Fibrosing gastrointestinal leiomyositis as a cause of chronic intestinal pseudo-obstruction in an 8-month-old dog

An 8-month-old, female, mixed-breed dog presented to the Iowa State University Veterinary Teaching Hospital with a 1-month history of vomiting and diarrhea. An exploratory laparotomy was performed revealing markedly distended and fluid-filled small and large intestines that were not obstructed. The clinical condition of the dog did not improve subsequent to exploratory surgery, and it was euthanized. At necropsy, both the small and large intestines were distended (approximately 4 cm in diameter) and fluid-filled, and the wall was thin. The abdominal cavity contained approximately 500 ml of a brownish clear fluid. Microscopic lesions of the intestines were confined to the intestinal tunica muscularis and muscularis mucosae and consisted of locally extensive-to-diffuse replacement of the smooth muscle by fibrous tissue and multifocal infiltration by a moderately dense mononuclear inflammatory infiltrate. A unique finding was the presence of similar microscopic lesions in the tunica muscularis of the urinary bladder and stomach.     

Intra-laryngeal foreign body as an unusual cause of dyspnoea in a dog

Severe dyspnoea in a young puppy was relieved by the removal of a small piece of smokeless fuel from the infraglottic cavity of the larynx by ventral laryngotomy.     

Fibrocartilaginous emboli as the cause of ischemic myelopathy in a dog.

Acute hemiplegia and Horner's syndrome developed in a 6-year-old female black Labrador Retriever 24 hours after a day of exercise. Radiographic, cerebrospinal fluid, and electromyographic studies did not detect the site or nature of the suspected cervical lesion. The dog showed no improvement after evaluation for 5 days on corticosteroid and antibiotic therapy. Gross and microscopic examination revealed the presence of an ischemic infarct in the C6 segment of the cervical spinal cord and associated fibrocartilaginous emboli. The nature of the clinical signs and the pathologic findings in this case are similar to previous reports of human and canine cases.     

Chronic primary splenic torsion with peritoneal adhesions in a dog: case report and literature review

Primary splenic torsion in dogs is uncommon and can occur in acute or chronic form. The chronic form is difficult to diagnose because the clinical signs are vague and sometimes intermittent. A dog with a history of diaphragmatic hernia repair two years previously presented with chronic, vague clinical signs and an abdominal mass. The mass was revealed to be spleen on ultrasonography. On exploratory laparotomy, the dog was found to have a splenic torsion of approximately 180 degrees with mature, fibrous adhesions retaining the spleen in a torsed position. A splenectomy was performed, and the dog recovered uneventfully with complete resolution of prior clinical signs. Prognosis for dogs with splenic torsion is good, although complications are relatively common.     

Protothecosis as a cause of chronic diarrhoea in a dog

The clinical form of the protothecosis in animals is most commonly observed in countries with a warm and moist climate, only a few reports describing cases of this infection in cooler areas of the word exist. In the case of large bowel infection in dogs, organisms colonise the lamina propria and submucosa causing severe necrotizing ulcerative or haemorrhagic enterocolitis. In this report the intestinal form of protothecosis in 1.5-year-old, male, mongrel dog with chronic hemorrhagic diarrhoea is described. History revealed that the dog spent some time in the countryside and afterwards diarrhoea with fresh blood appeared. The results of morphological and biochemical blood analysis were normal and stool examination did not reveal the presence of parasites. Treatment with anti-inflammatory doses of prednisone, metronidazole and enrofloxacin followed by sulphasalazine resulted in a short period of improvement, but was followed by deep deterioration of animal status. Because of the relapse diagnostic laparotomy was performed and tissue samples of the colon and jejunum were obtained for histopathology. On the basis of the clinical signs, exploratory laparotomy findings and histopathology the diagnosis of canine intestinal prototecosis was made and medical treatment was recommended.     

Induction of peritoneal adhesions with small intestinal ischaemia and distention in the foal

Twenty-two foals were divided into groups of intestinal distension and intestinal ischaemia as methods to induce peritoneal adhesions. In the first group, the lumen of a segment of distal small intestine was occluded without extramural vascular compromise and distended with lactated Ringer's solution to a constant pressure of 25 cm H2O for 2 h within the abdomen. The ischaemic group underwent 70 mins total vascular occlusion of identical segments of bowel. Serosal biopsies were obtained before and after each experimental procedure and following 60 mins of reperfusion. Similar biopsies were harvested from a control group of foals with no bowel occlusions. The foals were destroyed 10 days after surgery and tissues collected for histological and ultrastructural evaluation. Experimental and control mesothelial surfaces were denuded histologically immediately after experimental occlusions. Serosal oedema and cellular infiltration were observed following reperfusion of the ischaemic segments but were present immediately after 2 h of distension. All foals had developed bowel-to-bowel and bowel-to-mesentery adhesions of the experimental segments. Control foals under 30 days old exhibited mesenteric contraction and thickening of the isolated segment whereas those older than 30 days had little or no mesenteric thickening or contraction. Histologically, in the experimental segments, fibrous tissue had formed on the outer boundary of the original serosa, and new mesothelial-like cells were present on the surface of fibrous tissue in some areas. Some serosal fibrosis was also seen in most of the control segments.     

Atrial myocarditis as a cause of sinus arrest in a dog

A 10-year-old male cairn terrier cross was presented with a history of myxomatous mitral valve disease diagnosed six months previously and with a four-week history of intermittent collapse. On 24 hour electrocardiograph (Holter) analysis, periods of no discernable electrical cardiac activity, which coincided with three collapsing episodes, were identified. Unfortunately, on re-presentation for removal of the Holter monitor, the dog collapsed and died. A post-mortem examination was conducted, and histology of the right and left atrium showed evidence of myocarditis. This is the first reported case, to our knowledge, of collapse because of electrical asystole in a dog with atrial myocarditis.     

Teres minor myopathy as a cause of lameness in a dog

A case of a teres minor myopathy causing chronic lameness in a flve-yearold working iabrador retriever Is described. Uitrasonography was used to assist in detection of the condition and a definitive diagnosis was made by histological examination after muscle excision. Medical treatment was ineffective, but excision of the affected muscle resulted in complete resolution of the lameness with no apparent adverse affects on joint function. The aetiology of this condition Is unknown.     

A thymoma as a cause of oesophageal obstruction in a dog

A case of oesophageal obstruction in a dog was caused by an intraluminal, pedunculated thymoma. The tumour was surgically excised and, eventually, the dog made a full recovery. Two days after being discharged from hospital, the dog developed acute myositis involving the temporal muscles which responded, without untoward sequelae, to steroid therapy.     

Bleeding tendency as a cause of epistaxis in the dog

Summary

Based upon a survey of the pathophysiology of haemostasis, the causes of epistaxis in the dog are discussed, and guidelines for a diagnostic and therapeutic approach are given.     

Transmural pyloric perforation associated with naproxen administration in a dog

Naproxen, a nonsteroidal anti-inflammatory drug developed for use in man for relief of pain and discomfort associated with rheumatoid arthritis, was believed responsible for a transmural pyloric perforation in a dog. The perforation was repaired surgically.     

Bleeding tendency as a cause of epistaxis in the dog

Based upon a survey of the pathophysiology of haemostasis, the causes of epistaxis in the dog are discussed, and guidelines for a diagnostic and therapeutic approach are given.     

Necrotizing lymphadenitis as a cause of acute abdominal distress in a dog

An unusual case of acute abdominal distress caused by necrotizing lymphadenitis of the retroperitoneal lymph nodes in a 10-year-old Springer Spaniel is presented. The retroperitoneal lymph nodes were severely distended, but no other abnormalities were found in the abdominal cavity or elsewhere. Biopsy revealed acute necrotizing lymphadenitis, which should be considered in the differential diagnosis of acute abdominal disorders in the dog.     

Multiple magnet ingestion as a cause of septic peritonitis in a dog

A 1 yr old male castrated Yorkshire terrier was referred after ingesting magnets. Dehydration, fever, tachycardia, and abdominal pain were noted on physical examination. Abdominal radiographs revealed two radiopaque foreign objects in close proximity to each other with decreased abdominal detail. Surgical exploration identified magnets adhered together in the omentum with perforations present in the transverse colon and stomach. The perforations were closed and a Jackson-Pratt continuous suction drain was placed. Septic peritonitis secondary to intestinal perforation from magnet ingestion was successfully treated with a combination of surgery and a closed suction drain.     

Deciduoid peritoneal mesothelioma in a dog

Deciduoid mesothelioma is a rare variant of epithelial mesothelioma, up to now only described in human pathology, which bears remarkable cytomorphologic resemblance to the endometrium of pregnancy, termed decidua. A case of peritoneal mesothelioma with deciduoid features in a 10-year-old, female dog is reported. Multiple whitish-gray nodules (1-5 mm in diameter) in parietal peritoneum and mesentery were histologically composed of large, proliferating, polygonal or ovoid cells with an abundant eosinophilic, glassy cytoplasm. Immunohistochemical evaluation indicated that the neoplastic cells coexpressed cytokeratin and vimentin with strong and diffuse cytoplasmic staining, and ultrastructural analysis showed long and slender mesothelial-type microvilli; these findings confirmed the mesothelial origin of the tumor.