Imaging diagnosis--Conventional and functional magnetic resonance imaging of a brain abscess in a goat.

A 2-month-old female goat was presented for depressed mental status and multifocal central neurologic signs 3 weeks after hot-iron disbudding. Conventional magnetic resonance imaging (MRI) findings included a large intra axial mass in the left frontal lobe that was T2 hyperintense and T1 hypointense centrally with a contrast-enhancing peripheral capsule and perilesional T2 hyperintensity. A restrictive pattern was present in diffusion-weighted imaging. Magnetic resonance spectroscopy demonstrated an increased amount of succinate, acetate, amino acids, lipids; minimal amounts of lactate; and decreased amounts of N-acetyl aspartate and choline. A cerebral abscess due to Trueperella pyogenes was confirmed from necropsy and tissue culture.

Generalized Taenia crassiceps cysticercosis in a chinchilla (Chinchilla lanigera).

Taenia crassiceps is a cestode parasite that uses carnivores as definitive hosts and rodents and rabbits as main intermediate hosts, but other animal species and humans may also get infected. One adult male chinchilla (Chinchilla lanigera) from an animal shelter in Switzerland presented widespread subcutaneous fluctuant swellings extended over the forehead, nose, face and thoracic regions with a progressive growth over 3 months. The thoracic swelling was surgically resected, and it consisted of numerous 3-4mm small transparent vesicles, mainly confined to the subcutaneous tissue, which were morphologically identified as cysticerci of T. crassiceps. The diagnosis was confirmed by PCR and DNA sequence analysis of fragments of the mitochondrial small subunit rRNA and NADH dehydrogenase subunit 1 genes. After 1.5 months, due to enlargement of the swollen areas and deterioration of the general health condition, the chinchilla was euthanized and a necropsy was performed. Thousands of small cysticerci were observed widespread in the subcutis, involving underlying musculature of the whole body, in the thoracic cavity, larynx, pharynx and in the retropharyngeal region. Additionally, three larger metacestodes were detected in the liver and morphologically and molecularly identified as Taenia taeniaeformis strobilocerci. The present case represents an indicator of the environmental contamination with Taenia eggs, highlighting the risk of infection for susceptible animals and humans. Besides the clinical relevance for pets, T. crassiceps is a zoonotic parasite and can be also cause of severe cysticercosis in humans.

Unusual presentation of alveolar echinococcosis as prostatic and paraprostatic cysts in a dog.

BACKGROUND: Alveolar echinococcosis (AE) is caused by the larval stage (metacestode) of Echinococcus multilocularis. The domestic dog can act as a definitive host and harbor adult cestodes in its small intestine or become an aberrant intermediate host carrying larval stages that may cause severe lesions in the liver, lungs and other organs with clinical signs similar to AE in humans. CASE PRESENTATION: A case of canine AE, affecting the liver and prostate with development of multilocular hydatid paraprostatic cysts and possible lung involvement is described in an 8-year-old neutered male Labrador retriever dog.The dog presented with progressive weight loss, acute constipation, stranguria and a suspected soft tissue mass in the sublumbar region. Further evaluation included computed tomography of the thorax and abdomen, which revealed cystic changes in the prostate, a paraprostatic cyst, as well as lesions in the liver and lungs. Cytological examination of fine-needle aspirates of the liver, prostate and paraprostatic cyst revealed parasitic hyaline membranes typical of an Echinococcus infection and the presence of E. multilocularis-DNA was confirmed by PCR. The dog was treated with albendazole and debulking surgery was considered in case there was a good response to antiparasitic treatment. Constipation and stranguria resolved completely. Six months after the definitive diagnosis, the dog was euthanized due to treatment-resistant ascites and acute anorexia and lethargy. CONCLUSIONS: To the authors' knowledge, this is the first publication of an E. multilocularis infection in a dog causing prostatic and paraprostatic cysts. Although rare, E. multilocularis infection should be considered as an extended differential diagnosis in dogs presenting with prostatic and paraprostatic disease, especially in areas where E. multilocularis is endemic.

Situs ambiguus in a Brown Swiss cow with polysplenia: case report.

BACKGROUND: Laterality defects are rare in cattle and usually manifest as asplenia or polysplenia syndrome. These syndromes may be associated with situs ambiguus, which is a dislocation of some but not all internal organs. The objective of this report was to describe the clinical and post-mortem findings including the macroscopic and microscopic anatomy of selected organs in a cow with polysplenia and situs ambiguus. CASE PRESENTATION: A 3.5-year-old Brown Swiss cow was referred to the Department of Farm Animals, Vetsuisse Faculty, University of Zurich, because of poor appetite and recurrent indigestion. A diagnosis of situs ambiguus was based on the results of physical examination, ultrasonography, exploratory laparotomy and post-mortem examination. The latter revealed that the rumen was on the right side and lacked compartmentalisation. There were two spleens, one on the left (26.5 x 12.0 cm) and one on the right (20.5 x 5.5 cm), and the omasum was located craniolateral to the ruminoreticulum on the left. The abomasum was located on the right, although it had initially been displaced to the left. The three-lobed liver occupied the left and central cranioventral aspect of the abdominal cavity (cavum abdominis). Only the right and left hepatic veins (vena hepatica dextra and sinistra) drained into the thoracic segment of the caudal vena cava (vena cava caudalis), and histological changes in the liver were indicative of impaired haemodynamics. The mesojejunum was not fused with the mesentery of the spiral loop (ansa spiralis) of the ascending colon (colon ascendens). The latter was folded and the transverse colon (colon transversum) ran caudal to the cranial mesenteric artery (arteria mesenteria cranialis). Fibrotic constrictions were seen in the lumen of the caecum and proximal loop (ansa proximalis) of the ascending colon. Both kidneys were positioned retroperitoneally in a lumbar position. The lumbar segment of the caudal vena cava did not descend to the liver and instead drained into the right azygous vein (vena azygos dextra). CONCLUSIONS: Recurrent digestive problems and poor production in this patient may have been caused by a lack of rumen compartmentalisation, abnormal abomasal motility, constrictions in the large intestine (intestinum crassum) and fibrosis of the liver. The abomasum had abnormal motility most likely because it was anchored inadequately and only at its cranial aspect to the liver by the lesser omentum (omentum minus) and to the dorsal abdominal wall and rumen by a short greater omentum (omentum majus).

Clinical course of a malignant peripheral nerve sheath tumor in a Siberian tiger (Panthera tigris altaica).

A 14-year-old male Siberian tiger (Panthera tigris altaica) was admitted with an ulcerating mass on the right thoracic wall. Radiographic and computed tomographic evaluation indicated 2 isolated cutaneous masses without any signs of metastasis. Histology of a Tru-Cut biopsy revealed an anaplastic sarcoma with giant cells. Both tumors were resected with appropriate normal tissue margins. The size of the defect did not allow primary closure of the wound; therefore, a mesh expansion technique was attempted. Three months later, the tiger had to be euthanized due to extensive metastasis to the lungs. Histomorphological features and immunohistochemical results confirmed the diagnosis of malignant peripheral nerve sheath tumor. In contrast to domestic animal experience, the tumor had spread extensively to the lungs without local reccurrence in a short period of time. Correct diagnosis requires various immunohistochemical evaluations of the tumor tissue.

Introduction to the Swiss way of teaching veterinary pathology in the twenty-first century: application of e-learning modules.

The teaching of pathology within the veterinary medical curriculum extends through the entire training period and has a dual role. General pathology deals with principles of disease processes as a basis for understanding the reactions of a multi-cellular organism to adverse effects; organ pathology builds on the principles of general pathology and explains the malfunctions of individual organs. Pathology is heavily image dependent and best taught in a highly interactive manner. The Institute of Veterinary Pathology, University of Zurich (IVPZ), has been actively developing concepts for teaching pathology in the new veterinary curriculum, which demands more active participation from students, with 20% of their study time devoted to individual study using traditional materials (books, articles, etc.) and e-learning modules. The Swiss Virtual Animal Pathologist is designed to cover and support the central elements of the Veterinary Pathology curriculum of the Vetsuisse Faculty. The needs of students and staff of the participating institutions for an interactive learning platform to supplement the existing face-to-face lectures and tutorials are the highest priority of this initiative.