A 15-year-old 15.1-lb (6.9-kg) castrated male Lhasa Apso was presented to the Veterinary Medical Teaching Hospital at Texas A&M University for evaluation of chronic vomiting of several months' duration. The owner reported that initially the dog had been vomiting twice a week, but that two weeks before presentation the vomiting had increased to daily episodes. Initially, the vomitus had been white and foamy, but as the frequency of the vomiting had increased, the vomitus had changed to a bile-tinged fluid.

INITIAL PRESENTATION AND DIAGNOSTIC TESTS

At presentation, the dog's vital signs were normal (temperature = 100.9 F [38 C]; pulse rate = 100 beats/min with a strong pulse; respiratory rate = 36 breaths/min). On physical examination, the dog was alert and responsive with no pain noted on abdominal palpation. A IV/VI systolic murmur was auscultated and was loudest at the left apex. The results of a cranial nerve examination were normal except for bilaterally absent menace responses that were attributed to mature cataracts identified during a comprehensive ophthalmologic examination. The results of a complete blood count, serum chemistry profile, and urinalysis were normal except for isosthenuria (urine specific gravity = 1.015).

Radiography

A thoracic radiographic examination revealed mild enlargement of the left atrium, consistent with mitral insufficiency, but normal lung fields and pulmonary vessels. The results of an abdominal radiographic examination were unremarkable except for bilaterally small kidneys.

Abdominal ultrasonography

An abdominal ultrasonographic examination revealed a focally thickened pyloric antrum, but no obstruction was detected. Decreased corticomedullary differentiation of both kidneys was also noted. All other abdominal structures appeared to be normal. The pancreas was identified and was normal in size and echogenicity.

Gastroscopy

To further explore the cause of the vomiting, the dog was anesthetized, intravenous fluids were administered, and gastroscopy was performed, which revealed a large polyp-like growth in the pyloric antrum. This mass precluded the advancement of the endoscope into the duodenum. Multiple endoscopic biopsy samples were taken from the stomach wall, mass, and mucosa surrounding the pylorus. During the procedure, the dog had a brief period of hypotension but responded well to a continuous-rate infusion of dobutamine. The dog recovered well from anesthesia. Pending histologic examination results, the dog was discharged with no medications.

Histologic examination of the gastric mucosa and the associated pyloric growth revealed mild, diffuse lymphocytic-plasmacytic gastritis.

READMITTANCE AND ADDITIONAL DIAGNOSTIC TESTS

The owner reported that dog's vomiting episodes had increased in frequency after several days at home, so the dog was readmitted for an exploratory laparotomy. At admittance, the patient appeared to have no historical or physical signs of abdominal pain. The results of the preoperative blood work (complete blood count, serum chemistry profile) were normal.

Exploratory laparotomy

During surgery, a distinct nodular mass was identified within the pylorus. The pancreas appeared nodular but otherwise normal. A Billroth I procedure was performed to resect the pyloric mass. Despite gentle dissection, the pancreas was manipulated while performing the gastric and duodenal anastomosis.

The dog had no intraoperative complications and recovered well after surgery. Fluid therapy was continued overnight along with scheduled doses of hydromorphone for pain. Despite receiving nothing by mouth, the patient vomited large volumes of a light-brown fluid throughout the night.

Histopathologic examination results confirmed the pyloric mass to be a polyp associated with mild lymphocytic-plasmacytic gastritis.