Magnetic Resonance Imaging and Clinical Findings Associated with Choroid Plexus Spinal Cord "Drop" Metastases.

A 5 yr old castrated male whippet presented with a unique presentation of ambulatory paraparesis and subsequent diagnosis of primary intracranial choroid plexus carcinoma, with metastases to the cervical, thoracic, lumbar, and sacral spinal cord segments. Magnetic resonance imaging was performed initially of the thoracolumbar vertebral column and was followed by MRI sequences of the brain for confirmation of the presence of a primary intracranial tumor. The dog was euthanized immediately following diagnostic imaging due to the severity of clinical signs and poor prognosis. Postmortem examination confirmed the presence of a primary choroid plexus carcinoma, with diffuse metastatic lesions to the spinal cord. To the authors' knowledge, this is the first description of MRI findings of spinal cord metastasis of a choroid plexus carcinoma in a dog. Additionally, this case demonstrates primary clinical signs arising from metastatic lesions. This confirms the importance of extensive neuroimaging investigations when suspecting choroid plexus tumors and evaluating response to treatment regimens.

Evaluation of a modified proportional margins approach for surgical resection of mast cell tumors in dogs: 40 cases (2008-2012).

OBJECTIVE: To evaluate a modified proportional margins approach to resection of mast cell tumors (MCTs) in dogs. DESIGN: Retrospective case series. ANIMALS: 40 dogs with subcutaneous and cutaneous MCTs undergoing curative intent surgery. PROCEDURES: Medical records were searched to identify dogs with a cytologically or histologically confirmed diagnosis of MCT that had not previously been treated surgically and that had undergone full oncological staging. In those dogs, tumors were resected with lateral margins equivalent to the widest measured diameter of the tumor and a minimum depth of 1 well-defined fascial plane deep to the tumor. Surgical margins were evaluated histologically. Cutaneous tumors were graded by use of the Patnaik system and the 2-tier system described by Kiupel et al. The prognosis for subcutaneous tumors was assessed in accordance with published recommendations. Follow-up information on dog health status was obtained through clinical examination, the dog owners, and the referring veterinarians. RESULTS: The 40 dogs had 47 tumors. Forty-one (87%) tumors were cutaneous, and 6 (13%) were subcutaneous. On the basis of the Patnaik system, 21 (51%) cutaneous tumors were considered grade I, 18 (44%) were considered grade II, and 2 (5%) were considered grade III. On the basis of the Kiupel system, 37 (90%) cutaneous tumors were considered low grade, and 4 (10%) were considered high grade. The prognosis for the 6 subcutaneous tumors was classified as likely resulting in a shorter (2) or longer (4) survival time. Forty tumors were deemed to have been excised with clear margins and 7 with incomplete margins. Local recurrence was not recorded for any dog but was suspected for 1 (2%) tumor, although not confirmed. Interval from tumor excision to follow-up ranged from 30 to 1,140 days (median, 420 days). CONCLUSIONS AND CLINICAL RELEVANCE: The modified proportional margins system resulted in satisfactory local disease control in dogs with MCTs.

Granulomatous rhinitis due to Candida parapsilosis in a cat.

A 9-year-old female spayed Domestic Medium Hair cat presented to the referring veterinarian with a 2-week history of sneezing, which progressed to swelling over the nasal planum. The cat had been under veterinary care for inflammatory bowel disease and had been treated with 1.25 mg/kg prednisolone once a day for approximately 1 year. On physical examination, an approximately 2-3 mm diameter, round polypoid pink soft-tissue mass was protruding slightly from the right nostril. Through histologic examination of representative sections from the mass, there was a severe diffuse infiltrate of epithelioid macrophages and neutrophils that surrounded frequent 15-20 µm yeast organisms. A Grocott methenamine silver stain revealed the presence of pseudohyphae in addition to the previously noted yeast forms. Real-time polymerase chain reaction (PCR) for Cryptococcus neoformans, Ajellomyces dermatitidis (syn. Blastomyces dermatitidis), Coccidioides immitis, Ajellomyces capsulatus (syn. Histoplasma capsulatum), Malassezia spp., and Candida spp. was performed on the paraffin-embedded sample. The PCR for Candida spp. was positive; the product was then sequenced and was determined to be consistent with Candida parapsilosis. Following the PCR diagnosis and prior to treatment of the infection, C. parapsilosis was cultured from a nasal swab. The infection in the cat in the current report was considered opportunistic and secondary to immunosuppression, following treatment for the inflammatory bowel disease.

Intracoelomic anaplastic sarcoma in an intersex Madagascar tree boa (Sanzinia madagascariensis).

An adult Madagascar tree boa (Sanzinia madagascariensis) underwent coeliotomy for investigation of a coelomic mass. At surgery, a large mass originating from the peri-pancreatic adipose tissue and involving the gall bladder was removed. The snake did not recover from general anesthesia. A complete postmortem was performed, and samples were submitted to the University of Glasgow for histopathology. On histological examination, the mass was composed of adipose tissue infiltrated with a poorly demarcated spindle cell neoplasm. The neoplastic cells were highly pleomorphic with abundant cytoplasm and frequent clear cytoplasmic vacuoles, suggestive of adipocyte origin. Immunohistochemical characterization of the mass was inconclusive. Metastatic neoplastic cells were present within vessels in the liver, lungs, and brain. As an incidental finding, the gonads contained both maturing ovarian follicles and seminiferous tubules with intact germinal epithelium and evidence of spermatogenesis, along with other features of male and female gonad anatomy. The current report describes a rare neoplasm in snakes within an intersex Madagascar tree boa.

Gross lesions of alimentary disease in adult cattle.

The purpose of the gross necropsy examination of the gastrointestinal tract is to recognize the presence of lesions, thus requiring a basic understanding of its normal appearance and anatomy. This article highlights gross changes to the gastrointestinal tract of adult cattle that help place the disease processes into broad categories. Although few gross lesions reach the zenith of pathognomonic, there are numerous lesions that, when considered in aggregate with history (eg, number of animals affected, environment, duration of signs, time of onset relative to management changes, previous management) and clinical signs, can help narrow the spectrum of causes, provide a basis for a strong presumptive diagnosis, and focus diagnostic test selection.

Caudal vena caval thrombosis following treatment of deep digital sepsis.

A diagnosis of caudal vena caval thrombosis was made by ultrasonography of a Holstein cow presented for lethargy and poor milk production. Medical treatment was unsuccessful and the cow was euthanized. The diagnosis was confirmed at necropsy and Fusobacterium necrophorum was isolated from the thrombus. This paper discusses potential novel sources of caval thrombosis in this case.

Activation of Wnt signalling promotes development of dysplasia in Barrett's oesophagus.

Barrett's oesophagus is a precursor of oesophageal adenocarcinoma, via intestinal metaplasia and dysplasia. Risk of cancer increases substantially with dysplasia, particularly high-grade dysplasia. Thus, there is a clinical need to identify and treat patients with early-stage disease (metaplasia and low-grade dysplasia) that are at high risk of cancer. Activated Wnt signalling is critical for normal intestinal development and homeostasis, but less so for oesophageal development. Therefore, we asked whether abnormally increased Wnt signalling contributes to the development of Barrett's oesophagus (intestinal metaplasia) and/or dysplasia. Forty patients with Barrett's metaplasia, dysplasia or adenocarcinoma underwent endoscopy and biopsy. Mice with tamoxifen- and ß-naphthoflavone-induced expression of activated ß-catenin were used to up-regulate Wnt signalling in mouse oesophagus. Immunohistochemistry of ß-catenin, Ki67, a panel of Wnt target genes, and markers of intestinal metaplasia was performed on human and mouse tissues. In human tissues, expression of nuclear activated ß-catenin was found in dysplasia, particularly high grade. Barrett's metaplasia did not show high levels of activated ß-catenin. Up-regulation of Ki67 and Wnt target genes was also mostly associated with high-grade dysplasia. Aberrant activation of Wnt signalling in mouse oesophagus caused marked tissue disorganization with features of dysplasia, but only selected molecular indicators of metaplasia. Based on these results in human tissues and a mouse model, we conclude that abnormal activation of Wnt signalling likely plays only a minor role in initiation of Barrett's metaplasia but a more critical role in progression to dysplasia.

Current advances in gestation and parturition in cats and dogs.

This article provides an overview of pregnancy in the bitch and queen. Emphasis will be placed on pregnancy diagnosis, monitoring pregnancy, and prevention of fetal loss and maternal morbidity.

Clinical approach to abortion, stillbirth, and neonatal death in dogs and cats.

This article reviews post-mortem examination, sample collection, and diagnostic procedures used to determine the cause of abortion, stillbirth, and neonatal death in dogs and cats.

Comparison of antemortem antimicrobial treatment regimens to antimicrobial susceptibility patterns of postmortem lung isolates from feedlot cattle with bronchopneumonia.

A retrospective study was performed to compare the treatment regimens in feedlot cattle that died with bovine respiratory disease (BRD) to the antimicrobial susceptibility patterns of the microorganisms isolated from lungs. Forty-three cattle submitted by the Willard Sparks Beef Research Center (WSBRC) to the Oklahoma Animal Disease Diagnostic Laboratory for postmortem examination during 2007 had bronchopneumonia (acute = 16, subacute = 5, or chronic = 22). Lungs from cattle were cultured aerobically (40 cattle) and for Mycoplasma spp. (34 cattle). Susceptibility panels were performed. At least 1 BRD pathogen (Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, Mycoplasma bovis, or Arcanobacterium pyogenes) was isolated from 39 cattle, and 77% (30/39) had multiple organisms recovered. Mycoplasmal infections were common (25/34) and a major component of mixed infections (24/25). The majority (60%) of the M. haemolytica, P. multocida, and H. somni isolates were resistant to tetracycline. Most of the H. somni isolates (67%) were susceptible to tilmicosin (Ti), enrofloxacin (En), ceftiofur (Ce), and florfenicol, despite extensive treatment with Ti, En, and Ce (75% of isolates were from cattle that received each antimicrobial once). Most of the M. haemolytica (65%) and P. multocida (79%) isolates were susceptible to En and Ce, despite antemortem treatment of cattle with these antimicrobials. Hence, the current study reports a discrepancy between the antemortem treatment of clinical BRD and the susceptibility patterns of the bacteria isolated from lungs postmortem. Based on these findings, factors other than antimicrobial resistance are playing a role in the death of feedlot cattle with BRD.

Utilization of paw prints for species identification in the Canidae family.

In this report, the bodies of six skinned animals were submitted to the Oklahoma Animal Disease Diagnostic Laboratory for necropsy examination as authorities were concerned these animals were domestic dogs. Given the condition of the animals, identification of the animal species could not be based on traditional physical characteristics such as size, fur characteristics, and ear characteristics. The paw prints from these animals were characterized based on size, heel pad architecture, and claw characteristics. The length of the forepaws measured 3-3.25 in., four toes were observed and only the claws of digits 3 and 4 were identified, and the heel pad had a pronounced three-lobed rear margin. The rear margin of the heel pad of the hind foot was of circular shape with two slightly forward-pointing crescents laterally. Based on the features of the paw print it was determined that the animals necropsied were coyotes.

Feline intracranial meningioma with skull erosion and tumour extension into an area of skull hyperostosis.

Skull hyperostosis is a frequently recognised feature of meningioma in feline and human patients, occurring at a frequency of around 4.5% of human cases. Evidence of osteolysis with extension of meningioma into, and in some cases through, the region of skull hyperostosis is much less commonly described in human patients. Here we present a 12-year-old cat with marked skull hyperostosis secondary to an intracranial meningioma, with magnetic resonance imaging and computed tomography evidence of tumour extension into the skull, centrally within the region of hyperostosis. Only a thin layer of bone was remaining between the mass and the extracranial region. Surgical resection of the region of skull demonstrating tumour invasion and the underlying mass resulted in good resolution of clinical signs and no post-surgical recurrence of meningioma within the 5 months follow-up period. Histopathological examination confirmed the mass to be fibroblastic meningioma.