Detection of Leishmania spp. in Chronic Dermatitis: Retrospective Study in Exposed Horse Populations

Leishmania infantum is a protozoan causing human zoonotic visceral leishmaniasis (ZVL) and visceral–cutaneous canine leishmaniosis (CanL) in the Mediterranean Basin. L. infantum is able to infect a large number of wild and domestic species, including cats, dogs, and horses. Since the 1990s, clinical cases of equine leishmaniasis (EL), typically characterized by cutaneous forms, have been increasingly diagnosed worldwide. The aim of the present study was to evaluate the presence of clinical forms of EL in CanL-endemic areas in Italy, where exposure of equine populations was ascertained from recent serological surveys. For this purpose, formalin-fixed and paraffin-embedded skin biopsies of 47 horses presenting chronic dermatitis compatible with EL were retrospectively selected for the study and subjected to conventional and q-PCR. A singular positivity for L. infantum was found; BLAST analysis of sequence amplicons revealed a 99–100% homology with L. infantum sequences. The histological examination revealed a nodular lymphoplasmacytic and histiocytic infil-trate; immunohistochemistry showed rare macrophages containing numerous positive amastigotes. The present retrospective study reports, for the first time, a case of a cutaneous lesion by L. infantum occurring in an Italian horse. Pathological and healthy skin samples should be investigated on a larger scale to provide information on the potential clinical impact of EL in the practice, and to define the role of horses in epidemiological ZVL and CanL scenarios

Performance of lymph node cytopathology in diagnosis and characterization of lymphoma in dogs

Background: Cytopathology is a minimally invasive and convenient diagnostic procedure, often used as a substitute for histopathology to diagnose and characterize lymphoma in dogs. Objectives: Assess the diagnostic performance of cytopathology in diagnosing lymphoma and its histopathological subtypes in dogs. Animals: One-hundred and sixty-one lymph node samples from 139 dogs with enlarged peripheral lymph nodes. Methods: Based only on cytopathology, 6 examiners independently provided the following interpretations on each sample: (a) lymphoma vs nonlymphoma; (b) grade and phenotype; and (c) World Health Organization (WHO) histopathological subtype. Histopathology and immunohistochemistry (IHC) findings were used as reference standards to evaluate diagnostic performance of cytopathology. Clinical, clinicopathologic, and imaging data also were considered in the definitive diagnosis. Results: Classification accuracy for lymphoma consistently was >80% for all examiners, whereas it was >60% for low grade T-cell lymphomas, >30% for high grade B-cell lymphomas, >20% for high grade T-cell lymphomas, and <40% for low grade B-cell lymphomas. Interobserver agreement evaluated by kappa scores was 0.55 and 0.32 for identification of lymphoma cases, and of grade plus immunophenotype, respectively. Conclusions and Clinical Importance: Cytopathology may result in accurate diagnosis of lymphoma, but accuracy decreases when further characterization is needed. Cytopathology represents a fundamental aid in identifying lymphoma and can be used as a screening test to predict grade and phenotype. However, these results must be confirmed using other ancillary techniques, including flow cytometry, histopathology, and immunohistochemistry (IHC)

Splenic marginal zone lymphoma in 5 dogs (2001-2008)

Background: Splenic marginal zone lymphomas (MZL) in dogs arise from the marginal zone of B-cell follicles and can progress slowly.Objectives: To describe clinical features, treatment, and outcome of dogs with splenic MZL.Animals: Five dogs with naturally occurring MZL.Methods: Clinical, laboratory, and follow-up data were retrospectively reviewed. Diagnosis was based on clinical, histopathological, and immunophenotypic features.Results: All dogs had stage IV disease; among them, 2 were symptomatic (substage "b") because of splenic rupture. Four dogs underwent splenectomy and adjuvant doxorubicin, and 1 dog underwent surgery only. Three out of the 4 dogs treated with surgery and chemotherapy died of causes unrelated to lymphoma, after 760, 939, and 1,825 days, whereas the remaining dog was alive and in complete remission after 445 days. The dog not receiving any adjuvant treatment had recurrence of the tumor after 180 days.Conclusions and Clinical Importance: Splenic MZL appears indolent and can benefit from splenectomy, with or without systemic chemotherapy

Neoplastic diseases in the domestic ferret (Mustela putorius furo) in Italy : classification and tissue distribution of 856 cases (2000-2010)

Background: The aim of this study was to describe the prevalence and tissue distribution of neoplasms in Italian ferrets, compared to the epidemiological data previously reported in USA and Japan. Methods: Signalment and diagnoses of pathological submissions received between 2000 and 2010 were searched; cases with the diagnosis of neoplasm were selected and original sections reviewed to confirm the diagnosis. Results: Nine-hundred and ten samples were retrieved, 690 of which included at least one tumour for a total of 856 tumours. Ferrets with multiple neoplasms were 134 (19.4%). Median age was 5years, and F/M ratio was 0.99. Endocrine neoplasms were the most common. Other frequent tumours were cutaneous mast cell tumours, sebaceous tumours, and lymphomas. Cutaneous squamous cell carcinomas (SCC) were consistently associated with sebaceous tumours. Twenty-four abdominal spindle cell tumours with an undefined origin were observed. Lymphomas and islet cell tumours had a lower incidence compared with previous extra-European studies. Discussion: Epidemiological information on ferret tumours derives from extra-European countries, mostly USA and Japan. In these countries similar distributions with minor discrepancies have been reported. Compared to previous reports, adrenal tumours were more frequent than pancreatic islet cell neoplasms, and a higher number of mesenchymal neoplasms arising from the adrenal capsule was noted. An unusual association between SCC and sebaceous gland neoplasms and a high number of intrabdominal spindle cell neoplasms with unclear primary origin were noted and grants further investigation. Conclusions: The tissue distribution of tumours recorded in this study paralleled previous findings in ferrets from USA and Japan. Some differences have been noted in the frequency of lymphoma, adrenal mesenchymal tumours and cutaneous tumours. Some tumours that are among the most common in other species seem to be uncommon in ferrets and are characterized by distinctive predilection sites

International Guidelines for Veterinary Tumor Pathology: A Call to Action

Standardization of tumor assessment lays the foundation for validation of grading systems, permits reproducibility of oncologic studies among investigators, and increases confidence in the significance of study results. Currently, there is minimal methodological standardization for assessing tumors in veterinary medicine, with few attempts to validate published protocols and grading schemes. The current article attempts to address these shortcomings by providing standard guidelines for tumor assessment parameters and protocols for evaluating specific tumor types. More detailed information is available in the Supplemental Files, the intention of which is 2-fold: publication as part of this commentary, but more importantly, these will be available as “living documents” on a website (www.vetcancerprotocols.org), which will be updated as new information is presented in the peer-reviewed literature. Our hope is that veterinary pathologists will agree that this initiative is needed, and will contribute to and utilize this information for routine diagnostic work and oncologic studies. Journal editors and reviewers can utilize checklists to ensure publications include sufficient detail and standardized methods of tumor assessment. To maintain the relevance of the guidelines and protocols, it is critical that the information is periodically updated and revised as new studies are published and validated with the intent of providing a repository of this information. Our hope is that this initiative (a continuation of efforts published in this journal in 2011) will facilitate collaboration and reproducibility between pathologists and institutions, increase case numbers, and strengthen clinical research findings, thus ensuring continued progress in veterinary oncologic pathology and improving patient care

Feline low-grade alimentary lymphoma: an emerging entity and a potential animal model for human disease

Background: Low-grade alimentary lymphoma (LGAL) is characterised by the infiltration of neoplastic T-lymphocytes, typically in the small intestine. The incidence of LGAL has increased over the last ten years and it is now the most frequent digestive neoplasia in cats and comprises 60 to 75% of gastrointestinal lymphoma cases. Given that LGAL shares common clinical, paraclinical and ultrasonographic features with inflammatory bowel diseases, establishing a diagnosis is challenging. A review was designed to summarise current knowledge of the pathogenesis, diagnosis, prognosis and treatment of feline LGAL. Electronic searches of PubMed and Science Direct were carried out without date or language restrictions. Results: A total of 176 peer-reviewed documents were identified and most of which were published in the last twenty years. 130 studies were found from the veterinary literature and 46 from the human medicine literature. Heterogeneity of study designs and outcome measures made meta-analysis inappropriate. The pathophysiology of feline LGAL still needs to be elucidated, not least the putative roles of infectious agents, environmental factors as well as genetic events. The most common therapeutic strategy is combination treatment with prednisolone and chlorambucil, and prolonged remission can often be achieved. Developments in immunohistochemical analysis and clonality testing have improved the confidence of clinicians in obtaining a correct diagnosis between LGAL and IBD. The condition shares similarities with some diseases in humans, especially human indolent T-cell lymphoproliferative disorder of the gastrointestinal tract. Conclusions: The pathophysiology of feline LGAL still needs to be elucidated and prospective studies as well as standardisation of therapeutic strategies are needed. A combination of conventional histopathology and immunohistochemistry remains the current gold-standard test, but clinicians should be cautious about reclassifying cats previously diagnosed with IBD to lymphoma on the basis of clonality testing. Importantly, feline LGAL could be considered to be a potential animal model for indolent digestive T-cell lymphoproliferative disorder, a rare condition in human medicine

Plane strain bifurcations of elastic layered structures subject to finite bending: theory versus experiments

Finite plane strain bending is solved for a multilayered elastic–incompressible thick plate. This multilayered solution, previously considered only in the case of homogeneity, is in itself interesting and reveals complex stress states such as the existence of more than one neutral axis for certain geometries. The bending solution is employed to investigate possible incremental bifurcations. The analysis reveals that a multilayered structure can behave in a completely different way from the corresponding homogeneous plate. For a thick plate of neo-Hookean material, for instance, the presence of a stiff coating strongly affects the bifurcation critical angle. Experiments designed and performed to substantiate our theoretical findings demonstrate that the theory can be effectively used as a design tool for predicting the capability of an elastic multilayered structure to be subject to a finite bending without suffering localized crazing

Anatomical evaluation of soft palate in adult and neonate brachycephalic dogs: morphological features at the basis of brachycephalic airway obstructive syndrome

Introduction: Increased length of soft palate is one of the main factors contributing to pharyngeal narrowing during respiratory activity in brachycephalic dogs. However, no histological studies assessing soft palate morphology and normal tissue composition in brachycephalic breeds are available. The aim of this study was to compare soft palate morphology in brachycephalic versus mesocephalic dogs in order to identify potential anatomical differences involved in the pathogenesis of the brachycephalic airway obstructive syndrome (BAOS), a disease which very frequently affects these breeds during their postnatal life. The soft palate of brachycephalic neonates was also examined to evaluate its morphology at birth. Methods: Specimens from brachycephalic dogs (N=11) with long soft palate and from mesocephalic dogs (N=8) were collected at surgery and euthanasia respectively, processed for histology and examined at six transversal levels. The soft palate dissected from brachycephalic neonates (N=10) dying spontaneously at birth of unrelated conditions was examined as well. Results: Compared with mesocephalic soft palates, brachycephalic samples showed progressive, quali-quantitative changes, such as thickened superficial epithelium, extensive increase of interfibrillar matrix, oedema of the lamina propria and mucous gland hyperplasia. Muscular degenerative changes were evidenced. In the soft palate of neonate brachycephalic dogs lesions were absent. Conclusions: The results of this investigation add further insights into the anatomy of soft palate in the canine species and identify key morphological features at the basis of soft palate thickening in brachycephalic dogs. Functional impairment of soft palate associated with BAOS is morphologically justified by oedema, increased intercellular myxoid matrix as well as increased mucin production by the hyperplastic glands. Based on these findings, a likely hypothesis is that the dysfunctional inspiratory efforts induce chronic vibration and microtrauma that cause the soft palate changes identified in brachycephalic dogs. This hypothesis is further substantiated by absence of tissue lesions in newborn brachycephalic dogs

A multiple endocrine neoplasia type 1-like syndrome in a cat

A 15 years short hair male cat was referred to our clinic for a poorly controlled diabetes mellitus which had been diagnosed 3 years before. The cat presented polyuria and polydipsia, weight loss and poor haircoat. Three seizures episodes were described in the last two months. Cutaneous changes were represented by extensive alopecia thin, fragile and easily wrinkled skin with crusted wounds, prominent vasculature and comedones. The hair loss involved the abdomen, the flank region and the proximal part of the extremities. Hyperkeratotic paws were present. These dermatologic findings had been developed in the last six months. Hyperglycemia, hyperlipaemia, high levels of serum ALT and fructosamine were the most evident biochemical evidences. Abdomen ultrasonography showed hepatomegaly with focal hypoechoic parenchimal lesions, enlarged gallbladder, extrahepatic bile ducts distensions. These findings suggested an hepatic neoplasia and a pancreatic involvment (extrahepatic bile ducts enlarged). Hypertrophic adrenal glands were also observed. Although not commonly reported, the Cushing\u2019s Syndrome in the cat is usually described with concurrent diabetes mellitus. In order to provide that, we performed a high-dose dexamethasone suppression test. The suppression by more than 50% below baseline value following administration of a high dose of DXM suggested a pituitary dependent hyperadrenocorticism (PDH). However the owner refused any further therapy rather than insulin. The cat was euthanisized a month later. The post mortem examination showed: a pituitary basophil adenocarcinoma, a pancreatic islet cells adenocarcinoma and an hepatic carcinoma suggesting a multiple endocrine neoplasia. Adrenal cortex hyperplasia, cutaneous follicular and dermal atrophy was also assessed as the consequences of the Cushing\u2019s Syndrome. In human, several combination of endocrine tumours are known to occur. They are refferred to as multiple endocrine neoplasias (MEN) and are related to a common gene defect, including inactivation of both alleles of a tumour suppressor gene. MEN 1 subgroup includes combinations of parathyroid and pituitary hyperplasia and/or neoplasia and pancreatic islet cells neoplasia. MEN syndromes are rare in veterinary medicine and mostly described in the dog. The case reported was clinically diagnosed as a Cushing\u2019s Syndrome. Only the post-mortem examination could identify the multiple endocrine glands involvment and diagnose a MEN 1-like syndrome. Further studies are needed to identify a genetic defect such as described in human pathology