Dilated pore of Winer in a dog.

A 9-year-old male neutered Goldendoodle was presented to the Animal Medical Center of Seattle with a history of a firm, hairless, cystic mass on the dorsal aspect of the neck. The mass had been present for 2 years and would periodically rupture and discharge moderate quantities of yellow-green, soft, semi-solid, keratinaceous material. As rupture of the mass was reported to cause the patient significant pain and discomfort, it was surgically excised. Histopathology of the mass revealed a bulbous keratin-filled cyst that communicated with the external environment via a small ostium. At the base of the cyst, the cyst lining was characterized by a markedly irregular and hyperplastic stratified squamous epithelium with an overt stratum granulosum and prominent, irregularly sized, shaped and spaced rete ridges. At the superficial aspect of the cyst near the ostium, the cystic lining was characterized by a relatively thinner stratified squamous epithelium with an overt stratum granulosum and regular basal contour. Based on the histomorphological appearance of the mass, a diagnosis of a dilated pore of Winer was made. Dilated pores of Winer are follicular cysts arising from the infundibulum of the hair follicle. They are relatively common in humans and uncommon in cats, and single case reports have been described in a horse and a woodchuck (Marmota monax). To the best of the authors' knowledge, this is the first description of a dilated pore of Winer in a dog.

Granulomatous mural folliculitis in 16 domestic goats: Infection with malignant catarrhal fever viruses and colocalization with ovine herpesvirus-2 using in situ hybridization.

Granulomatous mural folliculitis (GMF) is an uncommon reaction pattern occasionally observed in nonadapted ruminant hosts infected with malignant catarrhal fever viruses. This report characterizes GMF and concurrent cutaneous lesions in 16 goats with crusting dermatitis using histochemistry including hematoxylin and eosin, periodic acid-Schiff, and Grocott's methenamine silver, and immunohistochemistry for CD3, CD20, ionized calcium binding adaptor molecule 1, and cytokeratin AE1/3. Infiltrates in all 16 GMF cases consisted of macrophages and fewer T lymphocytes, and variably included eosinophils, multinucleated histiocytic giant cells, and/or neutrophils. Formalin-fixed paraffin-embedded skin and fresh skin samples from caprine GMF cases were tested using pan-herpesvirus nested conventional polymerase chain reaction (PCR) and partial sequencing, ovine herpesvirus-2 (OvHV-2) real-time PCR, and OvHV-2 colorimetric in situ hybridization (ISH). Five of 16 goats with GMF (31%) were PCR positive for malignant catarrhal fever viruses, including caprine herpesvirus 3 in 1 goat and OvHV-2 in 4 goats. Three goats also had positive intranuclear OvHV-2 hybridization signal in follicular keratinocytes, among other cell types, localized to areas of GMF. Herpesviruses were not detected in the formalin-fixed paraffin-embedded skin of 9 goats without GMF. This case series describes relatively frequent detections of malignant catarrhal fever viruses in the skin of goats with GMF, including the first report of caprine herpesvirus 3, and localizes OvHV-2 infected follicular keratinocytes within areas of GMF.

Widespread, symmetric, noninflammatory alopecia associated with follicular dysplasia in the American red squirrel (Tamiasciurus hudsonicus).

This report describes a unique pattern of alopecia in 8 American red squirrels (Tamiasciurus hudsonicus) from 2013 to 2021. All animals were juveniles; 6 were female and 2 were male. Seven presented between September and November, and one presented in April. All squirrels had widespread, bilaterally symmetric, noninflammatory, well-demarcated alopecia involving the entire trunk and legs and normal hair on their muzzle and dorsal surfaces of their paws. Six months later, a normal hair coat had grown on 2 of the animals, which were littermates. Hair fully grew 2 months later in another animal. Histopathology of the alopecic skin was performed in 7 of 8 animals. The following changes were noted: bent and coiled hairs, perforating folliculitis, melanin clumping, and distortion of hair shafts. Based on features of follicular dysplasia and apparent seasonality, this condition has some similarities to canine seasonal flank alopecia. A genetic etiology is suspected.

Histopathologic and molecular characterization of Erethizon dorsatum papillomavirus 1 and Erethizon dorsatum papillomavirus 2 infection in North American porcupines (Erethizon dorsatum).

Erethizon dorsatum papillomavirus 1 (EdPV1) and Erethizon dorsatum papillomavirus 2 (EdPV2) are associated with cutaneous papillomas in North American porcupines (Erethizon dorsatum). This study defined gross, histopathologic, and molecular characteristics of viral papillomas in 10 North American porcupines submitted to the New York State Animal Health Diagnostic Center. Investigation for the presence of EdPV1 and EdPV2 DNA via polymerase chain reaction (PCR) was performed in 9 of the 10 (90.0%) porcupines, and all porcupines were investigated for the detection and localization of EdPV1 and EdPV2 E6 and E7 nucleic acid via chromogenic in situ hybridization (CISH). Next-generation sequencing (NGS) was performed in 2 porcupines. Papillomas were diagnosed on the muzzle (n = 4), caudal dorsum (n = 1), upper lip (n = 1), chin (n = 1), gingiva (n = 2), and nasal planum (n = 1). Histologically, the lesions consisted of hyperplastic epidermis or epithelium with orthokeratotic keratin, prominent keratohyalin granules, and intranuclear inclusion bodies. PCR identified EdPV1 in 6 of 9 samples and EdPV2 in the remaining 3 samples. NGS resulted in 100% genome coverage of EdPV1 and 76.20% genome coverage of EdPV2 compared with GenBank reference sequences, with 99.8% sequence identity to the complete EdPV2 L1 gene of a novel subtype recently identified in France. Hybridization patterns in 9 of the 10 (90.0%) porcupines were characterized by strong nuclear signals in the superficial epidermis, with strong nuclear and punctate cytoplasmic signals in the stratum spinosum and basale. In one animal, CISH suggested dual EdPV1 and EdPV2 infection.

The effect of a mixed cannabidiol and cannabidiolic acid based oil on client-owned dogs with atopic dermatitis.

BACKGROUND: Cannabidiol (CBD) and cannabidiolic acid (CBDA) are reported to have antinociceptive, immunomodulatory and anti-inflammatory actions. OBJECTIVES: To determine if CBD/CBDA is an effective therapy for canine atopic dermatitis (cAD). ANIMALS: Thirty-two privately owned dogs with cAD. MATERIALS AND METHODS: Prospective, randomised, double-blinded, placebo-controlled study. Concurrent therapies were allowed if remained unchanged. Dogs were randomly assigned to receive either 2 mg/kg of an equal mix of CBD/CBDA (n = 17) or placebo for 4 weeks. On Day (D)0, D14 and D28, Canine Atopic Dermatitis Extent and Severity Index, 4th iteration (CADESI-04) and pruritus Visual Analog Scale (pVAS) scores were determined by investigators and owners, respectively. Complete blood count, serum biochemistry profiles and cytokine bioassays were performed on serum collected on D0 and D28. RESULTS: There was no significant difference in CADESI-04 from D0 to D14 (p  = 0.42) or D28 (p  = 0.51) in either group. pVAS scores were significantly lower for the treatment group at D14 (p  = 0.04) and D28 (p  = 0.01) and a significant change in pVAS from baseline was seen at D14 (p  = 0.04) and not D28 (p  = 0.054) between groups. There was no significant difference in serum levels of interleukin (IL)-6, IL-8, monocyte chemoattractant protein - 1, IL-31 or IL-34 between groups at D0 or D28. Elevated alkaline phosphatase was observed in four of 17 treatment group dogs. CONCLUSIONS AND CLINICAL RELEVANCE: CBD/CBDA as an adjunct therapy decreased pruritus, and not skin lesions associated with cAD in dogs.

Contexte - Le cannabidiol (CBD) et l'acide cannabidiolique (CBDA) auraient des actions antinociceptives, immunomodulatrices et anti-inflammatoires. Objectifs - Déterminer si le CBD/CBDA est une thérapie efficace pour la dermatite atopique canine (cAD). Animaux - Trente-deux chiens de propriétaires privés atteints de cAD Matériels et méthodes - Étude prospective, randomisée, en double aveugle, contrôlée versus placebo. Les thérapies concomitantes étaient autorisées si elles restaient inchangées. Les chiens ont été répartis au hasard pour recevoir soit 2 mg/kg d'un mélange égal de CBD/CBDA (n = 17) soit un placebo pendant quatre semaines. Aux jours (J)0, J14 et J28, les scores Canine Atopic Dermatitis Extent and Severity Index, 4th iteration (CADESI-04) et prurit Visual Analog Scale (pVAS) ont été déterminés respectivement par les investigateurs et les propriétaires. Une formule sanguine complète, des profils biochimiques sériques et des dosages biologiques des cytokines ont été réalisés sur le sérum prélevé à J0 et J28. Résultats - Il n'y avait pas de différence significative au CADESI-04 de J0 à J14 (P = 0,42) ou J28 (P = 0,51) dans les deux groupes. Les scores pVAS étaient significativement inférieurs pour le groupe de traitement à J14 (P = 0,04) et J28 (P = 0,01) et un changement significatif de la pVAS par rapport à l'inclusion a été observé à J14 (P = 0,04) et non à J28 (P = 0,054) entre les groupes. Il n'y avait pas de différence significative dans les taux sériques d'interleukine (IL)-6, IL-8, protéine chimiotactique des monocytes-1, IL-31 ou IL-34 entre les groupes à J0 ou J28. Une phosphatase alcaline élevée a été observée chez quatre des 17 chiens du groupe de traitement. Conclusions et pertinence clinique - Le CBD/CBDA en tant que traitement d'appoint a diminué le prurit, et non les lésions cutanées associées à la DAC chez les chiens.

Introducción- se ha descrito que el cannabidiol (CBD) y el ácido cannabidiólico (CBDA) tienen acciones antinociceptivas, inmunomoduladoras y antiinflamatorias. Objetivos- determinar si el CBD/CBDA es una terapia eficaz para la dermatitis atópica canina (CAD). Animales - Treinta y dos perros de propietarios privados con cAD Materiales y métodos - Estudio prospectivo, aleatorio, doble ciego, controlado con placebo. Se permitieron terapias concurrentes si permanecían sin cambios. Los perros fueron asignados al azar para recibir 2 mg/kg de una mezcla igual de CBD/CBDA (n = 17) o placebo durante cuatro semanas. En el día (D)0, D14 y D28, los investigadores y los propietarios determinaron las puntuaciones del índice de extensión y gravedad de la dermatitis atópica canina, cuarta revisión (CADESI-04) y la escala análoga visual de prurito (pVAS), respectivamente. Se realizaron hemogramas completos, perfiles bioquímicos séricos y bioensayos de citoquinas en suero obtenido en D0 y D28. Resultados- no hubo diferencias significativas en CADESI-04 de D0 a D14 (P = 0,42) o D28 (P = 0,51) en ninguno de los grupos. Las puntuaciones de pVAS fueron significativamente más bajas para el grupo de tratamiento en D14 (P = 0.04) y D28 (P = 0.01) y se observó un cambio significativo en pVAS desde el inicio en D14 (P = 0.04) y no en D28 (P = 0.054) entre grupos . No hubo diferencias significativas en los niveles séricos de interleuquina (IL)-6, IL-8, proteína quimioatrayente de monocitos-1, IL-31 o IL-34 entre los grupos en D0 o D28. Se observó fosfatasa alcalina elevada en cuatro de los 17 perros del grupo de tratamiento. Conclusiones y relevancia clínica- CBD/CBDA como terapia adjunta disminuyó el prurito y no las lesiones cutáneas asociadas con la CAD en perros.

Contexto - O canabidiol (CBD) e ácido canabidiólico (CBDA) são relatados como tendo ações antinociceptivas, imunomoduladoras e anti-inflamatórias. Objetivos - Determinar se CBD/CBDA é eficaz no tratamento da dermatite atópica canina (CAD) Animais - Trinta e dois cães de propriedade privada com DAC. Materiais e métodos - Estudo prospectivo, randomizado, duplo-cego, placebo-controle. As terapias concomitantes foram permitidas se permanecessem inalteradas. Os cães foram divididos aleatoriamente em dois grupos, o que receberia 2 mg/kg de uma mistura igual de CBD/CBDA (n = 17) ou placebo durante quatro semanas. No Dia (D) 0, D14 e D28, o Índice de Extensão e Gravidade da Dermatite Atópica Canina, 4ª iteração (CADESI-04) e os escores da Escala Visual Analógica de Prurido (pVAS) foram determinados pelos investigadores e proprietários, respectivamente. Hemograma completo, perfis bioquímicos séricos e ensaios de citocinas foram realizados no soro coletado em D0 e D28. Resultados - Não houve diferença significativa no CADESI-04 de D0 a D14 (P = 0,42) ou D28 (P = 0,51) em nenhum dos grupos. Os escores de pVAS foram significativamente menores para o grupo de tratamento no D14 (P = 0,04) e D28 (P = 0,01) e observou-se uma alteração significativa no pVAS do D0 comparado ao D14 (P = 0,04) e não ao D28 (P = 0,054) entre os grupos. Não houve diferença significativa nos níveis séricos de interleucina (IL)-6, IL-8, proteína quimiotática de monócitos-1, IL-31 ou IL-34 entre os grupos em D0 ou D28. Elevação na fosfatase alcalina foi observada em quatro dos 17 cães do grupo de tratamento. Conclusões e relevância clínica - CBD e CBDA como uma terapia adjuvante é capaz de reduzir prurido, mas não lesões cutâneas associadas à DAC em cães.

Shope fibroma of the eyelid margin in a domestic rabbit.

OBJECTIVE: To describe the clinical and histopathologic features as well as response to treatment of a solitary Shope fibroma affecting the eyelid margin of a domestic rabbit. ANIMAL STUDIED: A seven-year-old female intact domestic rabbit with a progressively enlarging firm, pedunculated, and encrusted inferior eyelid mass of the left eye of 1-month duration. PROCEDURES: Under general anesthesia, the crust was removed revealing an ulcerated mass that was excised via a house-shaped resection and submitted for histopathology. Purulent discharge associated with the mass was swabbed for aerobic and anaerobic bacterial culture and sensitivity testing. Histopathology revealed intraepithelial, cytoplasmic leporipoxviral inclusion bodies consistent with Shope fibroma virus. There was no growth on aerobic or anaerobic bacterial culture. The lesion was completely excised, and no recurrence was noted during a 3-month follow-up period. CONCLUSIONS: The solitary nature and clinical appearance of this eyelid margin Shope fibroma are unique. Shope fibroma should be considered a differential diagnosis for eyelid masses in rabbits even in the absence of other cutaneous masses. Thorough systemic evaluation to attempt to distinguish Shope fibroma from malignant myxomatosis should be performed.

Treatment and outcomes of dogs with hepatocutaneous syndrome or hepatocutaneous-associated hepatopathy.

BACKGROUND: Superficial necrolytic dermatitis (SND) in dogs is a rare disorder most commonly associated with hepatocutaneous syndrome. Although often reported as fatal, sporadically reported long-term remissions might be more common than previously believed and linked to treatment regimens. HYPOTHESIS/OBJECTIVES: Evaluate treatments and associated outcomes in dogs with hepatocutaneous-associated hepatopathy (HCH) with or without SND, designated collectively aminoaciduric canine hypoaminoacidemic hepatopathy syndrome (ACHES). ANIMALS: Forty-one dogs of various breeds and ages diagnosed with ACHES. METHODS: Retrospective study. Electronic surveys, medical records (2014-2019), and communication with veterinarians provided data. Three treatment categories were each dichotomized: IV amino acid (IV-AA) infusions (≥2 vs <2), supplements including S-adenosylmethionine (SAMe), arginine with ornithine, glutathione, lysine, proline, omega-3 fatty acids, or zinc (≥3 vs <3), and diet type (home-cooked vs commercial). Optimal treatment was defined as receiving ≥2 IV-AA treatments, ≥3 nutritional supplements, and a home-cooked diet. RESULTS: Most dogs (29/41, 71%) received IV-AA infusions (23/29, ≥2 infusions). Twenty-one dogs (51%) were fed commercial diets; 17/41 (41%) were fed home-cooked diets. Most dogs received SAMe (32/41, 78%) and a median of 3 supplements. In 4 dogs, HCH remission occurred. Overall all-cause median survival time (MST) was 359 days, and disease-specific MST was 557 days (range, 1-1783 days). Optimally treated dogs (n = 9) lived significantly longer (MST, >1783 days, P = .02) than variably treated dogs (MST, 214 days). CONCLUSIONS AND CLINICAL IMPORTANCE: Optimized ACHES management can resolve SND and HCH and confer long-term survival.

Clinical features and amino acid profiles of dogs with hepatocutaneous syndrome or hepatocutaneous-associated hepatopathy.

BACKGROUND: Superficial necrolytic dermatitis (SND), hepatocutaneous-associated hepatopathy (HCH), aminoaciduria, and hypoaminoacidemia define hepatocutaneous syndrome (HCS) in dogs. Dogs without SND but that possess all other syndrome components are not well described. HYPOTHESIS/OBJECTIVES: To define an inclusive syndrome, aminoaciduric canine hypoaminoacidemic hepatopathy syndrome (ACHES) for dogs with HCH or HCS. Compare clinical features, salient clinicopathologic variables, and plasma and urine amino acid (AA) profiles among ACHES cases by skin lesion status. ANIMALS: Dogs of various breeds and ages diagnosed with ACHES (n = 41). A control (CON) cohort (n = 12) provided AA profile data. METHODS: Retrospective case series. Available medical records of previously identified cases were reviewed for salient clinical features and clinical pathology data. Plasma and urine AA profiles were performed. Cutaneous lesion status was classified as none, mild, or fulminant. RESULTS: Thirty cases (73%) developed SND at some time. Dogs with fulminant skin lesions at diagnosis (n = 22/41, 54%) had significantly lower hematocrit (P = .05) and mean corpuscular volume (P = .01) than dogs without SND. Principal component analysis of plasma AA profiles identified distinct clustering of CON from ACHES dogs, but not by skin lesion status. Plasma 1-methylhistidine (<7 nmol/mL) and cystathionine (<7.5 nmol/mL) were robust ACHES biomarkers. Urine lysine (>344 nmol/mg creatinine) and methionine (>68 nmol/mg creatinine) also were useful ACHES biomarkers. CONCLUSIONS AND CLINICAL IMPORTANCE: Specific AA biomarkers provide additional diagnostic utility in ACHES. Data suggests that HCH is an early stage, and SND a later stage manifestation of ACHES.

Influence of locoregional lymph node aspiration cytology vs sentinel lymph node mapping and biopsy on disease stage assignment in dogs with integumentary mast cell tumors.

OBJECTIVE: To compare the effect of sentinel lymph node (SLN) histology vs locoregional lymph node (LRLN) fine needle aspiration (FNA) cytology on assigned disease stage and adjunctive treatment recommendations and describe the incidence of anatomic disparity between the LRLN and SLN. STUDY DESIGN: A pre-post study refers to a study design type in which subjects are compared pre and post the intervention of interest. ANIMALS: Seventeen dogs undergoing primary excision of 20 cutaneous and subcutaneous mast cell tumors (MCT). METHODS: Client-owned dogs presenting to the Cornell University Hospital for Animals for surgical removal of a cytologically confirmed cutaneous or subcutaneous MCT >1 cm in diameter were enrolled. Cytological examination of FNA from the LRLN was compared with histology of the SLN. The SLN was identified by indirect computed tomographic lymphangiography (ICTL) after peritumoral injection of iopamidol and scanning at 1, 3, 5, 10, and 15 minutes. Histopathologic node score > 1 was considered metastatic. After case review by an oncologist, LRLN FNA cytology was compared with SLN histology for effect on changes in stage assignment and adjunctive treatment recommendations. RESULTS: Mast cell tumors were graded as 2 low (n = 11), 2 high (n = 2), and subcutaneous (n = 7). Optimal scan timing was 10 minutes after injection of iopamidol. Sentinel lymph node differed anatomically from LRLN in 5 of 18 scans. Metastases were detected by histology in 9 of 20 SLN compared with in 1 of 20 FNA of LRLN (P = .001), changing stage and adjunctive treatment recommendations 8 of 20 tumors. Only 6 of 19 LRLN FNA samples were diagnostic. CONCLUSION: Sentinel lymph nodes were consistently identified with ICTL and differed from LRLN in one-quarter of tumors. Histopathological examination of SLN altered recommendations in half of the dogs compared with the previous standard of care. CLINICAL SIGNIFICANCE: Indirect computed tomographic lymphangiography and SLN excision should be considered as a new standard for dogs with MCT.

Clinical, clinicopathologic, and hepatic histopathologic features associated with probable ketoconazole-induced liver injury in dogs: 15 cases (2015-2018).

OBJECTIVE: To characterize clinical, clinicopathologic, and hepatic histopathologic features and outcome for dogs with probable ketoconazole-induced liver injury. ANIMALS: 15 dogs with suspected ketoconazole-induced liver injury that underwent liver biopsy. PROCEDURES: Medical record data were summarized regarding signalment, clinical signs, clinicopathologic and hepatic histopathologic findings, concurrent medications, ketoconazole dose, treatment duration, and outcome. RESULTS: Median age and body weight were 8.2 years (range, 5 to 15 years) and 13.0 kg (28.6 lb; range, 8.2 to 38.0 kg [18.0 to 83.6 lb]), respectively. The most common breed was Cocker Spaniel (n = 5). All dogs received ketoconazole to treat cutaneous Malassezia infections. Median daily ketoconazole dose was 7.8 mg/kg (3.5 mg/lb; range, 4.4 to 26.0 mg/kg [2.0 to 11.8 mg/lb]), PO. Treatment duration ranged from 0.3 to 100 cumulative weeks (intermittent cyclic administration in some dogs); 6 dogs were treated for ≤ 10 days. Common clinical signs included lethargy, anorexia, and vomiting. All dogs developed high serum liver enzyme activities. Hepatic histopathologic findings included variable lobular injury, mixed inflammatory infiltrates, and conspicuous aggregates of ceroid-lipofuscin-engorged macrophages that marked regions of parenchymal damage. Five dogs developed chronic hepatitis, including 3 with pyogranulomatous inflammation. Of the 10 dogs reported to have died at last follow-up, survival time after illness onset ranged from 0.5 to 165 weeks, with 7 dogs dying of liver-related causes. CONCLUSIONS AND CLINICAL RELEVANCE: Findings for dogs with hepatotoxicosis circumstantially associated with ketoconazole treatment suggested proactive monitoring of serum liver enzyme activities is advisable before and sequentially after initiation of such treatment.

Progression of aural plaques to squamous cell carcinoma in a horse.

BACKGROUND: Aural plaques are associated with and thought to be caused by one or more Equus caballus papillomaviruses (EcPV). Aural plaques have not previously been reported to be associated with squamous cell carcinoma (SCC). HYPOTHESIS/OBJECTIVES: To describe a horse with aural plaques and squamous cell carcinoma (SCC) on the right pinna. ANIMALS: A 28-year-old thoroughbred gelding presented for multiple plaques and a mass on the right pinna. METHODS AND MATERIALS: Pinnal resection, histopathological investigation, multiple conventional PCRs for papillomavirus DNA and Sanger sequencing were performed. RESULTS: Multiple, raised, pale tan, fronded plaques covered 60% of the concave surface of the right pinna. Focally these plaques coalesced into an exophytic ulcerated mass near the base of the pinna. Multiple aural plaques and a SCC were diagnosed histopathologically. EcPV4 was detected via PCR in a sample of the SCC. CONCLUSIONS AND CLINICAL IMPORTANCE: This report demonstrates the possibility of malignant transformation from aural plaques to SCC on the pinna of a horse. To the best of the authors' knowledge, this is the first report of EcPV4 associated with SCC.

Combined carbon dioxide laser and cryosurgical ablation of rostral nasal septum squamous cell carcinoma in 10 dogs.

BACKGROUND: Squamous cell carcinoma (SCC) is the most commonly reported neoplasm of the nasal planum and treatment is focused on localized disease. Rostral maxillectomy and/or nasal planectomy are considered standard of care for excision of nasal planum SCC; however, the cosmetic outcome of these procedures can be deemed unacceptable by many pet owners. OBJECTIVES: The study aim was to evaluate the efficacy of combination carbon dioxide (CO2 ) laser surgery and cryosurgery as a palliative treatment modality in dogs with nasal SCCs. ANIMALS: Ten client-owned dogs with nasal SCC were included: seven neutered males, two spayed females and one intact male, with a median age of 12.5 years (range 9-15 years). METHODS AND MATERIALS: Tumour CO2 laser ablation was followed by cryosurgical ablation of the visible tumour, adjacent and subjacent tissue. Three rapid freeze-slow thaw cycles were performed. RESULTS: Eight of 10 dogs were Labrador retrievers. The ages ranged from 9 to 14 years. Overall median survival time was 260 days with two dogs still alive at the time of writing. CONCLUSIONS AND CLINICAL IMPORTANCE: Combined CO2 laser and cryosurgical ablation was practical, cost-effective and provided an excellent aesthetic outcome in dogs with SCCs restricted to the nasal septum, while providing acceptable palliation of local disease.

Charcot-Leyden crystals: do they exist in veterinary species? A case report and literature review.

The Charcot-Leyden crystal (CLC) is a major human eosinophil protein that readily crystallizes; these crystals are common in eosinophilic diseases. Although anecdotal existence of these crystals is known in veterinary pathology, definitive reports do not exist, to our knowledge. We identified eosinophilic crystals in a laryngeal myxosarcoma from a 2-y-old, spayed female, Labrador Retriever dog that were tentatively interpreted as CLCs. However, Ziehl-Neelsen acid-fast stain was negative, arguing against CLCs. The crystals stained red with Masson trichrome, precluding collagen. Periodic acid-Schiff and alcian blue were negative. The crystals stained positively with Okajima, and no myoglobin immunoreactivity was detected, supporting their identity as hemoglobin crystals. In the absence of a hematologic abnormality, these crystals were interpreted to be abnormal hemoglobin breakdown products. Protein sequence comparison was pursued to determine whether a protein similar to CLC exists in mammals. Only 3 nonhuman primate species, the Sumatran orangutan ( Pongo abelii), rhesus macaque ( Macaca mulatta), and cynomolgus monkey ( Macaca fascicularis), had a sequence similarity of >80%. Of the crystal-forming residues, 12 of 54 (22%) were different in the Sumatran orangutan and 15 of 54 (28%) were different in the Macaca spp., which may affect the crystallization process. The lack of reports of CLCs in nonhuman species and our results collectively suggest that CLCs are human-specific.

Characterization of aminoaciduria and hypoaminoacidemia in dogs with hepatocutaneous syndrome.

OBJECTIVE To characterize aminoaciduria and plasma amino acid concentrations in dogs with hepatocutaneous syndrome (HCS). ANIMALS 20 client-owned dogs of various breeds and ages. PROCEDURES HCS was definitively diagnosed on the basis of liver biopsy specimens (n = 12), gross and histologic appearance of skin lesions (4), and examination of skin and liver biopsy specimens (2) and presumptively diagnosed on the basis of cutaneous lesions with compatible clinicopathologic and hepatic ultrasonographic (honeycomb or Swiss cheese pattern) findings (2). Amino acid concentrations in heparinized plasma and urine (samples obtained within 8 hours of each other) were measured by use of ion exchange chromatography. Urine creatinine concentration was used to normalize urine amino acid concentrations. Plasma amino acid values were compared relative to mean reference values; urine-corrected amino acid values were compared relative to maximal reference values. RESULTS All dogs had generalized hypoaminoacidemia, with numerous amino acid concentrations < 50% of mean reference values. The most consistent and severe abnormalities involved glutamine, proline, cysteine, and hydroxyproline, and all dogs had marked lysinuria. Urine amino acids exceeding maximum reference values (value > 1.0) included lysine, 1-methylhistidine, and proline. CONCLUSIONS AND CLINICAL RELEVANCE Hypoaminoacidemia in dogs with HCS prominently involved amino acids associated with the urea cycle and synthesis of glutathione and collagen. Marked lysinuria and prolinuria implicated dysfunction of specific amino acid transporters and wasting of amino acids essential for collagen synthesis. These findings may provide a means for tailoring nutritional support and for facilitating HCS diagnosis.

Atypical cutaneous cryptococcosis in four cats in the USA.

BACKGROUND: Cryptococcosis is an uncommon fungal infection in humans and mammals. Occasionally, cryptococcosis manifests as cutaneous lesions, either as an extension of nasal disease or as stand alone lesions unassociated with the nose. Histologically, these lesions are typically characterized by abundant organisms with mild granulomatous dermatitis. Herein, four feline cases of atypical cutaneous cryptococcal infections are described. METHODS: Skin punch biopsies from four client owned cats were submitted for histological evaluation between 2006 and 2015. Histological examination, including histochemical stains, was performed in all cases. Immunohistochemical stains and PCR were performed in three of four cases. Fungal culture was performed in two cases and transmission electron microscopy was performed in one case. RESULTS: Grossly, the cutaneous lesions were papular to nodular with occasional ulceration and were located predominantly on the trunk. Histological examination revealed severe granulomatous to pyogranulomatous and eosinophilic dermatitis with rare, capsule-deficient yeasts. Immunohistochemistry, PCR and fungal culture confirmed Cryptococcus spp. to be the aetiological agent in these cases. CONCLUSIONS AND CLINICAL IMPORTANCE: In cutaneous lesions, capsule-deficient strains of Cryptococcus spp. may induce a severe inflammatory response with rare intralesional organisms that may not be readily identified on routine haematoxylin and eosin stained slides. Special stains with careful examination and ancillary tests (PCR, immunohistochemistry, fungal culture or antigen testing) should be performed when pyogranulomatous and eosinophilic dermatitis is encountered without an identifiable cause.

Sheep-Associated Malignant Catarrhal Fever-Like Skin Disease in a Free-Ranging Bighorn Sheep ( Ovis canadensis ), Alberta, Canada.

Malignant catarrhal fever-like clinical disease was diagnosed in a free-ranging bighorn sheep ( Ovis canadensis ) from Alberta, Canada, in June 2015. Antemortem and gross pathology findings included muscle atrophy, marked weight loss, and bilaterally symmetric alopecia with hyperpigmentation and crusting over the face, medial surfaces of the pinnae, dorsal trunk, distal limbs, perineal area, and tail. Histologically, the skin lesions were characterized by granulomatous mural folliculitis with numerous multinucleated giant cells and fewer lymphocytes and eosinophils consistent with previous reports of chronic ovine herpesvirus-2 (OvHV-2) infection. Multiple skin samples were positive for OvHV-2 DNA on PCR, and on partial sequencing of the viral DNA, there was 94% homology with reference GenBank OvHV-2. Quantitative PCR confirmed an increased level of OvHV-2 DNA in the lesional skin tissues. Based on exclusion of other disease processes, gross and histological lesions, PCR, and viral DNA sequencing results, a diagnosis of OvHV-2-mediated malignant catarrhal fever-like dermatitis was made.

Hepatocutaneous syndrome in Shih Tzus: 31 cases (1996-2014).

OBJECTIVE: To characterize findings in Shih Tzus with progressive superficial necrolytic dermatitis and degenerative vacuolar hepatopathy consistent with hepatocutaneous syndrome. DESIGN: Retrospective case series. ANIMALS: 31 Shih Tzus. PROCEDURES: Medical records were reviewed to obtain information on signalment, history, treatment, outcome, and results of clinicopathologic testing, abdominal ultrasonography, and histologic examination of skin and liver specimens. A pedigree analysis was performed. RESULTS: There were 16 males and 15 females. Median age at the time of diagnosis was 8 years (range, 5 to 14 years). Common clinical signs included lethargy, inappetence, weight loss, and lameness. Twenty-five dogs had cutaneous lesions consistent with hepatocutaneous syndrome; the remaining 6 initially only had hepatic abnormalities, but 3 of the 6 subsequently developed cutaneous lesions. Common clinicopathologic abnormalities included microcytosis (15/24 [63%] dogs) and high serum alkaline phosphatase activity (24/24 [100%] dogs). Hepatic ultrasonographic findings included a hyperechoic or heteroechoic appearance to the parenchyma with innumerable hypoechoic nodules. Histologic hepatic lesions consisted of degenerative vacuolar (glycogen and lipid) hepatopathy associated with minimally fibrotic to nonfibrotic, noninflammatory, proliferative nodules. Pedigree analysis confirmed a common ancestry in 12 of 18 dogs. Median survival time was 3 months (range, 1 to 36 months). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that HCS may have a heritable component in Shih Tzus, although the condition may also be identified in Shih Tzus without affected relatives. Clinical, clinicopathologic, ultrasonographic, and histologic abnormalities in affected Shih Tzus were similar to those previously reported for dogs of other breeds with HCS.

Resident lymphocytes in the dermis of the normal dorsolateral thoracic skin of alpacas.

BACKGROUND: Small numbers of resident T lymphocytes are present in the dermis of normal skin of humans, cattle and sheep. HYPOTHESIS/OBJECTIVES: We wanted to determine the prevalence, numbers and immunophenotype of lymphocytes in the dermis of healthy skin from alpacas. ANIMALS: Skin biopsy specimens were collected from the dorsolateral thorax of 31 alpacas with normal skin. METHODS: Skin biopsy specimens were evaluated for the prevalence and numbers of CD3+ and CD79a+ lymphocytes. RESULTS: Resident CD3+ and CD79a+ lymphocytes were found around the superficial and deep dermal blood vessels. The CD3+ lymphocytes were more numerous than CD79a+ lymphocytes. Both CD3+ and CD79a+ lymphocytes were more numerous around superficial dermal blood vessels. CONCLUSIONS AND CLINICAL IMPORTANCE: Resident CD3+ and CD79a+ lymphocytes are present around superficial and deep dermal blood vessels in normal skin from alpacas; hence, the presence of lymphocytes in these locations without obvious features of inflammation must be interpreted cautiously when evaluating skin biopsy specimens from alpacas with skin disease.

Scaling dermatosis in three dogs associated with abnormal sebaceous gland differentiation.

BACKGROUND: Abnormal sebaceous gland differentiation, so-called 'sebaceous gland dysplasia', is a rare condition described in the dog and the cat. Although little is known about this condition, it is thought that a genetic defect causes abnormal sebaceous gland development. Clinically, this condition occurs in young cats and dogs and is characterized by variable degrees of adherent scale, hair casts, poor coat quality and hypotrichosis. HYPOTHESIS/OBJECTIVE: Here, we describe the clinical presentation and treatment of three adult dogs with abnormal sebaceous gland differentiation. ANIMALS: Three adult dogs presented with a keratinization defect characterized by progressive scaling, hair casts, dull, dry, brittle hair coat and hypotrichosis beginning in puppyhood to early adulthood. METHODS: Multiple 6 mm punch skin biopsy samples were obtained from each dog. Treatments included various topical keratomodulatory agents, oral essential fatty acids and oral vitamin A. RESULTS: Histologically, all sebaceous glands were small and composed of a mixture of irregularly clustered basal reserve cells and mature sebocytes. With therapy, two of the dogs showed moderate to marked clinical improvement in scaling, hair casts and hair coat quality. CONCLUSIONS AND CLINICAL IMPORTANCE: Although rare, 'sebaceous gland dysplasia' should be considered in cases where a primary keratinization defect is suspected. Given that abnormal sebaceous differentiation is a structural defect of the skin, treatment must be maintained and is aimed at ameliorating the clinical signs rather than curing the disease.

Comparison of the levels of Equus caballus papillomavirus type 2 (EcPV-2) DNA in equine squamous cell carcinomas and non-cancerous tissues using quantitative PCR.

Equus caballus papillomavirus type 2 (EcPV-2) infection has been associated with equine genital squamous cell carcinomas (SCCs). However, quantitative PCR (qPCR) has not been performed to determine viral copy numbers within these lesions. Additionally, the frequency with which EcPV-2 can be detected in other common sites of equine SCC development remains uncertain. The aim of this study was to develop a qPCR assay to estimate the viral load in a variety of equine tissue samples. These included 40 SCC lesions, 19 penile non-SCC or precursor disease lesions, and 222 tissues without observable lesions from SCC-prone sites on clinically normal horses. EcPV-2 DNA was present significantly more frequently, and in higher copy numbers, in equine penile SCC lesions than in either healthy penile mucosa or non-SCC penile lesions. This supports the hypothesis that EcPV-2 is involved in development of penile SCCs and suggests that penile EcPV-2 infection is rare in the absence of SCCs. Samples of normal vulval mucosa rarely contained EcPV-2 DNA and none of the nictitating membrane samples contained EcPV-2 DNA, indicating that asymptomatic EcPV-2 infection is uncommon at these sites. EcPV-2 DNA was detected in a proportion of both SCCs and normal samples from the oral cavity or pharynx, although there were no significant differences in the rate of infection or viral copy number between the SCCs and the normal mucosal samples. As such, the role of EcPV-2 in development of SCCs in this location remains to be established.