Detection of monoclonality in intestinal lymphoma with polymerase chain reaction for antigen receptor gene rearrangement analysis to differentiate from enteritis in dogs.

The diagnosis of canine intestinal lymphoma by morphological examination is challenging, especially when endoscopic tissue specimens are used. The utility of detection of antigen receptor gene rearrangement by polymerase chain reaction (PARR) in canine lymphoma has been well established, but its usefulness to distinguish enteritis and intestinal lymphoma remains unclear. In this retrospective study we assessed clonality of 29 primary canine intestinal lymphoma, 14 enteritis and 15 healthy control cases by PARR analysis, using formalin-fixed, paraffin-embedded full-thickness tissue specimens. We could detect monoclonal rearrangements in 22 of 29 canine intestinal lymphomas [76%; 95% confidence interval (CI) 56-90%] and polyclonal rearrangements in all of the enteritis and healthy control cases (100%; CI 88-100%). We revealed a predominance of T-cell phenotype compared to B-cell phenotype (85%; CI 65-96% and 15%; CI 4-35%, respectively). We showed that PARR analysis contributes to differentiation of canine intestinal lymphoma from enteritis and to phenotyping of lymphomas.

Chronic Pancreatitis with Acinar-Ductal Metaplasia and Ductal Dysplasia in a Horse.

A 16-year-old Friesian gelding with relapsing colic was humanely destroyed during diagnostic laparotomy due to suspected abdominal neoplasia. On post-mortem examination, the pancreas appeared as a firm mass (20 × 8 × 8 cm). The cut surface had a lobular structure with multiple cavities. Histological examination revealed severe chronic fibrosing pancreatitis with acinar-ductal metaplasia and duct dysplasia, which was considered to be the cause of the recurrent colic. Formation of tubular complexes within a background of acinar-ductal metaplasia is similar to the regressive lesions detected in the human pancreas in the context of inflammation, duct obstruction, cystic fibrosis and neoplasia. Pancreatic acinar-ductal metaplasia and ductal dysplasia are considered to be preneoplastic conditions in man and in the mouse.

[Aortic thrombosis in a calf]. / Aortenthrombus bei einem Kalb.

A two month-old female Simmental calf was presented with sensomotoric dysfunction and recumbency. Neurologic examination revealed dysfunction of the cerebral cortex and paralysis of both hind limbs. Examination of the skeletal system revealed a marked reduction of the skin temperature of both hind limbs and the absence of femoral pulse. Examination of cerebrospinal fluid yielded physiological parameters. The radiographic examination of the vertebral column, hip and femur on both sides revealed no evidence of alteration of the bone structures. Thiamine pyrophosphate test indicated thiamine deficiency. Based on these findings a tentative diagnosis of cerebrocortical necrosis and aortic thrombosis were made and the animal was euthanised. Post mortem examination yielded thrombosis of the abdominal aorta cranial to the branching of the iliac arteries and consecutive necrosis of the skeletal muscle of the hind limbs. Possible causes of pathogenesis are discussed.

Endoscopically visualized lesions, histologic findings, and bacterial invasion in the gastrointestinal mucosa of dogs with acute hemorrhagic diarrhea syndrome.

BACKGROUND: Etiology of hemorrhagic gastroenteritis (HGE) syndrome in dogs is unknown and histopathologic and microbial investigations have only been performed post mortem. OBJECTIVE: To identify characteristic intra vitam endoscopic and histologic mucosal lesions, as well as bacterial species, within the mucosa of dogs with HGE. ANIMALS: Ten dogs diagnosed with HGE were included. Eleven dogs with gastroduodenoscopy and different intestinal diseases were used as controls for microbial changes. Dogs pretreated with antibiotics or diagnosed with any disease known to cause bloody diarrhea were excluded from the study. METHODS: In this prospective study, gastrointestinal biopsies were collected from 10 dogs with HGE. Endoscopic and histologic changes were assessed according to WSAVA guidelines. Biopsies from the stomach, duodenum, ileum, and colon were investigated by histology and by immunohistochemistry for the presence of Clostridium spp. and parvovirus. The first duodenal biopsy taken with a sterile forceps was submitted for bacterial culture. RESULTS: Acute mucosal lesions were only found in the intestines, not in the stomach. Clostridium spp., identified as Clostridium perfringens in 6/9 cases, were detected on the small intestinal mucosa in all dogs with HGE, either by culture or immunohistopathology. In the control group, C. perfringens could only be cultured in one of 11 dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: The results of this study demonstrate an apparent association between C. perfringens and the occurrence of acute hemorrhagic diarrhea. The term "HGE," which implies the involvement of the stomach, should be renamed as "acute hemorrhagic diarrhea syndrome."