Veterinary Pathology最新文献

This report describes a series of ethmoid tumors in 6, free-ranging white-tailed deer (Odocoileus virginianus; WTD) in southwest to central Texas, which included 4 plasma cell tumors, 1 adenosquamous carcinoma, and 1 adenocarcinoma. The plasma cell tumors had a distinctive presentation with unilateral to bilateral facial masses located rostromedial to the eyes that were smooth and fluctuant. Upon dissection, these preorbital facial masses consisted of multiloculated, mucus-filled, cystic pockets with 2 having partial extension of the ethmoid tumors into the external facial masses. The 2 carcinomas were larger, unilateral, solid facial masses. All tumors caused extensive destruction of the ethmoid region with the carcinomas being paler, firmer, and more invasive into surrounding areas compared with the plasma cell tumors. Ancillary testing did not reveal an underlying infectious cause, although these reports of multiple WTD across a localized region suggest a possible infectious, environmental, or other shared stimulus.

Iron overload is a leading cause of morbidity and mortality in Egyptian rousette bats (ERBs; Rousettus aegyptiacus) within managed care settings. We compared hepatic iron accumulation and tissue damage in samples collected from managed care bats in a zoo setting, a research colony, and a free-ranging population with the goal of determining if iron overload was a potential cause of morbidity for free-ranging ERBs. Livers from 20 zoo bats, 8 research colony bats, and 69 free-ranging bats were histologically evaluated for fibrosis, necrosis, and iron accumulation in hepatocytes and Kupffer cells. Hemochromatosis was identified only in the zoo population, with hemosiderosis identified in all research colony bats and many free-ranging bats. There were statistically significant associations between age classification, population, and diagnosis and between Marburg virus infection status and histologic liver iron scores. In addition, there were positive associations with statistical significance between age class (juvenile, adult) and histologic iron scores and between population type (zoo bats > research colony bats > free-ranging bats) and histologic iron scores. Excessive hepatic iron storage does not appear to be a source of morbidity within free-ranging ERB populations.

A high mortality event occurred among Malabar groupers (Epinephelus malabaricus) reared for research. The affected fish had scattered reddish patches and ulcers on the skin, accompanied by parasite infestations on the skin surface. Histologic findings included ulcerative dermatitis and keratoconjunctivitis with gram-negative bacilli, and the parasites were often observed on the skin surface. Bacterial examinations and in situ hybridization revealed the presence of Vibrio harveyi in the affected tissues. The parasites were morphologically identified as the subfamily Benedeniinae (Monogenea: Capsalidae), likely Neobenedenia girellae. The monogeneans may have come into contact with the fish at a farm in Okinawa, Japan, and potentially facilitated the opportunistic infection with V. harveyi. This is the first report of vibriosis caused by V. harveyi in Malabar groupers.

Injections have been linked to feline sarcomas (feline injection-site sarcoma; FISS) and cutaneous lymphomas (cutaneous lymphoma at injection site; CLIS). Both tumors often exhibit lymphoplasmacytic inflammation ascribed to injected immunogenic material. CLIS is hypothesized to emerge from transformation and clonal expansion of lymphoid cells following persistent immune stimulation with feline leukemia virus (FeLV) reactivation and transformation. To further study whether the lymphocytic infiltrates associated with FISS can represent a suitable niche for the development of CLIS, 34 cases of FISS were examined. Lymphoid cell phenotypes were assessed using CD3 and CD79 immunohistochemistry. For cases with prominent inflammation, FeLV p27 and gp70 immunohistochemistry and PCR for antigen receptor rearrangements were performed. Male domestic shorthair cats predominated. The mean age was 12.2 years (range: 5-17 years). FISS developed in thoracic (8/34, 24%), flank (7/34, 21%), and interscapular (5/34, 15%) regions. Similar proportions of B and T lymphocytes were found in 11/34 (32%) cases; T-cells predominated in 12/34 (35%) cases, and B-cells predominated in 11/34 (32%). At least one FeLV antigen was expressed in lymphoid infiltrates in 10/18 cases (55%), and in neoplastic fibroblasts in 8/18 cases (44%), while both FeLV proteins were expressed in neoplastic cells in 3/18 cases (17%). One cat had clonal T-cell receptor-gamma and was diagnosed with concurrent FISS and CLIS. This case lacked FeLV expression. FeLV amplification from formalin-fixed paraffin-embedded material was unsuccessful. The expression of FeLV p27 and/or gp70 in neoplastic spindle cells and lymphoid infiltrates raises the possibility of FeLV involvement in the tumorigenesis of FISS and CLISs.

Herpesviruses are among the most significant viral pathogens that affect captive and free-ranging testudines. Moreover, herpesviruses are known to establish latent infections. In this report, we describe 2 cases of Trachemys herpesvirus infection in captive adult black-bellied sliders (Trachemys dorbigni) submitted for necropsy after a 2-week history of respiratory signs and oral lesions. Gross examination revealed severe diphtheric stomatitis, rhinitis, tracheitis, esophagitis, gastritis, and reddened lungs. Histologically, there were multifocal areas of necrosis with syncytial cells and fibrin deposition. Intranuclear amphophilic to eosinophilic inclusions were frequent in epithelial and syncytial cells, especially in the respiratory tract. Oral cavity and esophageal swabs were collected during necropsy and subjected to a multiplex nested PCR assay targeting herpesvirus DNA. The amplified DNA was sequenced and analyzed phylogenetically, confirming the virus as Trachemys herpesvirus. This is the first detailed description of clinical disease and associated lesions caused by Trachemys herpesvirus infection.

Avian reovirus (ARV), the etiologic agent of poultry viral arthritis/tenosynovitis, frequently presents diagnostic challenges due to its non-specific lesions, ubiquitous nature, and the lack of standardized diagnostic guidelines. We describe cases of poultry arthritis/tenosynovitis, where ARV was the suspected etiology, and investigate the relationship between lesion severity and viral RNA levels using quantitative real-time reverse-transcriptase polymerase chain reaction (qRT-PCR) with RNAScope in situ hybridization (ISH) to support ARV detection and analysis. A total of 51 cases (qRT-PCR positive [n = 38; Ct range = 20.9-35.9] and qRT-PCR negative [n = 13; Ct > 37]) were analyzed, with case selection criteria including clinical lameness, complete histologic examination of the gastrocnemius/digital flexor tendons, and qRT-PCR testing for ARV. A subset of qRT-PCR positive cases (n = 33) and negative cases (n = 8) with the sections showing the most severe histologic lesions were selected for ISH. Histologic scoring of tenosynovitis included inflammation severity; synovial proliferation; and the presence of lymphoid nodules, neovascularization, and fibrosis. The qRT-PCR positive cases had significantly higher histologic scores than negative cases. The ISH detected viral transcripts within synoviocytes and subintimal fibroblasts only in qRT-PCR positive cases (11/33, 33.3%; Ct range = 20.9-32.3). Positive ISH results were also statistically associated with lower Ct values and higher lesion scores. In conclusion, this study aids in ARV diagnostic challenges by linking lesion severity with viral transcription, identifying fibroblasts as ARV-infected cells, and demonstrating ISH as both a valuable diagnostic tool and a means to studying ARV pathogenesis in poultry.

Canine appendicular osteosarcoma (OSA) is a highly metastatic tumor in dogs. Mortality due to metastatic disease is common and frequently occurs within 1 year of diagnosis despite standard-of-care treatment. Treatment includes amputation for palliation and chemotherapy for metastatic disease. Current histologic grading schemes and biomarkers are poor at predicting clinical outcome. Novel prognostic and therapeutic markers are required to improve patient care. MicroRNAs (miRNAs) are small molecules expressed by all cells and released into bodily fluids. Studies in human and canine OSA cell lines, tissues from the primary site, and blood have demonstrated the role of miRNAs in metastatic progression of OSA and its prognostication. We sought to investigate the miRNA profile of primary OSA tissue and compare it to pulmonary metastases and normal lung tissue by real-time quantitative polymerase chain reaction (PCR). Multiple miRNA and multiple variable models were investigated in primary OSA tissue to predict clinical outcome. Thirteen miRNAs had similar expression between primary and metastatic OSA but were different from normal lung tissue. MiR-9-5p, miR-196a-5p, and miR-196b were expressed in metastatic OSA but lacked expression in almost all normal lung samples. In multiple variable models for overall survival and disease-free interval, only miRNAs were selected as significant variables. This study found miRNAs that are nearly exclusively expressed in metastatic pulmonary OSA and could serve as novel therapeutic targets. MiRNAs were also found to be important prognostic biomarkers in tissue and improved prognostic ability as miRNA signatures.

Lymphocryptoviruses (LCVs), members of the Gammaherpesvirinae subfamily, are associated with chronic fibrotic diseases in humans and animals. This study investigated LCV infection in 7 orangutans (Pongo pygmaeus), including 2 recent cases with severe respiratory disease and 5 archival cases analyzed retrospectively. Comprehensive necropsies were conducted on the recent cases, and all 7 underwent histopathological evaluation, quantitative polymerase chain reaction (qPCR), and in situ hybridization (ISH). LCV was detected in 3 cases (43%) by qPCR, including the 2 recent cases and 1 archival case. The highest viral loads, as determined by the qPCR, were observed in the lungs of positive cases. Histological examination revealed significant pulmonary interstitial fibrosis and vascular remodeling in all LCV-positive cases, and type II pneumocyte hypertrophy was most prominent in an acute case. Masson's trichrome staining confirmed varying degrees of fibrosis in the pulmonary interstitium and perivascular stroma. LCV DNA, identified through ISH, was observed in alveolar macrophages, endothelial cells of pulmonary capillaries, and spindle cells within fibrotic regions of the lung and heart. Viral isolation from lung tissue in 1 recent case was successful, demonstrating cytopathic effects in Vero cells. Genetic sequencing revealed a novel LCV strain closely related to Pongo pygmaeus lymphocryptovirus-1 and Macacine lymphocryptoviruses. These findings link LCV infection to fibrotic pulmonary lesions in orangutans. Further studies are essential to elucidate the mechanisms of LCV-related disease and its implications for wildlife conservation.