[Spinal nephroblastoma at an uncommon localization in a dog]. / Spinales Nephroblastom in ungewöhnlicher Lokalisation bei einem Hund.

A 7-month-old intact male Otterhound was presented for diagnosis of progressive hindlimb paresis. The neurological examination revealed a severe ambulatory paraparesis localised to the left-sided region of the lower motor neuron (L4-S1). Magnetic resonance imaging was suggestive for an intradural-extramedullary neoplasia at the fifth lumbar vertebra. Surgical exploration demonstrated an intradural-extramedullary mass, which partially invaded the spinal cord. The mass was removed with the exception of the intramedullar part, and the diagnosis of a nephroblastoma was made histopathologically. Following radiation therapy, the dog fully recovered and displayed no signs of neurological dysfunction 9 months after surgery.

Alopecia areata in Eringer cows.

Alopecia areata is a hair loss disorder in humans, dogs and horses with a suspected autoimmune aetiology targeting anagen hair follicles. Alopecia areata is only sporadically reported in cows. Recently, we observed several cases of suspected alopecia areata in Eringer cows. The aim of this study was to confirm the presumptive diagnosis of alopecia areata and to define the clinical phenotype and histopathological patterns, including characterization of the infiltrating inflammatory cells. Twenty Eringer cows with alopecia and 11 Eringer cows without skin problems were included in this study. Affected cows had either generalized or multifocal alopecia or hypotrichosis. The tail, forehead and distal extremities were usually spared. Punch biopsies were obtained from the centre and margin of alopecic lesions and normal haired skin. Histological examination revealed several alterations in anagen hair bulbs. These included peri- and intrabulbar lymphocytic infiltration, peribulbar fibrosis, degenerate matrix cells with clumped melanosomes and pigmentary incontinence. Mild lymphocytic infiltrative mural folliculitis was seen in the inferior segment and isthmus of the hair follicles. Hair shafts were often unpigmented and dysplastic. The large majority of infiltrating lymphocytes were CD3(+) T cells, whereas only occasional CD20(+) lymphocytes were present in the peribulbar infiltrate. Our findings confirm the diagnosis of T-cell-mediated alopecia areata in these cows. Alopecia areata appears to occur with increased frequency in the Eringer breed, but distinct predisposing factors could not be identified.

Improved polymerase chain reaction-based method to detect early-stage epitheliotropic T-cell lymphoma (mycosis fungoides) in formalin-fixed, paraffin-embedded skin biopsy specimens of the dog.

In the dog, early-stage epitheliotropic T-cell lymphoma (ETCL) can clinically and histologically mimic a large range of inflammatory dermatoses and often progresses rapidly to a more aggressive tumor stage. Early diagnosis of ETCL is essential to proceed with a specific oncologic therapy that is favorable for the prognosis. In the present study, an improved method for the detection of T-cell receptor gamma (TCRgamma) rearrangement was developed by designing a new set of consensus primers to amplify the different forms of rearranged canine TCRgamma gene sequences by polymerase chain reaction. The amplicons were analyzed by conventional polyacrylamide gel electrophoresis, which requires minimal specific equipment and may be performed in almost every pathology laboratory at low costs. The method proved to be highly specific and sensitive to detect early ETCL in formalin-fixed, paraffin-embedded biopsy specimens, providing an efficient tool for veterinary pathologists to distinguish early neoplastic from reactive cutaneous T-cell infiltrates (tumor-specific marker) or to discriminate T-cell lymphoma from B-cell lymphomas or nonlymphoid neoplasms (T-cell lineage marker). By direct sequencing analysis of amplified TCRgamma gene sequences, ETCL was found to rearrange exclusively the joining (J) 4 region, which suggests specific biology for primary cutaneous T-cell lymphomas. Also, a novel (seventh) functional J region in the TCRgamma gene, localized approximately 2.3 kb upstream of J5, was identified.

Hormographiella aspergillata keratomycosis in a dog.

A 4-year-old, female, Border Collie was presented to the University of Bern Veterinary Teaching Hospital, because of a corneal lesion of 10 days duration. The axial cornea presented a whitish fluorescein-positive plaque with irregular margins. A diagnosis of keratomycosis was made based on cytology. Medical therapy with local broad-spectrum antibiotic and fluconazole was instituted. After 1 week of treatment, the improvement was deemed unsatisfactory. Therefore, a lamellar keratectomy and conjunctival pedicle flap were performed. After surgery, the cornea healed uneventfully. Histology confirmed the diagnosis of keratomycosis. The fungus could not be grown in culture and a precise etiological diagnosis could only be obtained with genetic identification of the fungus. A PCR technique was used to amplify the fungal genome from the cornea. Hormographiella aspergillata, the asexual reproductive form of the basidiomycete Coprinopsis cinerea, was identified. As advised in human medicine, we encourage the use of this molecular technique to obtain an early species diagnosis, allowing targeted medical therapy.

Evaluation of lymphocyte apoptosis in dogs with inflammatory bowel disease.

OBJECTIVE: To determine whether lymphocyte apoptosis in intestinal mucosae is more common in healthy dogs than dogs with inflammatory bowel disease (IBD) and whether numbers of apoptotic cells increase after successful treatment of affected dogs. ANIMALS: 8 dogs with IBD (IBD dogs) and 8 healthy control dogs. PROCEDURES: Biopsy specimens of the duodenum and colon were obtained via endoscopy from dogs with IBD before and after 10 weeks of standard treatment and compared with specimens obtained from control dogs. Expression of activated caspase 3 (Casp3), caspase-cleaved fragment p85 from poly-ADP-ribose polymerase (PARP), and B-cell leukemia/lymphoma 2 (Bcl-2) was measured in the duodenal (villous tip and base) and colonic mucosae. RESULTS: Expression of Casp3 was greater in the duodenal villous tips of control dogs, compared with expression in similar tissues from dogs with IBD before or after treatment. Despite clinical improvement of dogs with IBD, expression of Casp3 did not increase after treatment. Expression of PARP did not differ between groups at any time point. Expression of Bcl-2 was greater at all 3 tissue sites in control dogs, compared with expression at the same sites in dogs with IBD. Furthermore, Bcl-2 expression in duodenal villous tips was higher in dogs with IBD after treatment but was not higher elsewhere. In control dogs, expression patterns for all 3 markers were similar between sites (villous tip > villous base > colon). CONCLUSIONS AND CLINICAL RELEVANCE: Expression of Casp3 in lymphocytes in duodenal villous tips was significantly reduced in dogs with IBD, compared with expression in healthy dogs, but no increase was detected following successful treatment of IBD. Increased expression of Bcl-2 may be a potential marker of the success of treatment.

A nodular granulomatous posthitis caused by Halicephalobus sp. in a horse.

This report describes a case of nodular posthitis caused by Halicephalobus gingivalis in a 24-year-old warmblood horse. Macroscopic examination revealed a multinodular, partially ulcerated mass on the external lamina of the prepuce. Nematode migration from unfixed biopsy material in phosphate-buffered saline revealed adult nematodes with the typical morphological features of H. gingivalis: distinctive rhabditiform oesophagus with corpus, isthmus and bulb and the dorsoflexed ovary. The main histopathological features consisted of submucosal confluent granulomatous foci containing cross- and tangential sections of larval and adult nematodes surrounded by cellular debris, epitheloid macrophages, multinucleated giant cells, lymphocytes and plasma cells. Therapy including oral administration of moxidectin and local application of an ointment containing prednisolone and moxidectin was initiated but clinical response was poor. Five months later, the nodular mass was still present and histologically, the same lesions with numerous intact nematodes were identified. In the present case, a localized infection with granuloma formation in the area of the prepuce was observed. Clinically, it cannot be distinguished from other nematode infections or even from a squamous cell carcinoma. An accurate clinical examination followed by histopathological and parasitological examinations was necessary to establish the final diagnosis. This case is unusual in that the lesions were locally very extensive (10 cm), but they remained confined to the preputium and the nematodes did not spread haematogenously to other internal organs.