ULTRASONOGRAPHIC DETECTION OF ADRENAL GLAND TUMOR AND URETEROLITHIASIS IN A GUINEA PIG

A 5-year-old guinea pig was presented to the University of Berne Small Animal Radiology Department for an ultrasound examination of the abdomen to confirm a suspected diagnosis of Cushing's syndrome. The patient had bilateral alopecia, was apathic and obese. Ultrasonographically, a tumor of the left adrenal gland, obstruction of the left ureter by an ureterolith, as well as hydronephrosis of the left kidney were detected. During surgery to relieve the ureteral obstruction the adrenal gland tumor was removed. The guinea pig died post-operatively due to blood loss. The left adrenal gland tumor was found histopathologically to be an adenoma and the right adrenal gland also had multiple small adenomas, but grossly appeared normal. The ureterolith was analyzed and found by x-ray diffraction to consist of calcium carbonate.     

URETEROLITHIASIS AND PAPILLOMA FORMATION IN THE URETER OF A GUINEA PIG

A 5-year-old guinea pig with suspected urolithiasis was presented for radiology and ultrasound examinations of the abdomen. Radiographically, an irregular-shaped mineral opacity was detected in the area of the urinary bladder. Ultrasonographically, pyelectasia of the right kidney, hydroureter with an ureterolith cranial to a thickened ureter wall close to the ureterovesical junction, and a thickened urinary bladder wall were detected. Histopathologically, the thickened ureter wall was found to be a papilloma. The ureter calculus consisted of 100% calcite.     

Primary ureteral giant cell sarcoma in a Pomeranian

An 8-year-old male neutered Pomeranian dog was presented to the Veterinary Teaching Hospital at Oregon State University for surgical treatment of hydronephrosis of the left kidney and a left cranial abdominal mass. A primary ureteral mass was found during exploratory surgery, and the mass was resected and ureteral anastomosis was performed. Cytologic evaluation of the mass revealed 3 distinct cell populations, including a large number of multinucleated giant cells, a moderate number of thin spindle-shaped cells, and cohesive clusters of transitional epithelial cells. The cytologic diagnosis was giant cell sarcoma. The diagnosis was confirmed by histologic examination, and immunohistochemical staining was performed. The spindle-shaped cells and multinucleated giant cells were both immunoreactive for vimentin and spindle-shaped cells for S-100. Tumor cells did not express wide-spectrum cytokeratin, broad-spectrum muscle actin, smooth muscle actin, sarcomeric actin, desmin, BLA36, Mac 387, synaptophysin, neuron-specific enolase, glial fibrillary acid protein, or von Willebrand factor. These findings are most consistent with an anaplastic sarcoma with giant cells. This is the first case report of a primary ureteral giant cell sarcoma in a dog.     

IMAGING DIAGNOSIS—LEFT RETROCAVAL URETER AND TRANSPOSITION OF THE CAUDAL VENA CAVA IN A DOG

Retrocaval ureter and transposition of the caudal vena cava are each, rare developmental anomalies. We describe the usefulness of static fluid magnetic resonance urography and dynamic contrast-enhanced magnetic resonance urography in the diagnosis of these anomalies. Basic techniques, benefits, and drawbacks of magnetic resonance urography are presented.     

Urinary Bladder incarceration and Infarction by an Intra-Abdominal Fat Pad in a Virginia Opossum (Didelphis Virginiana)

A 2.5-year-old, female opossum had acute stranguria. Based on radiography and ultrasonographic examination a cystic structure was identified in the caudal abdomen associated with bilateral hydroureter and hydronephrosis. This structure contained a neutrophilic fluid, determined to be urine. There was a neutrophilic leukocytosis. Serum chemistry values were within normal limits. The opossum was euthanized. An intra-abdominal fat pad incarceration of the urinary bladder above the trigone was present, resulting in complete obstruction of the urinary bladder and partial obstruction of the ureters. Vessels to the bladder were involved in the incarceration which resulted in vascular compromise and infarction of the bladder. Mild to moderate hydroureter and hydronephrosis were present.     

OSSEOUS METAPLASIA IN THE RENAL PELVIS OF A DOG WITH HYDRONEPHROSIS

A 3-year-old male Sheltie dog was presented with abdominal distension, diarrhea, and vomiting. Hematologic and blood chemistry studies revealed a mild anemia and a few leukocytes in the urine. Radiographic examination was made, and a large mass with calcified trabeculae was present in the ventral right cranial quadrant of the abdomen. Exploratory celiotomy was performed, and a mass identified as the right kidney was removed. The excised kidney was cystic and multiloculated, and contained areas of bone and cartilage. This mass weighed 1120 g and was in excess of ten percent of the dog's body weight. Transitional epithelium can stimulate osseous metaplasia. The presence of both tissues in a biopsy specimen might indicate urinary tract disease.     

CALCIUM OXALATE URETEROLITH IN A CAT

A 4-year-old cat was presented for polyuria and polydipsia. Unilateral hydronephorosis and hydroureter was diagnosed on ultrasound examination of the abdomen, and right ureteral calculi were seen in survey abdominal radiographs. Intravenous urography confirmed hydronephrosis and indicated poor renal funttion in the right kidney. Surgical removal of the ureteral calculus improved right renal function. Analysis of the calculus indicated composition of calcium oxalate, an uncommon calculus in cats.     

CLINICAL SIGNIFICANCE OF RENAL PELVIC DILATATION ON ULTRASOUND IN DOGS AND CATS

Renal pelvic dilatation is often recognized sonographically in dogs and cats, but ranges of measurements expected with different urologic conditions remain unknown. Ultrasound images of 81 dogs and 66 cats with renal pelvic dilatation were reviewed, and six groups were formed based on medical records: (I) clinically normal renal function, and (II) clinically normal renal function with diuresis; (III) pyelonephritis; (IV) noninfectious renal insufficiency; (V) outflow obstruction; (VI) miscellaneous nonobstructive anomalies. Medians for maximal pelvic width (range) for group I was 2.0 mm (1.0–3.8) in 11 dogs, and 1.6 mm (0.8–3.2) in 10 cats; for group II, 2.5 mm (1.3–3.6) in 15 dogs, and 2.3 mm (1.1–3.4) in 16 cats; for group III, 3.6 mm (1.9–12.0) in nine dogs, and 4.0 mm (1.7–12.4) in seven cats; for group IV, 3.1 mm (0.5–10.8) in 33 dogs, and 2.8 mm (1.2–7.3) in 13 cats; for group V, 15.1 mm (5.1–76.2) in six dogs, and 6.8 mm (1.2–39.1) in 17 cats; and for group VI, 3.8 mm (1.2–7.6) in seven dogs, and 3.0 mm (1.3–7.5) in three cats. Pelvic width in group I was lower than in groups III–V (P=0.0001), but did not significantly differ from group II. Pelvic width ≥13 mm always indicated obstruction. While the proportion of bilateral pelvic dilatation was not different among groups, the difference in pelvic width (maximal–minimal) was greater in group V vs. groups I, II, and IV (P=0.0009). These results confirm that renal pelvic dilatation can be detected sonographically in dogs and cats with clinically normal renal function, and that it increases with renal insufficiency, pyelonephritis, or outflow obstruction. Nevertheless, renal pelvic width varies substantially within groups and should be interpreted with caution.     

Bilateral hydronephrosis secondary to anticoagulant rodenticide intoxication in a dog

Objective: To describe an unusual site of hemorrhage in a case of anticoagulant rodenticide toxicity. Case summary: A dog treated for Brodifacoum anticoagulant rodenticide intoxication was referred for treatment of thrombocytopenia and dysuria. Sonographic examination revealed a large blood clot within the urinary bladder, extending proximally along both ureters, and a bilateral hydronephrosis. In this dog, management of the vitamin K₁‐dependent coagulopathy was unusually complicated by uremia and thrombocytopenia. New information provided: This is the first reported case of hydronephrosis secondary to anticoagulant rodenticide intoxication in a dog.     

ULTRASONOGRAPHIC DIAGNOSIS OF HYDRONEPHROSIS IN A COW

A ruptured right kidney was diagnosed in a cow with clinical signs of mild intermittent abdominal pain and no laboratory evidence of renal failure. Ultrasonography of the kidneys demonstrated unilateral hydronephrosis and retroperitoneal fluid. A unilateral nephrectomy using a staple instrument was performed. Ultrasonographic evaluation allowed an early and accurate diagnosis with subsequent successful surgical intervention and treatment.