Total lipid concentration of hairs increases after successful attenuation of extrahepatic portosystemic shunts in dogs.

BACKGROUND: Skin and coat quality can reflect nutritional deficiencies in humans and dogs with liver diseases. HYPOTHESIS/OBJECTIVES: Determine skin and coat quality based on a scoring protocol and skin biopsies in dogs with an extrahepatic portosystemic shunt (EHPSS), and determine total lipid concentrations in hairs of dogs at time of surgery and 3 months after successful shunt closure. ANIMALS: Ten client-owned dogs that underwent successful gradual attenuation of EHPSS, as defined by transsplenic portal scintigraphy, were included. MATERIALS AND METHODS: A prospective cohort study was performed. All dogs underwent gradual attenuation of the EHPSS. Skin and coat scoring was performed at diagnosis, surgery, and 1 and 3 months postoperatively. Hair was plucked from the lumbar region for total lipid analysis and an 8 mm punch skin biopsy was taken at time of surgery and 3 months postoperatively, when the dogs underwent transsplenic portal scintigraphy to determine EHPSS closure. RESULTS: No significant differences were observed in skin and coat scoring over time. Total lipid concentrations of hairs increased significantly from surgery to 3 months postoperatively [30 µg/mg hair (13-56 µg/mg hair) to 47 µg/mg hair (25-63 µg/mg hair); p = 0.005]. Skin biopsies showed the presence of significantly more scales 3 months postoperatively (p = 0.018). CONCLUSIONS AND CLINICAL RELEVANCE: A significant increase in total lipid concentrations in hairs suggests that successful surgical attenuation of EHPSS improves either intestinal absorption of lipids, fat metabolism in the liver, or a combination of both.

Contexte - La qualité de la peau et du pelage peut refléter des carences nutritionnelles chez les humains et les chiens atteints de maladies du foie. Hypothèse/Objectifs - Déterminer la qualité de la peau et du pelage sur la base d'un protocole de notation et de biopsies cutanées chez les chiens avec un shunt portosystémique extrahépatique (EHPSS), et déterminer les concentrations totales de lipides dans les poils des chiens au moment de la chirurgie et trois mois après la fermeture réussie du shunt. Animaux - Dix chiens appartenant à des clients qui ont subi une atténuation progressive réussie de l'EHPSS, telle que définie par la scintigraphie portale trans-splénique, ont été inclus. Matériels et méthodes - Une étude de cohorte prospective a été réalisée. Tous les chiens ont subi une atténuation progressive de l'EHPSS. Une notation de la peau et du pelage a été réalisée au moment du diagnostic, de la chirurgie et un et trois mois après l'opération. Les cheveux ont été prélevés dans la région lombaire pour une analyse des lipides totaux et une biopsie cutanée à l'emporte-pièce de 8 mm a été effectuée au moment de la chirurgie et trois mois après l'opération, lorsque les chiens ont subi une scintigraphie portale trans-splénique pour déterminer la fermeture de l'EHPSS. Résultats - Aucune différence significative n'a été observée dans la notation de la peau et du pelage au fil du temps. Les concentrations totales de lipides dans les poils ont augmenté de manière significative entre la chirurgie et trois mois après l'opération [30 µg/mg de poils (13-56 µg/mg de poils) à 47 µg/mg de poils (25-63 µg/mg de poils) ; P = 0,005]. Les biopsies cutanées ont montré la présence de significativement plus d'écailles trois mois après l'opération (P = 0,018). Conclusions et pertinence clinique - Une augmentation significative des concentrations totales de lipides dans les cheveux suggère qu'une atténuation chirurgicale réussie de l'EHPSS améliore soit l'absorption intestinale des lipides, soit le métabolisme des graisses dans le foie, soit une combinaison des deux.

Introducción- la calidad de la piel y el pelaje puede reflejar deficiencias nutricionales en humanos y perros con enfermedades hepáticas. Hipótesis/Objetivos- determinar la calidad de la piel y el pelaje según un protocolo de valoración y en biopsias de piel en perros con shunt portosistémico extrahepática (EHPSS) y determinar las concentraciones totales de lípidos en el pelo de los perros en el momento de la cirugía y tres meses después del tratamiento exitoso del shunt. Animales- se incluyeron diez perros de propietarios particulares que se sometieron a una atenuación gradual exitosa de EHPSS, según se identificó mediante por gammagrafía portal transesplénica. Materiales y métodos - Se realizó un estudio de cohorte prospectivo. A todos los perros se les realizó una atenuación gradual del EHPSS. La valoración de la piel y el pelaje se realizó en el momento del diagnóstico, la cirugía y uno y tres meses después de la operación. Se arrancó el pelo de la región lumbar para el análisis de lípidos totales y se tomó una biopsia de piel con sacabocados (punch) de 8 mm en el momento de la cirugía y tres meses después de la operación, cuando los perros se sometieron a una gammagrafía portal transesplénica para determinar el cierre de EHPSS. Resultados- no se observaron diferencias significativas en la valoración de la piel y el pelaje a lo largo del tiempo. Las concentraciones de lípidos totales del pelo aumentó significativamente desde la cirugía hasta los tres meses posteriores a la operación [30 µg/mg de pelo (13-56 µg/mg de pelo) a 47 µg/mg de cabello (25-63 µg/mg de pelo); P = 0,005]. Las biopsias de piel mostraron la presencia de mayor cantidad de escamas de forma significativa tres meses después de la operación (P = 0,018). Conclusiones y relevancia clínica- un aumento significativo en las concentraciones de lípidos totales en el pelo sugiere que la atenuación quirúrgica exitosa de EHPSS mejora la absorción intestinal de lípidos, el metabolismo de las grasas en el hígado o una combinación de ambos.

Contexto - A qualidade da pele e dos pelos pode refletir deficiências nutricionais em humanos e cães com hepatopatias. Hipótese/Objetivos - Determinar a qualidade da pele e pelos baseada em um protocolo de escore e biópsias cutâneas em cães com shunt portossistêmico extra-hepático (EHPSS) e determinar as concentrações lipídicas totais nos pelos de cães no momento da cirurgia e três meses após o fechamento bem-sucedido do shunt. Animais - Foram incluídos dez cães de proprietários submetidos à atenuação gradual do EHPSS bem-sucedida, confirmada por cintilografia portal transesplênica. Materiais e métodos - Realizou-se um estudo de coorte prospectivo. Todos os cães foram submetidos à atenuação gradual do EHPSS. A classificação de pele e pelos em escores foi realizada no diagnóstico, cirurgia, e com um e três meses de pós-operatório. Os pelos foram arrancados da região lombar para análise lipídica total e uma biópsia com punch de 8mm foi coletada no momento da cirurgia e com três meses de pós-operatório, quando os cães foram submetidos à cintilografia portal transesplênica para determinar o fechamento do EHPSS. Resultados - Não foram observadas diferenças significativas nos escores de pele e pelos ao longo do tempo. As concentrações de lipídicas totais aumentaram significativamente da cirurgia aos três meses de pós-operatório [30 µg/mg de pelo (13-56 µg/mg pelo) para 47 µg/mg de pelo (25-63 µg/mg de pelo); P = 0,005]. As biópsias cutâneas revelaram a presença de significativamente mais escamas com três meses de pós-operatório (P = 0,018). Conclusões e relevância clínica - O aumento significativo de concentrações lipídicas totais nos pelos sugere que a atenuação cirúrgica de EHPSS bem-sucedida melhora tanto a absorção intestinal de lipídeos quanto o metabolismo de gordura no fígado, ou uma combinação dos dois.

Persistent hypercobalaminemia three months after successful gradual attenuation of extrahepatic shunts in dogs: a prospective cohort study.

BACKGROUND: Deficiencies in vitamin A and D and disorders in the vitamin B complex are often present in people with chronic liver diseases. So far, the serum concentrations of these vitamins have not yet been studied in dogs with congenital extrahepatic portosystemic shunts (EHPSS), who also have some degree of liver dysfunction. The objective was to assess serum vitamin concentrations in dogs with EHPSS from diagnosis to complete closure. A prospective cohort study was performed using ten client-owned dogs with EHPSS, closed after gradual surgical attenuation. Serum concentrations of vitamin A, 25-hydroxyvitamin D, folic acid, cobalamin and methylmalonic acid (MMA) were measured at diagnosis prior to institution of medical therapy, prior to surgery, and three months after gradual attenuation and complete closure of the EHPSS. RESULTS: At diagnosis, median serum concentrations of vitamin A, 25-hydroxyvitamin D and folic acid were 18.2 µg/dL (8.8 - 79.5 µg/dL), 51.8 ng/mL (19.4 - 109.0 ng/mL), and 8.1 µg/L (5.2 - 14.5 µg/L), respectively, which increased significantly postoperatively (88.3 µg/dL (51.6 - 182.2 µg/dL, P=0.005), 89.6 ng/mL (49.3 - >150.0 ng/mL, P =0.005), and 14.8 µg/L (11.5 - 17.7 µg/L, P <0.001), respectively). Median serum cobalamin concentrations were 735.5 ng/L (470 - 1388 ng/L) at diagnosis and did not significantly decrease postoperatively (P =0.122). Both at diagnosis and three months postoperatively 7/10 dogs had hypercobalaminemia. CONCLUSIONS: Serum concentrations of vitamin A, 25-hydroxyvitamin D and folic acid significantly increase after surgical attenuation. Nevertheless, persistent hypercobalaminemia is suggestive of ongoing liver dysfunction, despite successful surgery.

Pilot study of dogs with suppurative and non-suppurative Malassezia otitis: A case series.

BACKGROUND: Rarely, Malassezia otitis presents as a painful, erosive otitis with an otic discharge containing Malassezia and neutrophils on cytology. There are no published reports of this type of suppurative Malassezia otitis (SMO). The role of Malassezia hypersensitivity in otitis is still unknown, and no association has been demonstrated with SMO. We compared Malassezia IgE levels, intradermal test and histology changes in SMO dogs with the more conventional Malassezia otitis (MO) presentation. RESULTS: Three dogs (case 1, case 2 and case 3) were diagnosed with SMO, one dog (case 4) was diagnosed with unilateral MO and unilateral SMO, and one dog (case 5) was diagnosed with MO. Only one case (case 4) with SMO/MO had a positive Intradermal Allergy Test (IDAT) and elevated IgE levels for Malassezia. Histopathology findings from SMO revealed: interface dermatitis (case 1 and 3), lymphocytic dermatitis (case 2) and chronic hyperplastic eosinophilic and lymphoplasmacytic dermatitis (case 4). Histopathology findings from MO showed perivascular dermatitis (case 4 and 5). All the cases were treated successfully. CONCLUSIONS: SMO presents with a distinct clinical phenotype in comparison with conventional MO. No consistent aetiology could be isolated. In these clinical cases it is possible that previous treatments could have influenced the results. More research is needed to understand the possible aetiologies and the pathogenesis of SMO.

Plasma amino acid profiles in dogs with closed extrahepatic portosystemic shunts are only partially improved 3 months after successful gradual attenuation.

BACKGROUND: Dogs with portosystemic shunts have an altered blood amino acid profile, with an abnormal branched-chained amino acid (BCAA)-to-aromatic amino acid (AAA) ratio being the most common abnormality. Different liver diseases have distinctive amino acid profiles. OBJECTIVES: Determine the changes in plasma amino acid profiles in dogs with extrahepatic portosystemic shunts (EHPSS) from diagnosis to complete closure. ANIMALS: Ten client-owned dogs with EHPSS closed after surgical attenuation. METHODS: Prospective cohort study. Medical treatment was instituted in dogs diagnosed with EHPSS. At least 4 weeks later, gradual surgical attenuation was performed. Three months postoperatively, EHPSS closure was confirmed by transsplenic portal scintigraphy. Clinical signs were scored and blood was taken before institution of medical treatment, at time of surgery, and 3 months postoperatively. At the end of the study, the plasma amino acid profiles were analyzed in batch. RESULTS: The median BCAA-to-AAA ratio was extremely low (0.6) at time of diagnosis and remained low (0.5) at time of surgery, despite the fact that median neurological score significantly improved from 22 to 2 after starting medical treatment (P = .04). Three months after surgical attenuation, a significantly higher BCAA-to-AAA ratio (1.5) was observed (P < .001). CONCLUSIONS AND CLINICAL IMPORTANCE: Medical treatment does not improve the BCAA-to-AAA ratio in dogs with EHPSS, despite substantial clinical improvement. Although the ratio significantly increased after EHPSS closure, it was still indicative of moderate to severe hepatic dysfunction in all dogs.

Detection of allergen-specific antibody-secreting cells in dogs by ELISPOT.

Current laboratory tests are unable to distinguish healthy from allergic dogs. Unlike serum antibody responses, circulating antibody-secreting cells (ASC) are temporarily induced after each contact with the antigen. These ASC can be identified using ELISPOT and the observation of allergen-specific ASC might correlate with the causative allergens in dogs with an allergic dermatitis. In this study, blood was sampled from six privately-owned allergic dogs and six non-allergic laboratory beagles to determine the frequency of circulating allergen-specific ASC for common allergens. Blood IgE+, IgA + and IgG + cells were magnetically isolated to determine the number of allergen-specific ASC with ELISPOT for Dermatophagoides farinae, Dermatophagoides pteronyssinus, Alternaria alternata, birch, timothy grass, wheat, cow's milk, bovine, chicken and lamb meat. For IgA and IgG, allergen-specific spots were observed, however for IgE, no spots were detected for any of the allergens. ELISPOT could not differentiate allergic from non-allergic dogs. When the responses to the different allergens were compared, more IgA ASC for D. pteronyssinus were observed compared to some of the other allergens which was statistically significant for the non-allergic dogs and approached significance in the allergic dogs. These findings indicate that ELISPOT can be used to identify circulating allergen-specific IgA- and IgG-secreting cells. The technique did however not detect allergen-specific IgE ASC and was unable to distinguish allergic from non-allergic dogs. Only a small number of studies have studied allergen-specific IgA in dogs. The finding that dogs have higher numbers of D. pteronyssinus-specific IgA ASC points out that apart from IgE and IgG, it might be interesting to include IgA measurements for certain allergens to analyse the complete spectrum of both the protective and pro-allergic antibody responses.

Feline cutaneous nodular and ocular Cryptococcus neoformans in Belgium.

CASE SUMMARY: An 11-year-old spayed female cat presented with a 6-month history of a progressive nodular skin disease with concurrent, ocular lesions, intermittent vomiting, halitosis and weight loss. The cat had received different topical treatments without success prior to referral to the Dermatology Department of Faculty of Veterinary Medicine, Ghent University. Several fine-needle aspirations of the lesions showed a vast number of macrophages with intra-cytoplasmic inclusions compatible with Cryptococcus species. Histopathological examination revealed pyogranulomatous inflammation with capsulated yeast. Periodic acid-Schiff stain was positive. Latex cryptococcal antigen agglutination test on serum was positive with a titre of >1/524,288. PCR and fungal culture identified Cryptococcus neoformans. The cat was treated with itraconazole 10 mg/kg PO q24h. After 10 months of therapy, there was a complete resolution of the lesions except for a small nodule on the ventral aspect of the tongue. RELEVANCE AND NOVEL INFORMATION: As far as we are aware, this is the first feline case reported of cutaneous nodular cryptococcosis without nasal involvement in Belgium. Oral itraconazole therapy was well tolerated and appeared to give a good result and prognosis.

Skin disease in donkeys (Equus asinus): a retrospective study from four veterinary schools.

BACKGROUND: Donkeys are important throughout the world as work animals and occasionally as pets or a meat source. Most descriptions of skin disease in donkeys are reported in small case series, textbooks or review articles. HYPOTHESIS/OBJECTIVES: To document skin diseases and their prevalence in donkeys and to investigate predilections for the most common conditions. ANIMALS: Case populations at four veterinary schools totalling 156 donkeys. METHODS AND MATERIALS: A retrospective study was performed by searching computerized medical records, using the key word "donkey", at the School of Veterinary Medicine, University of California, Davis (UCD). Records of donkeys from the veterinary schools in Nantes, France; Utrecht, Netherlands and Ghent, Belgium were searched in a similar manner. The time periods included in the searches varied by institution. RESULTS: At UCD, 83 of 346 (24%) of donkeys had skin disease noted in their records. The most common diagnoses were insect bite hypersensitivity, sarcoid and habronemiasis. At Nantes, 36 of 144 (25%) had skin disease and the most common diagnoses were sarcoid and superficial pyoderma. At Utrecht 23 of 143 (16%) had skin disease and the most common diagnosis was dermatophytosis. At Ghent, 14 of 320 (4%) had skin disease and the most common diagnosis was sarcoid. CONCLUSIONS AND CLINICAL IMPORTANCE: Cutaneous conditions in donkeys are common. Age, sex and breed predisposition and the most common diagnoses varied with geographical location. Clinicians should include a dermatological examination regardless of the reason for presentation.

Biomechanical properties of celiotomy wounds closed with tape and cyanoacrylate versus intradermal sutures.

OBJECTIVE: To compare cutaneous wound closure with mesh and 2-octyl cyanoacrylate (MOC) vs an intradermal suture pattern (ISP) in terms of time of application and biomechanical properties. SAMPLE POPULATION: Experimental study with 12 female beagle dogs. METHODS: A skin incision was created from the xiphoid to the pubis as part of an ovariohysterectomy; the linea alba and subcutaneous tissue were closed routinely. Half of the skin incision was closed with MOC, and the other half was closed with an ISP. Tissue samples were collected from both sections at days 14 and 28 and tested for ultimate strength and stiffness. RESULTS: Closure with MOC (72.8 ± 14.0 s) was faster than with an ISP (398.4 ± 36.4 s; P = .001). The ultimate load and stiffness increased with time for MOC (P = .005 and P = .005, respectively) and ISP (P < .001 and P < .001, respectively). On day 14, ultimate load and stiffness were greater in wounds closed with MOC compared with ISP (P = .014 and P = .02, respectively). No difference between groups was detected at day 28. CONCLUSION: Cutaneous wound closure with MOC was faster and resulted in superior strength at 14 days compared with closure with an ISP in this healthy population. CLINICAL SIGNIFICANCE: Mesh and 2-octyl cyanoacrylate offers an attractive alternative to ISP for skin closure after celiotomy in dogs, especially if surgical/anesthesia time is a concern.

First evidence of Besnoitia bennetti infection (Protozoa: Apicomplexa) in donkeys (Equus asinus) in Belgium.

BACKGROUND: Besnoitiosis is caused by different species of intracellular protozoan parasites belonging to the family Sarcocystidae and affecting multiple host species worldwide. Including B. besnoiti, ten species are described infecting animals. Among ungulates, Besnoitia bennetti infects horses, donkeys and zebras and was described in Africa and in the USA where donkey besnoitiosis is considered as an emerging disease. CASE PRESENTATION: A two-year-old male donkey was purchased in May 2016 in poor body condition (cachexia, alopetic areas and pruritus mainly on neck and head) by the present owner in Le Roeulx (Belgium) from a milk producing donkey farm in Frasnes-lez-Buissenal (Belgium). Shortly after its purchase and shearing, the donkey presented with crusts, hyperkeratosis (both flanks and neck) anorexia and cachexia. A treatment with phoxim was given with no improvement. A cutaneous biopsy of hyperkeratotic skin was performed in July. It showed a perivascular eosinophilic infiltrate with a large thick walled cyst located in the dermis containing numerous bradyzoites. This was highly suggestive of besnoitiosis. Several skin biopsy samples were obtained for qPCR analysis and confirmed the presence of Besnoitia spp. DNA. Further laboratory diagnosis tests were performed (western blot and rDNA sequencing) confirming Besnoitia bennetti aetiology for the male. For the female, the punch-biopsy, haematology and qPCR were negatives but the western blot showed the presence of antibodies directed to Besnoitia spp. Further clinical examination performed in August highlighted scleral pinhead sized cysts (pearl) in the right eye and between nares. Another ten-year-old female donkey purchased in France and sharing the same accommodation showed a good clinical condition, but a thorough clinical examination showed the presence of numerous cysts on the inner face of upper labial mucosa. A daily treatment based on sulfamethaxzole and trimethoprim (Emdotrim 60% Mix®, 30 mg/kg) was given orally and some improvement was noticed. CONCLUSION: This is the first evidence of Besnoitia bennetti infection (Protozoa: Apicomplexa) in donkeys (Equus asinus) in Belgium.

Prevalence of external ear disorders in Belgian stray cats.

Objectives Feline otitis externa is a multifactorial dermatological disorder about which very little is known. The objective of this study was to map the prevalence of external ear canal disorders and the pathogens causing otitis externa in stray cats roaming around the region of Ghent, Belgium. Methods One hundred and thirty stray cats were randomly selected during a local trap-neuter-return programme. All cats were European Shorthairs. This study included clinical, otoscopic and cytological evaluation of both external ears of each cat. Prospective data used as parameters in this study included the sex, age and body condition score of each cat, as well as the presence of nasal and/or ocular discharge, and the results of feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV) Snap tests. Results Remarkably, very few (sub)clinical problems of the external ear canal were found in the stray cat population. Malassezia species was by far the most common organism found in the external ear canals of the 130 stray cats. A total of 96/130 (74%) cats were found to have Malassezia species organisms present in one or both ears based on the cytological examination. No correlation was found between the parameters of sex, age, body condition score, the presence of nasal and/or ocular discharge and FIV and FeLV status, and the presence of parasites, bacteria or yeasts. Conclusions and relevance This study provides more information about the normal state of the external ear canal of stray cats. The ears of most stray cats are relatively healthy. The presence of Malassezia species organisms in the external ear canal is not rare among stray cats.

Morphological variability of Demodex cati in a feline immunodeficiency virus-positive cat.

CASE DESCRIPTION A 17-year-old FIV-positive cat was evaluated because of weight loss during the preceding few months. The cat had a weight loss of 0.5 kg (1.1 lb) during the last month. Because of its FIV-positive status, the cat was confined indoors. CLINICAL FINDINGS A large nonpruritic area of alopecia with hyperpigmentation and comedones was present on the right lateral aspect of the neck. The chin had diffuse alopecia and comedones. Mild alopecia was present on the dorsal aspect of the muzzle. Trichography and microscopic examination of acetate tape imprint preparations and skin scrapings revealed a very morphologically heterogeneous population of Demodex mites. Micrometry of adult mites revealed a broad range of body lengths (92.68 to 245.94 µm), which suggested that as many as 3 Demodex spp might be present in the skin lesions of this cat. TREATMENT AND OUTCOME Owing to its concurrent disease, no treatment was initiated for the demodicosis, and the cat died spontaneously 14 days after the evaluation. Sequence analysis of the 16S rRNA gene of collected mites was performed. Analysis revealed that the 16S rRNA gene sequence of collected mites appeared 100% identical to the Demodex cati 16S rRNA gene sequence deposited in GenBank (JX193759). A similarity of 79.2% and 74.4% was found when the 16S rRNA gene sequence of collected mites was compared with that of Demodex gatoi (JX981921) and Demodex felis (KF052995), respectively. CLINICAL RELEVANCE Demodicosis in cats is often associated with underlying disease. In cats, FIV infection may lead to an altered immune response and induce species polymorphism of Demodex mites.

Cutaneous adverse drug reaction in a dog associated with imepitoin.

BACKGROUND: The macroscopic appearance of cutaneous adverse drug reactions can be similar to a plethora of skin diseases and in particular may resemble autoimmune and immune-mediated disorders. The reaction can occur after single or multiple administrations, with the latter varying in durations of up to years of treatment. These reactions are mostly self-limiting with cessation of the offending drug. OBJECTIVES: To report a cutaneous adverse drug reaction associated with chronic administration of imepitoin. CASE REPORT: A 4-year-old, Jack Russell terrier dog was presented with progressive skin lesions of 1-week duration. The dog had a 6 month history of idiopathic epilepsy treated with imepitoin for the previous 5 months. Imepitoin is an anti-epileptic drug that acts as a low-affinity partial agonist of the benzodiazepine site at the GABAA receptor. The dosage of imepitoin was increased from 20 mg/kg twice daily to 30 mg/kg twice daily, 3 days before the onset of skin lesions, due to uncontrolled seizures. [Correction added on 15 February 2016 after first online publication: In the preceding sentence, the dosage of imepitoin was previously incorrect and has been amended in this current version.] Dermatological examination revealed erythema and exfoliation at the mucocutaneous junctions of the lips, lip folds, philtrum, ears, axillae and the ventral abdomen. Small erosions and depigmentation were visible on the oral mucosa, lip folds and philtrum. Histopathology was supportive of a lupoid drug reaction. Complete resolution of skin lesions was seen after discontinuation of imepitoin and low dose of prednisolone during a period of 4 weeks. No recrudescence of skin lesions was observed during a 6 month follow-up period. CONCLUSION AND CLINICAL IMPORTANCE: Imepitoin may result in cutaneous adverse drug reactions in dogs.

Study of the behaviour of lesional and nonlesional skin of canine recurrent flank alopecia transplanted to athymic nude mice.

BACKGROUND: Recurrent flank alopecia is a clinically well-described skin disorder in dogs. The pathomechanism of the disease is difficult to study because it undergoes spontaneous regression. HYPOTHESIS/OBJECTIVES: To study the behaviour of xenografts in mice in order to assess the feasibility of a reproducible experimental model and to investigate local or systemic causes of canine recurrent flank alopecia (cRFA). METHODS: Skin biopsies were taken from lesional and nonlesional skin of two client-owned dogs with cRFA and grafted onto five athymic mice from a research facility. The lesional skin and xenografted skin were evaluated histologically on day 0 and day 30, respectively. RESULTS: Transplanted lesional and nonlesional canine skin regrew hair within 30 days, while the donor dogs were still alopecic in the lesional areas on day 30 after the skin biopsy procedure. Graft rejection was evidenced histologically in two xenografted athymic mice. Lesional hyperpigmentation disappeared in the athymic mice. CONCLUSIONS AND CLINICAL IMPORTANCE: This study showed that hair follicles from dogs with cRFA quickly regenerated and regrew hair once grafted onto the mice. Our data indicate that the pathogenesis of cRFA is likely to be mediated by systemic rather than local factors. While this xenograft approach might not be of much value for the study of cRFA, it has potential value for the study of other causes of canine alopecia due to systemic factors.

Idiopathic sterile inflammation of the epidural fat and epaxial muscles causing paraplegia in a mixed-breed dog.

CASE DESCRIPTION: A 4-year-old sexually intact male mixed-breed dog was evaluated because of clinical signs of acute-onset pelvic limb ataxia, rapidly progressing to paraplegia with severe spinal hyperesthesia. CLINICAL FINDINGS: General physical examination revealed pyrexia, tachycardia, and tachypnea. Neurologic examination demonstrated severe spinal hyperesthesia and paraplegia with decreased nociception. Magnetic resonance imaging revealed extradural spinal cord compression at T13-L1 and hyperintense lesions on T1- and T2-weighted images in the epaxial musculature and epidural space. TREATMENT AND OUTCOME: Decompressive surgery, consisting of a continuous dorsal laminectomy, with copious lavage of the vertebral canal was performed. Cultures of blood, urine, and surgical site samples were negative. Histologic examination results for samples obtained during surgery demonstrated suppurative myositis and steatitis. These findings confirmed a diagnosis of sterile idiopathic inflammation of the epidural fat and epaxial muscles with spinal cord compression. The dog's neurologic status started to improve 1 week after surgery. After surgery, the dog received supportive care including antimicrobials and NSAIDs. The dog was ambulatory 1 month after surgery and was fully ambulatory despite signs of mild bilateral pelvic limb ataxia 3 years after surgery. CLINICAL RELEVANCE: Although idiopathic sterile inflammation of adipose tissue, referred to as panniculitis, more commonly affects subcutaneous tissue, its presence in the vertebral canal is rare. Specific MRI findings described in this report may help in reaching a presumptive diagnosis of this neurologic disorder. A definitive diagnosis and successful long-term outcome in affected patients can be achieved by decompressive surgery and histologic examination of surgical biopsy samples.

Immunohistochemical localization of fibroblast growth factor 18 in hair follicles of healthy beagle dogs.

Increasing emphasis is being placed on the role of fibroblast growth factors (FGFs) in hair follicle cycling. In mice, expression of FGF18 mRNA peaks during the late telogen phase, leading to the hypothesis that FGF plays a role in anagen induction. There are no data on the presence of FGF18 in dogs. The main objective of this study was to identify and locate FGF18 in the canine hair follicle. The second objective was to assess potential differences in FGF18 concentration between biopsies taken in winter and summer, shoulder and flank regions, and between different sexes. Skin tissue from 10 healthy beagle dogs (three intact females, three spayed females and four intact males) was collected from the shoulder and flank. The biopsies were collected in February and August on day 0, after which the dogs were clipped and biopsies collected again from the shoulder and flank on days 1, 3, 7 and 17. Paraffin sections (4 µm thick) of the biopsies were stained with an anti-FGF18 antibody. The FGF18-positive cells were counted in the hair follicle epithelium from seven follicular units of each biopsy. Fibroblast growth factor 18 was detected as granular cytoplasmatic staining in follicles at the level of the inner root sheath, and rarely in the outer root sheath and dermal papilla. It was also detected in the apocrine glands, in arrector pili muscles and in vascular endothelial cells. There was no statistical difference in the number of FGF18-positive cells or follicles between sexes, different anatomical locations, seasons or the consecutive days of sampling.

Organic diseases mimicking acral lick dermatitis in six dogs.

Acral lick dermatitis ("lick granuloma") in dogs is often thought to have a behavioral etiology. However, other diseases may cause lesions on the distal legs, mimicking acral lick dermatitis. In this report, six dogs were presented with acral lick dermatitis-like lesions from different underlying causes-namely lymphoma, an orthopedic pin, deep pyoderma, mast cell tumor, leishmaniasis, and (presumptive) sporotrichosis.

Use of hyposensitization injections to control seasonal pruritus in a Bactrian camel (Camelus bactrianus).

A 9-yr-old, female Bactrian camel (Camelus bactrianus) developed severe pruritus in June 1993. During the next 8 yr, the camel exhibited annual episodes of pruritus and epiphora, generally beginning in June and subsiding in October of each year. These signs could usually be controlled with topical agents and fly repellents, although pruritus flare-ups were effectively controlled with intermittent injections of diphenhydramine and corticosteroids. There were no signs during the colder months. The pruritus became more severe and difficult to control when the camel reached its 18th year. Histopathologic descriptions of skin biopsies taken from several sites suggested a hypersensitivity reaction with secondary changes because of bacterial infection or corticosteroid administration (or both). An intradermal test (IDT) performed using 62 allergens regionalized to Northern California resulted in 17 positive test sites. Hyposensitization therapy was initiated using allergens chosen on the basis of exposure, availability, and the results of the IDT, using standard protocols. The clinical signs of pruritus were markedly reduced in the 2 yr after the hyposensitization injections were initiated.