Veterinary Pathology最新文献

Sarcoma samples from 33 dogs, 25 subcutaneous and 8 articular, were submitted for cytokeratin immunohistochemistry. Eight of the 25 subcutaneous sarcomas (32%) expressed cytokeratin in 1% to 50% of the neoplastic cells. Of the 7 articular sarcomas evaluated, 1 (14%) expressed cytokeratin in 10% of neoplastic cells. The Kaplan-Meier survival analysis showed that the mean overall survival of dogs with subcutaneous sarcomas (28.1 months [confidence interval [CI]:17.8, 38.4]) did not significantly differ from those with articular sarcomas (24.8 months [CI = 0.5, 29.0]). Overall survival of dogs with sarcomas (both locations combined) immunoreactive for cytokeratin (31.2 months [CI = 17.8, 44.6]) did not differ from those not immunoreactive for cytokeratin (22.0 months [CI = 8.4, 35.6]). Therefore, cytokeratin expression does not indicate synovial origin (P = .64) and neither sarcoma location (P = .76) nor cytokeratin expression (P = .53) affects patient overall survival in this small study. The use of cytokeratin immunohistochemistry is not helpful to determine synovial origin of sarcomas in dogs.

Splenic rupture in cattle is scarcely described in the literature. The aim of this work was to report the occurrence of splenic rupture in cattle in southern Brazil as well as to describe the causes of the condition. Between 2013 and 2022, 24 of the 1769 bovine necropsies performed in southern Brazil were due to splenic rupture, accounting for 1.36% of the diagnoses. Animals died due to hemoperitoneum caused by a rupture in the splenic capsule, typically associated with marked splenomegaly and a large hematoma between the capsule and the parenchyma. Clinical signs were described in a subset of cases (11 of 24 cases, 46%) and included apathy, abdominal pain, mucosal pallor, tachycardia, and respiratory distress. However, the majority (13 of 24 cases, 54%) presented as sudden death. The underlying cause of splenic rupture was established as follows: 16 cases (67%) secondary to babesiosis, 4 cases (17%) due to lymphoma, 1 case (4%) due to a thrombus, 1 case (4%) due to external trauma, 1 case due to a ruptured nodular lymphoid hyperplasia (4%), and 1 case of undetermined cause (4%). Hypovolemic shock caused by splenic rupture is an important cause of death of dairy cattle, and babesiosis and bovine leukemia virus-associated lymphoma are among the most common etiologic diagnoses (84% of cases). The description of the causes of this condition is important to clarify the pathogenesis and occurrence of splenic rupture in dairy cattle.

Tumors in boars are uncommon, and testicular tumors even rarer. This study describes the pathological and immunohistochemical characteristics of a case series of testicular tumors in commercial boars with fertility problems. Tumors were detected in 19 of 333 animals (19/333, 5.9%). Macroscopically, tumors were observed in 13 (13/19, 68%) boars, while 6 cases (6/19, 32%) were only detected by microscopic examination. Testicular enlargement was observed in 1 boar, while in the others, tumors were only observed after removal of the scrotal skin or after sectioning of the testis. Histologically, tumors were classified as seminomas (16/19, 84%), mixed germ cell-stromal tumors (2/19, 11%), and B-cell lymphoma (1/19, 5%). Seminomas had 3 different growth patterns: intratubular (6/16, 38%), diffuse (4/16, 25%), and intratubular/diffuse (6/16, 38%). All tumors that were not evident on macroscopic examination were intratubular seminomas. Intratesticular metastases were observed in 2 cases and extratesticular metastases, located in the pampiniform plexus, were observed in 1 case. In 1 seminoma, the rete testis was also involved. By immunohistochemistry, all intratubular seminomas were negative for c-kit, cytokeratin, and vimentin. In diffuse seminomas, c-kit and cytokeratin were also negative, while vimentin showed granular or perinuclear cytoplasmic labeling in some areas. PAX-5 and CD-3 antibodies classified the lymphoma as a B-cell lymphoma. This study suggests that testicular tumors in boars may be more common than previously reported, especially when microscopic examination is performed. It also shows that testicular tumors in pigs are predominantly seminomas.

Epithelioid hemangiosarcoma (EH), a rare histological variant of hemangiosarcoma, is reported in various animal species, including humans, dogs, cows, horses, and cats. Epithelioid hemangiosarcomas are composed of highly pleomorphic epithelioid cells arranged in cords, islands, nests, or solid cellular areas, similar to epithelial neoplasms. Moreover, in humans, approximately 50% of EHs have cytoplasmic immunolabeling for cytokeratin AE1/AE3 (CK AE1/AE3), making it challenging to distinguish them from carcinomas. This retrospective study assessed the CK AE1/AE3 immunolabeling in canine EH cases from 5 veterinary institutions. Immunohistochemistry for CD31 and CK AE1/AE3 was performed on 30 cases. CK AE1/AE3 immunolabeling was detected in 43% (13/30) of cases, with cytoplasmic labeling ranging from 5% to 100% of neoplastic cells. All tumors consistently had membranous immunolabeling for CD31. The CK AE1/AE3 immunolabeling pattern in canine EHs closely resembled those documented in humans, indicating a similar diagnostic challenge. Therefore, it is recommended to include a vascular immunohistochemistry marker, such as CD31, whenever EH is suspected, particularly in small incisional cutaneous and subcutaneous biopsies.

Fibrolipoma is defined as a typical lipoma transected by variable amounts of paucicellular and collagenous fibrous components. Oral and lingual fibrolipomas are well-recognized histological entities in human medicine that are slightly more prevalent in females, occur most commonly after the fourth decade, and arise from the buccal mucosa. The documentation of this neoplasm in the oral cavity is lacking in veterinary medicine. Through a multi-institutional retrospective compilation of cases submitted to diagnostic pathology services, here we describe the clinical and pathologic features of oral fibrolipomas in dogs. A total of 112 cases of oral fibrolipomas in dogs were retrieved. The mean age was 10.1 years (range 2-16 years, ±2.63 years standard deviation), with an average tumor size of 1.7 cm (range 0.2-8 cm, ±1.1 cm standard deviation). The most common location was the tongue (57.1%, 64/112), followed by the buccal mucosa (15.2%, 16/112), sublingual area (8.0%, 9/112), gingiva and lip (4.5%, 5/112 each), and palate (1 case). The anatomical location of oral fibrolipomas only differed significantly among the dog breeds (P < .001) but not among sex, age, anamnesis, or reason for submission. The tumor was most commonly reported in males (69.7%, 78/112), and in 62.5% (70/112) of the cases, the tumor was an incidental finding. Fibrolipoma should be considered a differential diagnosis when considering benign lingual and other oral soft tissue masses in dogs.

Large-scale retrospective studies allow for identification of disease trends, such as predisposing factors, typical clinical signs, and range of histologic lesions, which cannot be determined in individual case reports. Lesions of the endocrine pancreas of ferrets are extensively reported; however, there are no in-depth investigations of lesions in the exocrine pancreas. This retrospective analysis presents the histologic features, clinical signs, and concurrent diseases of lesions in the exocrine pancreas of ferrets. Seventy-seven lesions were reported and included acinar cell hyperplasia (n = 32), chronic pancreatitis (n = 16), acute pancreatitis (n = 13), acinar cell adenoma (n = 5), acinar cell carcinoma (n = 4), acinar cell atrophy (n = 3), presumptive acinar cell hypoplasia (n = 2), and lymphoma (n = 2). Our results demonstrate that acinar cell hyperplasia and chronic pancreatitis can both cause grossly visible pancreatic nodules. Hyperplasia was not associated with neoplastic transformation. In addition, acinar cell adenoma was slightly more common than carcinoma, which is contrary to most reports of neoplasia in ferrets. Our findings also suggest that acute pancreatitis can be a sequela to pancreatic biopsy and that there may be an association between chronic pancreatitis and diabetes mellitus in ferrets. Finally, zinc toxicosis was found to be an unlikely cause of pancreatitis in these ferrets based on zinc tissue concentration testing in a subset of cases.

A foxhound from a hunting kennel in the United Kingdom was euthanized after being hospitalized with progressive neurologic signs, including tremors, seizures, and obtunded mentation. No abnormalities were appreciated on gross postmortem examination. Histologically, severe meningoencephalomyelitis and mild neuritis of the brachial plexus were present. Molecular analysis of brain tissue detected louping ill virus. In addition, louping ill virus-specific antigens were detected in neurons within the brainstem, the entire length of the spinal cord, as well as in rare cells in the brachial plexus using immunohistochemistry. The genetic sequence of the virus appears most closely related to a previously detected virus in a dog from a similar geographic location in 2015. This is the first characterization of the inflammatory lesions and viral distribution of louping ill virus in a naturally infected dog within the spinal cord and brachial plexus.

The factors that determine the appearance of the different pathologic forms associated with bovine paratuberculosis are not fully understood, but new research suggests a critical role of innate immunity. Toll-like receptors (TLRs) trigger the recognition of invading pathogens by innate immune cells and the onset of specific immune responses. The aim of this work was to assess, immunohistochemically, the expression of TLR1, TLR2, TLR4, and TLR9 in intestinal samples of 20 cows showing different types of paratuberculous lesions: uninfected controls, focal lesions, paucibacillary, and multibacillary diffuse forms. The majority of labeled cells were morphologically consistent with macrophages. A differential cell count was performed in the intestinal lamina propria, gut-associated lymphoid tissue, and mesenteric lymph node. TLR9 immunolabeling between the different types of lesions was compared using a complete H-score. Focal and diffuse paucibacillary forms contained significantly increased TLR2-expressing macrophages outside of the lesions compared with the controls and diffuse multibacillary forms, and moderate TLR9 immunolabeling within granulomas. In the multibacillary granulomatous lesions, the expression of TLR1 and TLR4 was observed as well as increased TLR9 expression compared with the rest of the groups. Differences in the predominance of one type or another of TLR allows us to elucidate the importance of the innate immune response and its possible role in the development of the different types of paratuberculosis lesions.