weather conditions. Humidity and medication levels were shown to correlate with pruritus scores, but there was no link between specific pollen counts and the pruritus scores in dogs with positive intradermal testing scores for those allergens. The findings highlight the importance of careful interpretation of IDT results and question the value of airborne pollen capture systems in monitoring exposure to specific allergens.
Veterinary Dermatology [Early view]
Cutaneous Serratia marcescens infection in two dogs
Jinho Park and Ji-Seon Yoon, Jeonbuk National University, Iksan, South Korea
Serratia marcescens is a Gram-negative bacillus of the Enterobacteriaceae family, a saprophytic water organism widely distributed in the environment. It is known to cause opportunistic infections in critically ill or immunocompromised patients and may also cause cutaneous infections involving cellulitis, hidradenitis and necrotising fasciitis. There have been few previous reports of infections in dogs. The authors describe two cases in two male dogs: one involved multiple ulcerations on the dorsal trunk, and the other had ulceration and a purulent discharge on the nasal bridge. Treatment with topical chlorhexidine and oral antibiotics resulted in the resolution of clinical signs within two weeks, and there was no recurrence of the infection.
Journal of Small Animal Practice, 65, 270-273
