Ultrasound-guided percutaneous drainage for treatment of pyonephrosis in two dogs

Pyonephrosis refers to suppurative destruction of the parenchyma of the kidney with complete or nearly complete loss of renal function. In dogs, nephrectomy is still the most common treatment for pyonephrosis; however, in the present report, a method for percutaneous ultrasound-guided drainage of the renal pelvis in dogs with pyonephrosis that does not require local or general anesthesia was described, and results of the procedure in 2 dogs were reported. Briefly, dogs were positioned in lateral recumbency with the affected side up, and skin overlying the affected kidney was aseptically prepared. The dilated renal pelvis was punctured percutaneously, under ultrasound guidance, with a 22-gauge needle, and a sample of material was obtained for analysis. The needle was then replaced with an IV catheter, and as much pus as possible was removed from the renal collecting system. A povidone iodine solution was then used to lavage the renal pelvis. Ultrasound-guided drainage and lavage of the renal pelvis was repeated daily until the renal pelvis was so small that it could no longer be punctured. Both dogs recovered and were reported by the owners to be healthy after the procedure.     

LYMPHOMA AFFECTING THE URINARY BLADDER IN THREE DOGS AND A CAT

Three dogs and one cat with lymphoma affecting the urinary bladder are reported and the findings on abdominal radiographs and ultrasound are described. Mural lesions representing lymphoma affecting the urinary bladder were identified ultrasonographically in all animals. The most common complications associated with urinary bladder lymphoma were hydronephrosis and hydroureter. In two patients contrast radiography was necessary to detect leakage of urine in the peritoneal and retroperitoneal space. The radiographic and ultrasonographic signs were similar to those reported with other urinary bladder neoplasms; hence urinary bladder lymphoma could not be distinguished from the more common urinary bladder neoplasms, such as transitional cell carcinoma. It is important to include lymphoma in the differential diagnosis of urinary bladder wall thickening and mural mass in dogs and cats.     

Ultrasonographic Features of the Chinchilla (Chinchilla lanigera) Kidney

Nine healthy chinchillas (Chinchilla lanigera) were used to characterize the ultrasonographic size and anatomical structure of the kidneys. Sonographic evaluations were performed with the aid of a 12-MHz linear probe. Kidney measurements included total width and length, total organ area, cortex and medullary thickness, and width and length of the renal pelvis. Based on the results of this study, normal chinchilla kidneys are located retroperitoneally, with the right kidney in a more cranial location than the left. Statistical analysis showed that measurements were similar between contralateral kidneys and between sexes. Chinchilla kidneys have a single papilla and a wider renal pelvis compared with the renal pelvis of dogs and cats. Moreover, chinchilla kidneys have a longer medullary area. The data herein may aid diagnosis of renal disease in chinchillas, avoiding misinterpretations of ultrasonic findings involving the kidneys of this species.     

Transitional cell carcinoma of the renal pelvis in two dogs

Transitional cell carcinoma (TCC) of the renal pelvis was found in two dogs, a 7-year-old male English Setter and a 11-year-old female Shetland shepherd. Affected dogs were presented for clinical examination without any specific symptoms but haematuria in case 1 and occurrence of whitish material in the urine of case 2; neoplastic disorders were discovered with ultrasonographic investigation and fine needle aspiration biopsy. Histopathological examination was carried out after nephrectomy and ureterectomy of the affected kidney of both dogs, and confirmed the diagnosis of non-invasive and low grade TCC in case 1 and of infiltrating TCC in case 2. The clinical, gross, cytological and histopathological features of these rare tumours originating from transitional epithelium of the renal pelvis are reported.     

Post-traumatic paraureteral urinoma in a cat

A retroperitoneal urinoma (uriniferous pseudocyst) was diagnosed in a domestic shorthair cat exhibiting a sublumbar swelling two weeks after a road traffic accident. Plain radiography revealed a soft tissue opacity in the left retroperitoneal space. Intravenous urography and fine-needle aspiration were diagnostic. Contrast was seen pooling in the dilated ipsilateral renal pelvis and proximal ureter. Fluid aspirated from the retroperitoneal space had a creatinine level five times that of serum. Surgical drainage followed by nephrectomy and omentalisation of the pseudocyst was curative.     

ULTRASONOGRAPHIC FINDINGS IN 14 DOGS WITH ECTOPIC URETER

To evaluate ultrasonography as an alternative to contrast radiography for diagnosis of ectopic ureter in dogs, ultrasonography of the urinary tract was performed prospectively in a series of urinary incontinent dogs anesthetized for contrast radiography. Fourteen dogs had ectopic ureter based on surgical, necropsy or unequivocal contrast radiographic findings. There were eight females and six males of a variety of breeds; five were Labrador retrievers. Mean (range) age at the time of diagnosis was 1.2 (0.2–4) years for females and 3.5 (0.3–5) for males (p < 0.05). Ectopic ureters were unilateral in five dogs (2 left; 3 right) and bilateral in nine dogs. Both ultrasound images and contrast radiographs were positive for 21 (91%) ectopic ureters; the same two ectopic ureters were not detected using either modality. The termination of each of the five normal ureters was visible on ultrasound images; two (40%) were visible on radiographs. Other ultrasonographic findings included dilatation of the ectopic ureter and/or ipsilateral renal pelvis in ten (43%) instances, evidence of pyelonephritis in two dogs (with enlargement of the contralateral kidney in one dog), and urethral diverticuli in one dog. Ultrasonography is a practical diagnostic test for ectopic ureter in dogs. In this series there was close correlation between the ultrasonographic and contrast radiographic findings for each ectopic ureter, but ultrasonography enabled more accurate determination of normal ureteral anatomy.     

LESIONS OF THE RENAL PELVIS AND PROXIMAL URETER IN VARIOUS NEPHRO-UROLOGICAL CONDITIONS: AN ULTRASONOGRAPHIC STUDY

The applicability of ultrasonography was studied in the diagnosis of lesions of the renal pelvis and ureter in 10 dogs. Ultrasonographic findings of processes associated with dilatation and concretion formation in the renal pelvis were described and the differential diagnosis of the lesions was discussed. The authors propose a new classification system for judging processes characterized by dilatation of the renal pelvis. Experience suggests that ultrasonography is an effective procedure in the diagnosis of certain diseases of the upper urinary tract in dogs.     

ULTRASONOGRAPHIC FEATURES OF INTESTINAL ENTRAPMENT IN DOGS

The clinical and ultrasonographic features of postoperative intestinal entrapment were assessed in five dogs. Four had vomiting and lethargy, and one had peracute collapse and hematochezia. Ultrasonographic findings in four of five dogs were similar, being characterized by focally hyperechoic mesentery and abdominal effusion, surrounding a single loop of amotile and dilated intestine. In some dogs, the affected intestinal loop had a thickened or corrugated wall, or alteration of wall layering. In one dog, the site of entrapment could be directly visualized. In the most severely affected dog, a large volume of echogenic peritoneal effusion was present, as well as fluid dilation of multiple intestinal loops. The ultrasonographic appearance of intestinal entrapment is similar to that of intestinal perforation or infarction by other causes.     

Clinical, clinicopathologic, radiographic, and ultrasonographic characteristics of intestinal lymphangiectasia in dogs: 17 cases (1996-1998)

OBJECTIVE: To characterize the clinical, clinicopathologic, and imaging findings in dogs with intestinal lymphangiectasia and to compare the histologic grade of lymphangiectasia with clinicopathologic and imaging abnormalities. DESIGN: Retrospective study. ANIMALS: 17 dogs with a histologic diagnosis of intestinal lymphangiectasia. PROCEDURE: Medical records of dogs with a histologic diagnosis of intestinal lymphangiectasia were reviewed for signalment, history, clinical signs, results of exploratory laparotomy, and clinicopathologic, radiographic, ultrasonographic, and histologic findings. RESULTS: Mean age of dogs was 8.3 years; the most common clinical signs were diarrhea, anorexia, lethargy, vomiting, and weight loss. Abnormal physical examination findings included dehydration, ascites, and signs of pain on palpation of the abdomen. The most notable clinicopathologic findings were low serum ionized calcium concentration and hypoalbuminemia. Abdominal ultrasonography was performed in 12 dogs and revealed intestinal abnormalities in 8 dogs and peritoneal effusion in 7 dogs. Exploratory laparotomy revealed abnormalities in 9 of 16 dogs including thickened small intestine, dilated lacteals, lymphadenopathy, and adhesions. On histologic examination of the small intestine, concurrent inflammation was observed in 15 of 17 dogs, crypt ectasia in 5 of 17, and lipogranulomas in 2 of 17. CONCLUSIONS AND CLINICAL RELEVANCE: Intestinal lymphangiectasia in dogs appears to be a heterogeneous disorder characterized by various degrees of panhypoproteinemia, hypocholesterolemia, lymphocytopenia, and imaging abnormalities. In most dogs, the severity of hypoalbuminemia appears to offer the best correlation with severity of histologic lesions of lymphangiectasia. Imaging abnormalities are common in dogs with intestinal lymphangiectasia but are not specific enough to differentiate this disorder from other gastrointestinal disorders, nor are they predictive of histologic severity.     

Circumcaval ureter associated with an intrahepatic portosystemic shunt in a dog

CASE DESCRIPTION: A 4-month-old Bernese Mountain Dog was examined because of shifting hind limb lameness and lethargy of 2 weeks' duration. CLINICAL FINDINGS: The lameness was attributed to hypertrophic osteodystrophy. Portosystemic shunting was suspected on the basis of low serum albumin concentration and high serum bile acids concentration, and an intrahepatic shunt was identified ultrasono-graphically. Celiotomy was performed, and the shunt was partially closed with a cellophane band. During follow-up ultrasonography 7 months later, dilation of the left renal pelvis and proximal portion of the left ureter was identified. During exploratory celiotomy, the left ureter was found to pass dorsal to the caudal vena cava, and circumcaval ureter was diagnosed. TREATMENT AND OUTCOME: The ureter was transected, repositioned ventral to the vena cava, and anastomosed. Follow-up ultrasonographic examinations revealed gradual resolution of the hydronephrosis and hydroureter. CLINICAL RELEVANCE: Findings suggest that circumcaval ureter should be considered in the differential diagnosis for hydronephrosis and hydroureter in dogs. Partial obstruction of the middle segment of the ureter on ultrasonograms or contrast radiographs should increase the index of suspicion for this condition.     

Ultrasonographic findings in cows with dilatation, torsion and retroflexion of the caecum

Thirty cows with caecal dilatation underwent clinical and ultrasonographic examinations, followed by a right flank laparotomy and surgical correction. The intraoperative findings were compared with the results of the ultrasonographic examination. The appearance, position, dimensions, diameter and nature of the contents of the caecum and proximal and spiral ansa of the colon were determined with a 3.5 MHz linear transducer. The wall of the proximal ansa of the colon and of the dilated caecum closest to the abdominal wall was visible in all the cows and appeared as an echogenic semicircular line immediately adjacent to the peritoneum. The contents of the caecum and of the proximal and spiral ansa of the colon were not visible in 21, 25 and 25 cows, respectively, owing to gas. In the remaining cows, the contents were hypoechogenic to echogenic in appearance. In all of the cows, the dilated caecum was imaged from the right abdominal wall at the level of the tuber coxae. The caecum was imaged from the 12th, 11th and 10th intercostal spaces in 11, five and three cows, respectively. The caecum and proximal ansa of the colon were situated immediately adjacent to the right abdominal wall in 28 cows, but in the other two cows parts of these structures were pushed away from the abdominal wall by the liver or gall bladder. The diameter of the caecum, measured at various sites varied from 7.0 to 25.0 cm. Caecal dilatation was diagnosed on the basis of the results of rectal examinations in 28 of the cows, but in all 30 cows on the basis of the results of the ultrasonographic examinations. Dilatation and caudal displacement of the caecum were diagnosed in 18 cows; dilatation and cranioventral retroflexion of the caecum were diagnosed in six cows, and dilatation and craniodorsal retroflexion of the caecum were diagnosed in two cows. In the four other cows, the direction of the retroflexed caecum could not be determined. The diagnosis of caecal dilatation based on the ultrasonographic findings was confirmed in all the cows during exploratory laparotomy. The results of ultrasonography and exploratory surgery with regard to the position of the dilated and sometimes retroflexed or twisted caecum were in complete agreement in 18 cases, in partial agreement in eight cases, but in four cases did not agree.     

Acute gaseous peritonitis after rupture of a retroperitoneal rectal diverticulum in a dog

An 11-year-old, entire male coton de tulear was presented on emergency with acute and severe depression, acute abdominal pain and vomiting of 24 hours duration. Historical complaints included right perineal swelling, dyschezia and tenesmus of 18 months duration. Abdominal ultrasonography and radiography suggested a pneumoperitoneum and positive-contrast colonography showed leakage of contrast medium into the caudal abdomen and the presence of a large retroperitoneal pouch. Exploratory laparotomy allowed the visualisation of faecal leakage from the retroperitoneal space into the peritoneal cavity. Using a perineal approach, a large necrotised rectal diverticulum filled with faeces was found over the retroperitoneal structures. A standard herniorrhaphy was then performed. The dog recovered uneventfully and dyschezia did not recur at the nine month follow-up. Rectal diverticulum rupture associated with peritonitis has not been described in the veterinary literature, to the authors' knowledge, and should be considered as a rare differential diagnosis in dogs being presented with gaseous peritonitis.     

Retroperitoneal perirenal pseudocyst in a Massese breed ram.

The macroscopic and microscopic features of a retroperitoneal perirenal pseudocyst in a 12-month-old ram without impairment of renal function are described. In humans and animals, uriniferous pseudocysts may be of traumatic origin, resulting from rupture of kidney, renal pelvis, or ureter, or congenital. Lymphatic pseudocysts may develop secondary to inflammatory obstruction of the hilar lymphatics after perinephritis or renal transplantation. In this case, histologic characteristics of the pseudocyst wall were suggestive of development from the parietal peritoneal layer encapsulating the kidney. This is the first case of retroperitoneal perirenal pseudocyst in a sheep.     

URINOMA (PARA-URETERAL PSEUDOCYST) IN A DOG

A urinoma is an encapsulated extravasation of urine. In this case history report, the radiographic and ultrasonographic features of a urinoma in a dog are described. The dog presented with a palpable mass in the right flank which developed following ovariohysterectomy. Urinoma was considered when ultrasonographically, a sharply marginated, anechoic mass immediately caudal to the right kidney, ipsilateral hydroureter and hydronephrosis were detected. Extravasation of contrast medium was not seen during excretory urography. A fluid-filled retroperitoneal mass adjacent to a transected ureter was found at exploratory laparotomy. The diagnosis of urinoma (para-ureteral pseudocyst) and hydronephrosis was confirmed histopathologically.     

COMPARISON BETWEEN ULTRASONOGRAPHIC AND CLINICAL FINDINGS IN 43 DOGS WITH GALLBLADDER MUCOCELES

Cholecystectomy is the current standard recommended treatment for dogs with gallbladder mucoceles. However, medical management with monitoring has also been recommended for asymptomatic dogs. The purpose of this retrospective study was to compare ultrasonographic patterns of gallbladder mucoceles with clinical disease status in a group of dogs. For each included dog, the ultrasonographic pattern of the mucocele was classified into one of six types: type 1, immobile echogenic bile; type 2, incomplete stellate pattern; type 3, typical stellate pattern; type 4, kiwi like pattern and stellate combination; type 5, kiwi like pattern with residual central echogenic bile; and type 6, kiwi like pattern. A total of 43 dogs were included. Twenty‐four dogs, including 11 dogs with gallbladder rupture, were symptomatic. Nineteen dogs were asymptomatic. Cholecystectomy (n = 19), medical therapy (n = 17), or monitoring (n = 6) treatments were applied according to clinical signs and owners’ requests. One dog suspected of having gallbladder rupture was euthanized. Frequencies of gallbladder mucocele patterns were as follows: type 1 = 10 (23%), type 2 = 13 (30%), type 3 = 5 (12%), type 4 = 11 (26%), type 5 = 4 (9%), and type 6 = 0. In dogs with gallbladder rupture, type 2 (8/13) was the most common. No significant correlations were found between ultrasonographic patterns of gallbladder mucoceles and clinical disease status or gallbladder rupture. Findings indicated that ultrasonographic patterns of gallbladder mucoceles may not be valid bases for treatment recommendations in dogs.     

PERIRENAL EFFUSION IN DOGS AND CATS WITH ACUTE RENAL FAILURE

Perirenal fluid accumulation has been described as an ultrasonographic feature of urine leakage, hemorrhage, abscessation, or neoplasia. The purpose of this retrospective study was to report perirenal effusion as an additional ultrasonographic finding in canine and feline patients with acute renal failure. The causes of acute renal failure in 18 patients included nephrotoxicity (4), leptospirosis (3), ureteral obstruction (2), renal lymphoma (2), ureteronephrolithiasis (2), prostatic urethral obstruction (1) and interstitial nephritis and ureteritis (1). An underlying cause was not identified in three patients. The sonographic finding of perirenal fluid was bilateral in 15 patients. Unilateral perirenal fluid was identified ipsilateral to the site of ureteric obstruction in two patients. Large effusions extended into the caudal retroperitoneal space. Additional sonographic findings suggestive of renal parenchymal disease included mild (5), moderate (5) or severe (2) pyelectasia, increased renal echogenicity (11), increased (9) or decreased renal size (2) and ureteral and/or renal calculi (3). There did not appear to be an association between the volume of perirenal fluid and the severity of renal dysfunction. All patients with large effusions underwent euthanasia. Perirenal fluid developing in acute renal failure is thought to be an ultrafiltrate associated with tubular back-leak into the renal interstitium that overwhelms lymphatic drainage within the perirenal and retroperitoneal connective tissues although obstruction to urine flow may also play a role. Localized perirenal retroperitoneal free fluid may be a useful ultrasonographic feature to assist with the characterization of, and determination of prognosis in, patients with suspected renal disease.     

Ultrasonographic differentiation between portal venous and parenchymal gas may be important for the prognosis of canine and feline hepatic emphysema: 37 cases

The aim of this retrospective, cross‐sectional, study was to evaluate clinical findings and outcomes for different ultrasonographic patterns of hepatic emphysema in dogs and cats. Dogs and cats with an ultrasonographic diagnosis of hepatic emphysema and a known outcome, from January 2010 to January 2018, were enrolled. The following data were recorded from medical and ultrasonographic records: ultrasonographic patterns of hepatic emphysema (parenchymal, portal venous, biliary), clinical signs, laboratory findings, and outcomes (favorable, poor). A total of 33 dogs and four cats met the inclusion criteria. Among these, 23 cases were classified as hepatic portal venous gas, 10 as parenchymal emphysema, and four as biliary emphysema. Clinical diagnosis categories were as follows: infection/sepsis (9), gastro‐intestinal disease (9), iatrogenic (9), trauma (5), and liver neoplasia (5). An increase in serum liver enzymes was significantly associated with parenchymal emphysema (P = .03). Other clinical and laboratory findings were not associated with the type of hepatic emphysema. Hepatic portal venous gas was mostly transient in patients with ultrasonographic follow‐up. The overall mortality was 40.5%. A significant difference was found between mortality by portal venous gas (21.7%) and mortality by parenchymal emphysema (90%) (P = .003). In conclusion, the ultrasonographic differentiation of hepatic emphysema between hepatic portal venous gas and parenchymal emphysema may be important for the prognosis of hepatic emphysema. The presence of parenchymal emphysema may be a poor prognostic indicator, while hepatic portal venous gas may be more benign. However, ultrasound findings should be carefully evaluated in the context of clinical findings.     

MICRONODULAR ULTRASOUND LESIONS IN THE COLONIC SUBMUCOSA OF 42 DOGS AND 14 CATS

Micronodular ultrasound lesions have been detected in the colonic submucosa of dogs and cats at our hospital. The lesions had rounded/oval shapes, measured 1–3 mm in size, and exhibited a hypo/anechoic ultrasonographic pattern. To our knowledge, these lesions have not been previously reported in human or veterinary patients. The purpose of this retrospective study was to determine whether micronodular lesions were associated with other abdominal ultrasound abnormalities or clinical findings. Medical records of dogs and cats with sonographic reports describing micronodular lesions within the colonic submucosa were reviewed. Concurrent ultrasonographic abnormalities were recorded and compared with clinical sidgns and follow‐up data. A total of 42 dogs and 14 cats met inclusion criteria. Concurrent sonographic abnormalities included the following: increased colon wall thickness (12.5%); small bowel wall thickening, altered layering, and/or hyperechoic mucosa (45%); abdominal effusion (29%); caudal mesenteric lymphadenopathy (46%); mesenteric lymphadenopathy (27%); and pericolic peritoneal fat reactivity (9%). Fifty of 56 animals presented with diarrhea. Twenty‐seven cases had clinical signs of colitis and ultrasonographic lesions were limited to the colonic submucosa. In nine cases, follow‐up examination at 6–8 weeks showed resolution of clinical and ultrasonographic signs. Ultrasonographic and clinical examinations in 17 patients at 12–18 months and in 20 patients at 18–30 months from initial diagnosis showed resolution of submucosal lesions and clinical signs of enteropathy. The authors propose that micronodular submucosal ultrasound lesions may represent reactive intraparietal lymphoid follicles and may be indicators of colonic inflammatory diseases in dogs and cats.