Dermoscopic findings and comparison of usefulness of longitudinal versus transversal sections in the histological diagnosis of alopecia X.

BACKGROUND: A combination of dermoscopic and histological findings may provide useful information for the diagnosis of hair follicle diseases. However, there are no studies on dermoscopic-histopathological correlations in dogs affected by alopecia X, and comparison of longitudinal versus transversal sectioning of skin biopsy specimens in the assessment of this hair loss disorder has not been thoroughly investigated. HYPOTHESIS/OBJECTIVES: The aim of this study was to correlate dermoscopic and histological features using both longitudinal and transversal sectioning of skin biopsy samples to gain additional information for the diagnosis of alopecia X. ANIMALS: Nineteen Pomeranian dogs affected by alopecia X and five healthy Pomeranians as controls. MATERIALS AND METHODS: Dermoscopic-histological correlation was performed within the diseased group, whereas histological comparisons against controls. The demographic and clinical characteristics also were related to the histological findings. RESULTS: The dermoscopic findings revealed scattered, thinned, short hairs mixed with amorphous keratoseborrhoeic-like material (follicular plugging), perifollicular and intrafollicular scaling, and hyperpigmentation varying from pinpoint black spots to a diffuse texture. Dermoscopic findings correlated with histological findings for selected qualitative and quantitative findings. The usefulness of transversal sections was demonstrated in accurately determining the hair follicular density and counts, growth arrest phases and in identifying mineralisation of hair follicle basement membrane when compared to the longitudinal. Conversely, no correlations between histological findings and demographic and clinical characteristics were detected. CONCLUSIONS AND CLINICAL RELEVANCE: These data provide evidence of the usefulness of dermoscopic evaluation as an accessory diagnostic tool and of transversal sections of skin biopsies as complementary to the diagnosis of alopecia X.

Clinical, histopathological, and molecular characterization of canine pigmented viral plaques.

Canine pigmented viral plaques (PVPs) are proliferative epidermal lesions caused by canine papillomaviruses (CPVs). Although the lesions are benign, neoplastic transformation has been reported. Cases reported in the literature are few and mainly focused on genome sequencing. The aim of this study was to collect data on the epidemiology, clinicopathological features, and genotyping of PVPs. Fifty-five canine PVPs were retrospectively retrieved and histologically evaluated. Follow-up was available for 33 cases. The median age was 6.5 years and pugs were the most represented breed (25%). There were 4 clinical presentations: a single lesion (24%), multiple lesions (75%) in one (41%) or different sites (34%), and generalized lesions all over the body (24%). The abdomen and axillae were the most common sites. In single lesions, no recurrence was observed after conventional surgery, whereas different medical treatments reported for multiple lesions were not successful. Spontaneous regression was reported in 3 cases. Neoplasia in contiguity with PVPs was seen in 5 of 55 lesions (9%), and 1 dog was euthanized due to invasive squamous cell carcinoma (SCC). The most useful histopathological features for diagnosis were scalloped profile, epidermal spikes, hypergranulosis, and hyperpigmentation. L1 immunolabeling was present in 14 of 16 cases (87%). Sequencing revealed that 10 of 16 cases were associated with CPV-9 (71%), 2 cases were associated with CPV-4 (14%), and 2 cases were associated with CPV-8 (14%). In conclusion, this represents a large cohort study on canine PVPs reporting data on clinicopathological features, therapy, outcome, and the type of CPV involved for the first time in Italy.

Trehalose Treatment in Zebrafish Model of Lafora Disease.

Mutations in the EPM2A gene encoding laforin cause Lafora disease (LD), a progressive myoclonic epilepsy characterized by drug-resistant seizures and progressive neurological impairment. To date, rodents are the only available models for studying LD; however, their use for drug screening is limited by regulatory restrictions and high breeding costs. To investigate the role of laforin loss of function in early neurodevelopment, and to screen for possible new compounds for treating the disorder, we developed a zebrafish model of LD. Our results showed the epm2a-/- zebrafish to be a faithful model of LD, exhibiting the main disease features, namely motor impairment and neuronal hyperexcitability with spontaneous seizures. The model also showed increased inflammatory response and apoptotic death, as well as an altered autophagy pathway that occurs early in development and likely contributes to the disease progression. Early administration of trehalose was found to be effective for rescuing motor impairment and neuronal hyperexcitability associated with seizures. Our study adds a new tool for investigating LD and might help to identify new treatment opportunities.

Gross and histological findings in the canine placenta and amnion at term: What's normal, abnormal or pathological?

The canine placenta is an underexamined organ. Placental abnormalities can affect foetus development and may be responsible for a low weight of the infant at birth; however, knowledge on their clinical significance in the canine species is limited. We aimed to describe macroscopic and microscopic findings in the canine placenta and amnion at term in clinically uncomplicated pregnancies and to evaluate their relationship with birth weight of healthy puppies. During natural delivery or C-section, the birth weight of 82 puppies was recorded, 72 placentas and 66 amnions were recovered. The foetal and maternal surfaces of the placental girdle, marginal haematoma and amnion were evaluated. Each gross finding was recorded, morphometrically assessed and sampled for histological diagnosis. Furthermore, specimens of placenta and amnion were collected from representative areas and microscopic deviations from normal structure were evaluated in haematoxylin and eosin sections. Gross examination revealed 'abnormalities' in the 75.4% of the collected placentas. Necrosis was the gross change most commonly observed in the placental girdle (72.5%). Congestion (17.4%) and clotted blood/fibrinoid material (2.9%) were also observed. No gross changes of either the marginal haematoma or the amnion were recorded. Histologically, placental girdle showed necrosis (62.3%), mineralization (52.2%), congestion (36.2%) and neutrophilic infiltration (27.5%). Marginal haematoma exhibited mineralization (11.6%) and neutrophils (29%), while necrotic foci were rarely observed (4.3%). In the amnion, the most frequent alteration observed was hypertrophy of the epithelium (35.9%) followed by oedema (31.2%), mineralized foci (28.1%), fibrosis (23.4%), congestion (15.6%) and more rarely neutrophils (12.5%). Puppies' birth weight was not statistically affected by either gross or histological abnormalities. Our study revealed that macroscopic and microscopic 'abnormalities' of the placenta and amnion may be common in uncomplicated pregnancies at term; however, no implications on puppies' birth weight were observed. Deviations from 'normal' morphology of canine foetal adnexa warrant further investigation to assess their clinical implications if present.

Linear arrector pili muscle hamartoma on the tail of a sphynx cat.

Arrector pili muscle (APM) hamartoma is reported in humans and dogs. We describe a linear APM hamartoma in a sphynx cat. The lesion was characterized by multiple nodules distributed linearly along the tail, made of randomly arranged hypertrophic smooth muscles, the size of which tended to wax-and-wane during a one year follow-up.

L'hamartome du muscle arrecteur du poil (APM) est décrit chez l'homme et chez le chien. Nous décrivons un hamartome APM linéaire chez un chat sphynx. La lésion était caractérisée par de multiples nodules répartis en ligne sur la queue, composés de fibres musculaires lisses hypertrophiques désordonnées, dont la taille a évolué par poussée au cours d'une période de suivi d'un an.

El hamartoma del músculo erector piloso(APM) ha sido descrito en humanos y en perros. Describimos un hamartoma APM lineal en un gato esfinge. La lesión se caracterizó por múltiples nódulos distribuidos linealmente a lo largo de la cola, compuestos de músculos lisos hipertróficos dispuestos al azar, cuyo tamaño tendía a fluctuar durante un año de seguimiento.

O hamartoma do músculo eretor do pelo (MEP) é relatado em humanos e cães. Nós descrevemos um hamartoma linear em um gato sphynx. A lesão foi caracterizada por múltiplos nódulos distribuídos linearmente ao longo da cauda, constituídos por músculos lisos hipertróficos dispostos aleatoriamente, cujo tamanho tendia a aumentar e diminuir ao longo do acompanhamento de um ano.

Clinical, haematological and biochemical findings in tigers infected by Leishmania infantum.

BACKGROUND: A large number of animal species are susceptible to Leishmania infantum (Kinetoplastida, Trypanosomatidae) in endemic areas, including domestic and wild felids such as tigers (Panthera tigris). Knowledge on the infection of this endangered species is still at its infancy, and therefore this study aims to identify clinical presentation and clinicopathological findings of tigers naturally infected by L. infantum. RESULTS: Tigers either L. infantum-positive (group A) or -negative (group B) were apparently healthy or presented visceral leishmaniasis unrelated conditions, except for one animal in which a large non-healing cutaneous lesion was observed. However, histological exam and immunohistochemistry carried out on the lesion excluded the presence of L. infantum amastigotes. Biochemical analysis showed that the average concentration of total proteins, globulins and haptoglobin were significantly higher (p < 0.01, p = 0.01 and p = 0.02, respectively), while the albumin/globulin ratio significantly lower (p = 0.05) in group A compared with group B. The biochemical alterations were partially confirmed by the serum protein electrophoresis results revealing a significant increase in the total protein value (p = 0.01) and hypergammaglobulinemia (p = 0.03) but an unmodified albumin/globulin ratio in group A. CONCLUSIONS: In this study tigers infected by L. infantum have shown to be mainly asymptomatic. The absence of clinical signs may lead veterinarians to overlook leishmaniasis in animals kept in captivity. Therefore, diagnostic and screening tests as serology should be part of routinely surveillance programs to be performed on tigers in zoological gardens located in endemic areas. Though only few protein-related laboratory abnormalities were recorded in infected animals, they could provide diagnostic clues for a first suspicion of L. infantum infection in tigers. Indeed, considering the high risk of zoonotic transmission in heavily frequented environment as zoos, a prompt diagnosis of L. infantum infection is of pivotal importance.

Acral congenital superficial dermal lymphatic malformations in two unrelated cats: clinicopathological, dermoscopic and ultrastructural findings.

BACKGROUND: Cutaneous vascular malformations (CVM) represent a spectrum of human diseases identified at birth or in paediatric patients and classified according to the type of vessel affected. Confusing classification in human medicine has led to misdiagnoses and frequent nomenclature revision. Cutaneous lymphatic malformations (CLM) are reported sporadically in humans. OBJECTIVE: To describe the clinicopathological findings of superficial dermal cutaneous lymphatic malformations (SDCLM) in two cats. ANIMALS: Two unrelated adult domestic short hair cats. METHODS: The two cats were evaluated clinically and with a dermoscope for recurrent swelling and presence of vesicles oozing serosanguineous fluid affecting the right and left hind foot, respectively, since birth. Skin biopsy specimens were collected for histopathological and immunohistochemical evaluation and electron microscopy. RESULTS: A CVM was suspected based on the age of onset, clinical signs, results of diagnostic imaging and histopathological findings. Dermoscopy was used to describe the alterations of the skin surface. The involvement of the lymphatic vessels was confirmed using immunohistochemical findings and electron microscopy. CONCLUSION AND CLINICAL IMPORTANCE: To the best of the authors' knowledge, this is the first description of the clinical, dermoscopic, histopathological and ultrastructural characteristics of SDCLM in cats resembling the human counterpart. SDCLMs are rare conditions and appropriate histopathological and immunohistochemical confirmation is required to avoid misdiagnosis and mistreatment.

Felis catus Papillomavirus Types 1, 2, 3, 4, and 5 in Feline Bowenoid in Situ Carcinoma: An In Situ Hybridization Study.

Several studies based on histopathology or molecular investigations suggest a causal relation between Felis catus papillomavirus (FcaPV-2) infection and bowenoid in situ carcinoma (BISC) in cats. Nevertheless, data on distribution of viral DNA for different F. catus papillomavirus types (FcaPV-1, 2, 3, 4, 5) in precancerous skin lesions are lacking. In this study, incisional and excisional skin biopsies from 18 cats with BISC were investigated for the presence of FcaPV DNA by quantitative polymerase chain reaction (qPCR) and chromogenic in situ hybridization (CISH) using specific probes to detect each of the FcaPVs that have been identified so far. By qPCR analysis, 15 of 18 samples were positive for FcaPV-2, 2 were positive for FcaPV-4, and 1 sample was negative for all FcaPVs studied. Two cases were positive for FcaPV-5 by qPCR only. FcaPV-1 and FcaPV-3 were not detected by either method. CISH positivity for FcaPV-2 and FcaPV-4 was 100% concordant with qPCR. FcaPV-2 CISH signal was observed as nuclear dots within grouped neoplastic keratinocytes in 12 BISCs and in the perilesional skin of 9 biopsies. In 3 of these 9 cases, the signal was not observed within the BISC. FcaPV-4 CISH positivity was detected only within BISCs in 2 cases. The overall rate of concordance for FcaPV detection between PCR and CISH was 97.8%. This study suggests that CISH is a reliable method to detect FcaPV-2 and FcaPV-4 infection in cats and provides useful information on the type, rate, and localization of infected cells.

Aging-associated perifollicular changes and calcium deposition in poodles.

BACKGROUND: It is commonly accepted that canine dystrophic mineralization of the hair follicle glassy membrane can be seen in hyperadrenocorticism and as a senile change in poodles. Pathology textbooks define this change as deposition of calcium salts in the form of basophilic, amorphous, granular material along collagen fibrils. HYPOTHESIS/OBJECTIVES: The aim was to evaluate whether the incidence of the lesion is specific to poodles and if it is always associated with calcium deposition. ANIMALS: One hundred and forty-seven dogs divided into three groups: (i) 91 normal poodles; (ii) 40 dogs of other breeds; and (iii) 16 dogs with clinical/histopathological diagnosis of hyperadrenocorticism. METHODS AND MATERIALS: Retrospective study; with haematoxylin and eosin, and von Kossa staining. RESULTS: Our findings demonstrate that perifollicular changes of the hair follicle glassy membrane of poodles are not always associated with calcium deposition. CONCLUSIONS AND CLINICAL IMPORTANCE: A specific staining is needed to identify true calcium deposition when performing histological examination of the skin of poodles.

Footpad peripheral ganglioneuroblastoma in a dog.

BACKGROUND: Peripheral neuroblastic tumours arising from primitive cells of the cranial and spinal ganglia and from sympathetic ganglion cells of the autonomic nervous system include, from most to least differentiated, ganglioneuroma, ganglioneuroblastoma and neuroblastoma. Canine ganglioneuroblastoma has been described in the mediastinum, nasal and oral cavities, as well as in the brain. OBJECTIVE: To describe the clinical and histopathological findings, treatment and follow-up of a primary cutaneous ganglioneuroblastoma affecting the footpad of a dog. ANIMAL: An 8-year-old male German shepherd dog, referred for left forelimb lameness and licking of the footpad, showed thickening of the footpad of digit V with a central nodular lesion. METHODS AND RESULTS: Histopathological and immunohistochemical examination on a surgical skin biopsy specimen showed an infiltrative and highly cellular neoplasm in the deep dermis. The neoplasm was composed of large polyhedral cells with abundant cytoplasm containing Nissl substance that reacted strongly with neuron-specific enolase and neuronal nuclei antigen, spindle cells with indistinct cell borders suggestive of Schwann cells, with a mild S-100 and GFAP immunoreactivity, and rare nests of neuroblasts. The owner agreed to digit amputation. Histologically, a neoplastic multinodular proliferation with morphological findings like those detected in the biopsy was observed, not extended to the surgical margins and without involvement of skeletal bone. No recurrence or metastasis was observed over a period of one year. CONCLUSIONS AND CLINICAL IMPORTANCE: To the best of the authors' knowledge, this is the first report of a primary cutaneous ganglioneuroblastoma in a dog. Ganglioneuroblastoma should be included in the differential diagnoses of canine footpad neoplastic diseases.

Quantitative real time polymerase chain reaction (qRT-PCR) and RNAscope in situ hybridization (RNA-ISH) as effective tools to diagnose feline herpesvirus-1-associated dermatitis.

BACKGROUND: Felid herpesvirus type 1 (FHV-1)-associated dermatitis is characterized by facial and nasal involvement; clinical and histopathological manifestations may overlap with other dermatitides. OBJECTIVE: To evaluate the realibility of qRT-PCR-2- ΔΔC q and RNAscope in situ hybridization (RNA-ISH) methods to diagnose FHV-1-associated dermatitis, in formalin-fixed paraffin-embedded (FFPE) tissues. ANIMALS: Sixteen FFPE samples from cats with facial dermatitis and four controls were studied. METHODS AND MATERIALS: Based on histopathological features, cases were separated into: Group 1, samples with herpetic dermatitis (four); Group 2, samples with nonherpetic facial dermatitis (six); Group 3, samples with facial dermatitis of ambiguous nature (allergic or viral) (six); and Group 4, samples from healthy cats (four). A relative quantification using the 2- ΔΔC q method was used to estimate the "upregulation" of each FHV-1 target viral gene copies (glycoprotein-B and thymidine-kinase) relative to reference gene. Detection of FHV-1 mRNA was performed using the RNAscope 2.5 detection kit. RESULTS: By 2- ΔΔC q analysis, upregulation of both FHV-1 genes was observed in all samples from Group 1 and two of six from Group 3. No upregulation was identified in samples from groups 2 and 4. Positive mRNA hybridization signal was observed in all cases from Group 1 and two cases of Group 3. No positivity was observed in samples from groups 2 and 4. CONCLUSIONS AND CLINICAL IMPORTANCE: QRT-PCR 2-ΔΔCq analysis and RNA-ISH can identify the FHV-1 genome as causative agent of the associated dermatitis, even where inclusion bodies are not detectable. Both techniques are functional in retrospective studies, have greater specificity than conventional PCR, and may be proposed for research and diagnostic purposes.

Evaluation of Ki-67 expression in feline non-ocular melanocytic tumours.

BACKGROUND: Melanomas are rare in cats. The eye is the most commonly involved site, whereas few data are available about feline non-ocular melanomas (NOMs). Ki-67 thresholds with prognostic relevance have been established for canine melanomas, but not in cats. This study was undertaken to investigate the relationship between Ki-67 index, tumour characteristics, and clinical outcome in feline NOMs. Histologic samples were retrospectively reviewed. Amelanotic tumours were admitted upon immunohistochemical positivity for Melan A or S100. Evaluated parameters included morphological diagnosis, histotype, junctional activity, degree of pigmentation, vascular invasion, lymphocytic infiltrate, necrosis, mitotic count (MC) and Ki-67 index. Pigmented tumours were bleached before evaluation. Clinical and follow-up information were retrieved via telephone interviews with the referring veterinarians. RESULTS: Fifty tumours located in skin (n = 33) and mucosae (n = 17) were included. Forty-eight percent and 95% of amelanotic tumours (n = 21) stained positive for Melan A and S100, respectively. Most achromic tumours were mucosal (P < 0.001, Fisher's exact test) and presented a spindle cell morphology (P = 0.002; Fisher's exact test). MC and Ki-67 index were significantly correlated (P < 0.001; R = 0.67; Spearman's rank correlation); median values were 15 (range, 0-153) and 28% (range, 1-78%), respectively. Both were significantly higher in spindle cell melanomas, in tumours lacking junctional activity and in poorly-pigmented tumours. Follow-up information was available for 33 cats (66%). Variables related with a poor clinical outcome included mucosal location, tumour size, spindle, balloon and signet ring cell histotypes, low pigmentation, MC > 5, Ki-67 > 20% and lack of treatment administration. On multivariable analysis, only tumour histotype and treatment retained prognostic significance. CONCLUSIONS: Although the majority of feline NOMs behave aggressively, Ki-67 index, together with other parameters, may contribute to prognostic assessment. Prospective studies on homogeneous populations are warranted to identify reliable threshold values for this marker.

A retrospective histopathological, immunohistochemical and molecular study of the presence of Leishmania spp. in the skin of cats with head and neck ulcerative dermatitis.

BACKGROUND: Head and neck ulcers in cats can arise from allergic and nonallergic disorders, including feline leishmaniosis (FeL). It is important to rule out this aetiological agent in regions that are endemic for canine leishmaniosis, because the drugs used to treat immune-mediated disorders of cats can be contraindicated in the setting of infection. HYPOTHESIS/OBJECTIVES: The aim of this study was to evaluate the skin of cats with ulcerative dermatitis of the head or neck for evidence of Leishmania infection using combined immunohistochemistry (IHC) and Polymerase Chain Reaction (PCR). An IHC for tissue histiocytes was also utilized because leishmaniosis may provoke a histiocytic inflammatory response. ANIMALS: Twenty seven cats with head and/or neck ulcers. METHODS: Skin biopsy specimens were examined for the presence of Leishmania spp. by routine histopathological evaluation and IHC using a polyclonal anti-Leishmania antibody, and by quantitative PCR (qPCR). The ionized calcium-binding adapter molecule-1 (IBA-1) antibody was used to immunolocalize histiocytes. Selected history and clinical data were recorded. RESULTS: All specimens showed a superficial mid-perivascular mixed inflammatory infiltrate. The presence of histiocytes was confirmed in 23 of 27 cases with the IBA-1 antibody. Immunohistochemistry and qPCR techniques confirmed the absence of Leishmania in all cases. CONCLUSIONS AND CLINICAL IMPORTANCE: Leishmania did not seem to play a role in the pathogenesis of feline ulcerative dermatitis of the head and neck in the subjects studied, despite a lifestyle potentially associated with infection. Histiocytic infiltration of tissue is not a specific marker for Leishmania infection in this population.

Cannabinoid receptor types 1 and 2 and peroxisome proliferator-activated receptor-α: distribution in the skin of clinically healthy cats and cats with hypersensitivity dermatitis.

BACKGROUND: Cannabinoid receptors and peroxisome proliferator-activated receptor-alpha (PPAR-α) are gaining recognition as potential therapeutic targets for the treatment of skin disorders. HYPOTHESIS/OBJECTIVES: The aim of this study was to investigate the distribution of cannabinoid type 1 and 2 receptors (CBR1 and CBR2) and PPAR-α in feline skin and verify whether changes occur in the course of hypersensitivity dermatitis. ANIMALS: Twelve privately owned cats. Skin samples were obtained from five healthy cats with no skin lesions and seven cats clinically diagnosed with hypersensitivity dermatitis. METHODS AND MATERIALS: Haematoxylin and eosin stained skin sections were investigated for histopathological changes. Indirect immunofluorescence for CBR1, CBR2 and PPAR-α was performed on paraffin-embedded sections, and antibody specificity tested by Western blot analysis. RESULTS: Skin samples from cats with hypersensitivity dermatitis were all histopathologically diagnosed with eosinophilic dermatitis. CB receptors and PPAR-α were distributed throughout the skin in both healthy and allergic cats. In normal feline skin, these receptors were mainly distributed in the epithelial compartment. Receptor expression increased in hypersensitivity compared to healthy skin, with the main distribution changes being suprabasal for CBR1, dermal for CBR2 and marked expression of PPAR-α in hyperplastic epidermis and perivascular infiltrate. CONCLUSIONS AND CLINICAL IMPORTANCE: Increased expression of cannabinoid receptors in the skin of cats with hypersensitivity dermatitis suggests an endogenous protective strategy and may support the use of natural cannabinoid receptor or PPAR-α agonists to treat feline hypersensitivity dermatitis.

Filarial infection caused by Onchocerca boehmi (Supperer, 1953) in a horse from Italy.

Equids can be infected by a range of skin-dwelling filarial nematodes, including four species of the genus Onchocerca. Current literature on equine onchocercosis is fragmentary and often limited to isolated case reports. The present study aimed to describe a clinical case of equine onchocercosis caused by Onchocerca boehmi (Supperer, 1953) (syn. Elaeophora boehmi) in an 8-year-old gelding Belgian show jumper from northern Italy. The horse was presented with a firm and painless mass on the proximal third of the right metacarpal region. Ultrasound examination showed a peritendinous enlargement around the palmaro-lateral area of the tendons, characterized by an elongated hypoechoic and well-defined structure, embedding a coiled hyperechoic line. The metacarpal nodule was resected and histologically examined. Fragments of a parasitic nematode were detected, isolated and examined. The morphological analysis allowed identifying the nematode as O. boehmi. In addition, total genomic DNA was extracted from individual fragments using a commercial kit for the nematode identification and a comparative sequence analysis of the nematode cytochrome oxidase subunit 1 (cox1) sequence with data available in the GenBankTM database revealed the closest identity (i.e. 91 %) with that of Onchocerca lupi. Thus far, O. boehmi has only been reported in Austria and Iran, and information about its life-cycle and vectors is lacking. The systematic position of this species within the genus Onchocerca, not in Elaeophora where it was originally described, is in concordance with the morphological and molecular analysis. In this article, we describe the first autochthonous case of equine onchocercosis in Italy caused by O. boehmi and discuss novel parasitological, clinical, and pathological data on these pathogens of horses.

Ultramicronized palmitoylethanolamide counteracts the effects of compound 48/80 in a canine skin organ culture model.

BACKGROUND: Ultramicronized palmitoylethanolamide (PEA-um) has been reported to reduce pruritus and skin lesions in dogs with moderate atopic dermatitis and pruritus. HYPOTHESIS/OBJECTIVES: A canine ex vivo skin model was used to investigate the ability of PEA-um to counteract changes induced by compound 48/80, a well-known secretagogue that causes mast cell degranulation. ANIMALS: Normal skin was obtained from three donor dogs subjected to surgery for reasons unrelated to the study. METHODS: Cultured skin biopsy samples in triplicate were treated with 10 and 100 µg/mL compound 48/80, without or with 30 µM PEA-um. Mast cell (MC) degranulation, histamine release into the culture medium, local microvascular dilatation, epidermal thickness, keratinocyte proliferation and epidermal differentiation markers were evaluated. RESULTS: Exposure of the skin organ culture to PEA-um 24 h before and 72 h concomitantly to compound 48/80 resulted in a significant decrease of degranulating MCs. PEA-um also reduced the histamine content in the culture medium by half, although the effect did not reach statistical significance. PEA-um significantly counteracted vasodilation induced by 100 µg/mL compound 48/80. Finally, PEA-um alone did not induce changes in epidermal thickness, differentiation markers, keratinocyte proliferation, MC density and/or degranulation. CONCLUSIONS AND CLINICAL IMPORTANCE: Collectively, these results support the protective action PEA-um on the skin of dogs undergoing allergic changes.

Two cases of feline paraneoplastic alopecia associated with a neuroendocrine pancreatic neoplasia and a hepatosplenic plasma cell tumour.

BACKGROUND: Feline paraneoplastic alopecia (FPA) is a rare condition listed among the cutaneous paraneoplastic syndromes, which occurs in association with pancreatic carcinoma, cholangiocarcinoma, hepatocellular carcinoma and metastatic intestinal carcinoma. OBJECTIVES: To describe the clinicopathological findings of paraneoplastic alopecia in two cats each with an uncommon tumour not previously reported in association with FPA. ANIMALS: Paraneoplastic alopecia was associated with neuroendocrine pancreatic neoplasia in a Persian cat and with a hepatosplenic plasma cell tumour in a domestic short hair cat. RESULTS: FPA was suspected based on age, rapid onset of clinical signs, ventral distribution of alopecia, shiny appearance of the skin and telogenization/miniaturization of the follicles on histopathology. The nature of the tumours was determined through cytology, postmortem, histopathological and immunohistochemical examination, and capillary immunoelectrophoresis. A causative association between the skin lesions and the tumour was suggested by clinical and histopathological features shared with previously published cases. CONCLUSIONS AND CLINICAL IMPORTANCE: Pancreatic neuroendocrine and plasma cell tumour should be considered as differential diagnoses when evaluating FPA.

Pustular dermatitis in dogs affected by leishmaniosis: 22 cases.

BACKGROUND: Skin lesions in canine leishmaniosis (CanL) are diverse, including exfoliative, ulcerative, nodular and papular dermatitides. An uncommon pustular form has also been reported. HYPOTHESES/OBJECTIVES: We hypothesized that CanL infection can produce a pustular reaction pattern in the skin of dogs. The aim of this retrospective study was to describe the clinicopathological features of dogs with CanL infection and pustular dermatitis, and correlate them with response to therapy. ANIMALS: Twenty two affected dogs. METHODS: Retrospective review of medical records and examination of archived biopsy materials or previously processed glass slides was performed. Cytological examinations had been recorded for all cases. Specimens were available for histopathological examination in 17 of 22 cases and for immunohistochemical detection of Leishmania amastigotes in 13 of 22 cases. RESULTS: All dogs presented with multifocal to diffuse pustular dermatitis. CanL was diagnosed by IFAT serology (20 cases), bone marrow cytology (one case) or bone marrow PCR (one case). Cytological and/or histopathological examinations revealed acantholytic keratinocytes within pustules in 18 of 22 cases. Bacterial and fungal cultures were not performed. Leishmania amastigotes were identified by histopathology within the dermis in three cases; immunohistochemistry was positive in four cases. All dogs underwent concurrent anti-leishmanial and immunosuppressive therapy to control the pustular dermatitis, with favourable outcome in 11 of 22 cases. CONCLUSIONS AND CLINICAL IMPORTANCE: Due to the retrospective nature of this study it is not possible to either accept or reject the hypothesis that CanL is the direct cause of pustular dermatitis.

Efficacy of low-level laser therapy on hair regrowth in dogs with noninflammatory alopecia: a pilot study.

BACKGROUND: Canine noninflammatory alopecia (CNA) is a heterogeneous group of skin diseases with different underlying pathogenesis. The therapeutic approach is challenging, and new options for treatment are desirable. HYPOTHESIS/OBJECTIVES: To test the clinical efficacy of low-level laser therapy (LLLT) on hair regrowth in CNA. ANIMALS: Seven dogs of different ages, breeds and genders with a clinical and histopathological diagnosis of noninflammatory alopecia. METHODS: Each dog was treated twice weekly for a maximum of 2 months with a therapeutic laser producing the following three different wavelengths emerging simultaneously from 21 foci: 13 × 16 mW, 470 nm; 4 × 50 mW, 685 nm; and 4 × 200 mW, 830 nm. The fluence given was 3 J/cm(2) , frequency 5 Hz, amplitude of the irradiated area was 25 cm(2) and application time was 1.34 min. A predetermined alopecic area was left untreated and served as a control area. From one dog, post-treatment biopsies of treated and untreated sites were obtained for histological evaluation of hair density and the percentage of haired and nonhaired follicles. RESULTS: At the end of the study, coat regrowth was greatly improved in six of seven animals and improved in one of seven. By morphometry, the area occupied by hair follicles was 18% in the treated sample and 11% in the untreated one (11%); haired follicles were (per area) 93% in the treated sample and only 9% in the control sample. CONCLUSIONS AND CLINICAL IMPORTANCE: Our clinical and histological data document promising effects of LLLT on hair regrowth in CNA. Further studies investigating the biological mechanism underlying the effect of LLLT on hair follicle cycling are warranted.

MITE INFECTION IN A MASKED PALM CIVET (PAGUMA LARVATA) TREATED BY SELAMECTIN (STRONGHOLD®, PFIZER LTD.).

The masked palm civet (Paguma larvata) is a small Asian mammal (order Carnivora, family Viverridae) uncommon in Italy. Limited information is available about management and sanitary maintenance in captivity. A 4-mo-old masked palm civet presented with pruritus, itch, scratching, and disorexia. On physical examination, alopecia and crusts were detected on the ventral and lateral trunk, tail, legs, and lips. Skin scrapings and cytology revealed Notoedres spp. and bacterial infection. On histopathology, parasitic dermatitis was observed with the presence of a Sarcoptidae mite and Demodex spp. Selamectin spot-on (15 mg/kg every 2 wk, three applications) and marbofloxacin per os (2.5 mg/kg once daily for 2 wk) were administered, and the animal recovered in 1 mo. With the good response to this therapy, a notoedric mange was thought to be the main problem. This is the first report about the use of selamectin to treat a mite infection in masked palm civet.