The use of endoscopy-assisted nephrolithotomy for unilateral nephrolith removal in a rabbit (Oryctolagus cuniculus).

A 3-year-old spayed female rabbit (Oryctolagus cuniculus) was referred with mineralizations in the left kidney. Despite medical management, 8 months after the initial examination, a 5.3-mm obstructive nephrolith with dilatation of the renal diverticuli was observed with abdominal ultrasonography. Surgical removal by endoscopy-assisted nephrolithotomy was completed. A flexible endoscope was introduced into the renal pelvis through a puncture incision in the lateral aspect of the kidney. The nephrolith was removed with endoscopic grasping forceps through the same orifice and the renal pelvis and diverticula were flushed to extract the smaller mineralized particles. The nephrotomy site was closed and the kidney was sutured to the abdominal wall. The rabbit recovered uneventfully. Six months after surgery, a non-obstructive stone was identified; however, 2 years later the rabbit remains asymptomatic. To the authors' knowledge, this is the first report on the use of endoscopy-assisted nephrolithotomy to extract a complicated nephrolith in a rabbit.

L'utilisation de la néphrolithotomie assistée par endoscopie pour l'élimination unilatérale des néphrolithes chez un lapin ( Oryctolagus cuniculus ). Une lapine stérilisée de 3 ans (Oryctolagus cuniculus) a été référée avec des minéralisations dans le rein gauche. Malgré la prise en charge médicale, 8 mois après l'examen initial, un néphrolithe obstructif de 5,3 mm avec dilatation des diverticules rénaux a été observé à l'échographie abdominale. L'ablation chirurgicale par néphrolithotomie assistée par endoscopie a été réalisée. Un endoscope flexible a été introduit dans le pelvis rénal par une incision de ponction dans la face latérale du rein. Le néphrolithe a été retiré avec une pince à préhension endoscopique par le même orifice et le bassinet et les diverticules rénaux ont été rincés pour extraire les plus petites particules minéralisées. Le site de néphrotomie a été fermé et le rein a été suturé à la paroi abdominale. Le lapin a récupéré sans incident. Six mois après la chirurgie, une pierre non obstructive a été identifiée; cependant, 2 ans plus tard, le lapin reste asymptomatique. À la connaissance des auteurs, il s'agit du premier rapport sur l'utilisation de la néphrolithotomie assistée par endoscopie pour extraire un néphrolithe compliqué chez un lapin.(Traduit par Dr Serge Messier).

Ureteropyeloscopic removal of a nephrolith from a 19 year old Hanoverian gelding.

OBJECTIVE: To describe the ureteropyeloscopic removal of a nephrolith in a horse. ANIMALS: A 19 year old Hanoverian gelding with history of urolithiasis requiring surgical intervention. STUDY DESIGN: Case report METHODS: The horse presented with signs of abdominal straining and stranguria. A proximal urethral calculus was palpable externally within the perineal urethra. Perineal urethrostomy (PU) at the location of the urethral calculi was performed to remove the urethral obstruction. Left nephrolithiasis was then treated by endoscopic retrieval, inserting the endoscope through the PU. The procedures were performed over 2 consecutive days, with the horse standing and sedated. Medical therapy included antimicrobial and anti-inflammatory treatment. RESULTS: The ureteropyeloscopic removal of a nephrolith from the left renal pelvis was completed. No complications were appreciated following the procedure, and the horse was able to return to athletic activity within 2 weeks. The horse had no further clinical signs referable to urinary dysfunction 7 months later. CONCLUSION: Ureteropyeloscopic removal of a nephrolith from the renal pelvis is technically feasible in the equine patient and preserves function of the affected kidney. The availability of a treatment that maintains renal function is a distinct benefit over unilateral nephrectomy, particularly when treating a condition that frequently involves both kidneys.

Management of nephrolithiasis by pyelotomy and pyeloscopy in an Asian small-clawed otter (Aonyx cinereus).

CASE DESCRIPTION: A captive adult sexually intact female Asian small-clawed otter (Aonyx cinereus) was evaluated because of diarrhea and signs of abdominal discomfort on arrival at the quarantine area of a zoological park. CLINICAL FINDINGS: Radiographic and ultrasonographic examinations revealed the presence of a large nephrolith in the left kidney. Mild nephrolithiasis was detected in the right kidney. Results of hematologic and serum biochemical analyses were within references intervals. Intravenous pyelography was used for functional assessment of the urinary system and revealed normal renal excretory function bilaterally. TREATMENT AND OUTCOME: Unilateral (left-sided) pyelotomy was selected as a treatment option to preserve maximal functional renal tissue. Pyeloscopy was successfully used for detection of some small nephroliths that were not removed by repeated flushing of the renal pelvis. Surgical treatment of the right kidney was not considered necessary. The otter recovered fully from anesthesia and surgery. Renal function was considered normal when assessed at 3 and 7 days and at 1 and 12 months after surgery. CLINICAL RELEVANCE: To the authors' knowledge, pyelonephrotomy in otters has not been reported and may be considered as a potential surgical solution for nephrolithiasis. Pyeloscopy allowed the identification of small uroliths that were not removed by repeated flushing of the left renal pelvis following removal of the large nephroliths.

Lateral approach to nephrotomy in the management of unilateral renal calculi in a rabbit (Oryctolagus cuniculus).

CASE DESCRIPTION: A 5-year-old 2.23-kg (4.91-lb) spayed female Lop rabbit (Oryctolagus cuniculus) was evaluated because of a history of lethargy, polyuria, and polydipsia of 1 month's duration. The referring veterinarian made a presumptive diagnosis of hypercalcemia of unknown etiology on the basis of a plasma total calcium concentration of 14.0 mg/dL. CLINICAL FINDINGS: Physical examination findings were unremarkable. Hematologic and plasma biochemical analysis revealed nonregenerative, normocytic, normochromic anemia (PCV, 28%) with heteropenia (23%; 1,334 heterophils/mL) and a total plasma calcium concentration of 16 mg/dL. Radiographic and ultrasonographic examination revealed radiodense and hyperechoic structures in both renal pelves and right unilateral nephrolithiasis. TREATMENT AND OUTCOME: Nephrotomy was performed via laparotomy with a right lateral approach. A nephrolith composed of calcium carbonate and carbonate apatite was removed from the right renal pelvis. The rabbit's plasma tested positive for antibodies against Encephalitozoon cuniculi by means of an indirect immunofluorescence assay, and fenbendazole (20 mg/kg [9.1 mg/lb], p.o., q 24 h) was administered for 28 days. Although plasma calcium concentration was not substantially decreased after treatment (values were 14.1 and 15.1 mg/dL 1 week and 3 months after surgery, respectively), the patient did not have clinical signs of hypercalcemia and died of unrelated causes approximately 1 year after surgery. CLINICAL RELEVANCE: To the authors' knowledge, this is the first report of a nephrotomy performed in a rabbit via a lateral abdominal approach. This approach allowed easy location of the kidney and also reduced manipulation, thus decreasing the risk of damaging the abdominal viscera and potentially decreasing postoperative pain.

Urolitíase em 76 cães / Urolithiasis in 76 dogs

Entre janeiro de 1990 e dezembro de 2010 foram necropsiados 4.872 cães no Laboratório de Patologia Veterinária da Universidade Federal de Santa Maria (LPV-UFSM). Destes, 76 (1,6%) apresentaram urólitos em algum local do sistema urinário. O perfil epidemiológico dos cães afetados demonstrou o predomínio de machos (64,5%), adultos (52,6%) e com raça definida (56,6%). Sinais clínicos indicativos de urolitíase foram reportados em 30,3% dos casos e consistiram principalmente de hematúria, anúria, disúria e incontinência urinária. Os urólitos tiveram localização única ou múltipla e os locais anatômicos mais frequentemente acometimentos, em ordem decrescente de frequência, foram: bexiga, rim e uretra. Urolitíase ureteral não foi observada. Lesões secundárias à urolitíase foram observadas em aproximadamente 40% dos cães afetados; as mais prevalentes, em ordem decrescente de frequência, foram: cistite, obstrução uretral, hidroureter, hidronefrose, ruptura vesical (com uroperitônio) e pielonefrite. Em 25% dos cães afetados ocorreu morte espontânea ou eutanásia decorrente das lesões secundárias à urolitíase. Lesões extra-renais de uremia foram observadas em 11,8% dos casos.

From January 1990 to December 2010, 4,872 dogs were necropsied at the Laboratório de Patologia Veterinária, Universidade Federal de Santa Maria. Seventy six dogs (1.6%) had uroliths along the urinary tract. The epidemiological profile of the affected dogs showed predominance of males (64.5%); adults (52.6%); and pure breeds (56.6%). Clinical signs suggestive of urolithiasis were reported in 30.3% of the dogs and consisted mainly of hematuria, anuria, dysuria and urinary incontinency. The uroliths were found in one or more anatomical sites, and the main affected ones (in descending order) were urinary bladder, kidney, and urethra. Ureteral urolithiasis was not observed. Secondary lesions to urolithiasis were found in about 40% of the cases. The most prevalent (in descending order) were cystitis, urethral obstruction, hydroureter, hydronephrosis, urinary bladder rupture (with uroperitoneum), and pyelonephritis. In 25% of the affected dogs, spontaneous death occurred or euthanasia was performed due to the secondary lesions of urolithiasis. Extra-renal lesions of uremia were found in 11.8% of the cases.

Impact of a high-phosphorus diet on the sonographic and CT appearance of kidneys in degus, and possible concurrence with dental problems.

The main aim of this study was to investigate the impact of pelleted diet of different mineral composition on the sonographic and CT appearance of kidneys in degus (Octodon degus). A total of 35 animals were randomly divided into five groups, fed diets containing different calcium and phosphorus contents (13.5 g/kg calcium and 6.3 g/kg phosphorus, or 9.1 g/kg calcium and 9.5 g/kg phosphorus) and given different amounts of exposure to UV light. Endoscopic examination of the oral cavity as well as renal ultrasonography and CT was performed four times at four-month intervals throughout the study. After 14 months of feeding an experimental diet, all degus were euthanased and subsequently all kidneys were collected for histopathological examination. Animals fed a diet with high dietary phosphate and improper calcium to phosphorus ratio showed severe nephrocalcinosis. Ultrasonographic and CT kidney abnormalities presented as hyperechogenicity and hyperdensity (interpreted as nephrocalcinosis), respectively. The most striking changes were seen at the corticomedullary zone. Ultrasonography and CT correlated in all cases with histopathological findings. Dental disease developed quickly in groups fed diets with an improper calcium and phosphorus content, with obvious apical and coronal elongation of all the teeth. A possible influence of UV light access could not be proved in this study.

Urolithiasis and transitional cell carcinoma of the bladder in a Wistar rat.

Urolithiasis and carcinoma of the urinary bladder are generally uncommon in rats. In particular, spontaneous urolithiasis and carcinoma of the bladder in young rats has not yet been reported. Our case concerns the unexpected finding of urolithiasis of the bladder and left kidney of an apparently healthy 4-mo-old male Wistar rat. The bladder was filled with 28 white, round to oval calculi of various sizes. The kidney presented a single unevenly shaped calculus in the pelvis. Histology revealed, in addition to urolithiasis, a grade II papillary transitional cell carcinoma of the bladder, with muscle invasion and neoplastic extension to the left renal pelvic epithelium. No previous experimental procedure or dietetic manipulation had occurred, which could be held responsible for these findings. These unusual findings indicate that, unknown to researchers, unapparent factors can affect the health status of even relatively young experimental animals. Asymptomatic disease, such as the unknown presence of a tumor, potentially can affect many parameters and thus influence research results.

Left perinephric abscess associated with nephrolithiasis and bladder calculi in a bitch.

An eight-year-old, entire female Pekingese cross, weighing 3.8 kg, had been inappetent with fever, depression, abdominal pain, vomiting and diarrhoea for seven days. The radiographic and ultrasonographic findings were consistent with glomerulonephritis, nephrolithiasis in both kidneys, bladder calculi and an accumulation of fluid in the left perinephric space. The clinical signs, together with the results of the diagnostic imaging, suggested that this fluid could be pus. A definitive diagnosis of a subcapsular abscess in the left kidney was established when this kidney was removed surgically. A histopathological examination of the kidney revealed a diffuse suppurative interstitial nephritis, membranous glomerulonephritis and an abscess invading the perinephric adipose tissue from the renal cortex. Twelve months after surgery the dog remains clinically stable, but owing to the disease of its remaining kidney its long-term prognosis is poor.

An investigation into the effects of storage on the diagnosis of crystalluria in cats.

Urinalysis was performed on 41 cats with no history of urinary tract disease. Samples were divided into aliquots, stored under differing condition and then examined for the presence of crystalluria. Crystalluria was detected in at least one stored sample in 92% of cats fed a mixed wet/dry food diet compared to 24% in the fresh sample. Crystalluria was not detected in any sample or aliquot from cats fed all wet food diets.

Chronic renal failure associated with nephrolithiasis, ureterolithiasis, and renal dysplasia in a 2-year-old quarter horse gelding.

A 2-year-old quarter horse gelding presented for evaluation of polyuria and polydipsia. Azotemia was detected on serum chemistry profile. Small, misshapen, hyperechoic kidneys with decreased corticomedullary demarcation, hydronephrosis, and a right nephrolith were noted ultrasonographically. The diagnosis of end-stage kidney disease and dysplasia was made histopathologically using ultrasound-guided biopsy. Two ureteroliths were found in the right ureter via cystoscopy, and a nephrolith was seen in the right kidney at necropsy. Clinical, ultrasonographic, and pathologic features of equine urolithiasis and renal dysplasia are discussed.

Canine and feline nephrolithiasis. Epidemiology, detection, and management.

Calcium oxalate (39%) and struvite (33%) were the predominant mineral types in canine nephroliths submitted to the Minnesota Urolith Center. Urate salts (12%) and calcium phosphate (2%) occurred less frequently. Provided they are not causing obstruction, struvite nephroliths may be dissolved with medical protocols. Although there are no dissolution protocols for nephroliths containing calcium, risk-benefit ratios should be considered before proceeding with surgery.

Dry extracorporeal shock wave lithotripsy for treatment of ureterolithiasis and nephrolithiasis in a dog.

A second-generation lithotriptor was used to perform dry extracorporeal shock wave lithotripsy in a dog with ureterolithiasis, nephrolithiasis, and chronic renal failure. Previous studies on the use of lithotripsy in dogs have involved first-generation machines and have primarily concentrated on acute and chronic effects of lithotripsy in experimental models. Treatment in this dog resulted in resolution of ureteral obstruction, ureterolithiasis, and nephrolithiasis, and avoided complications associated with ureteral and renal surgery. The only complication was substantial hematuria of 12 hours' duration immediately after the procedure. Second-generation lithotripsy may offer an effective treatment for ureterolithiasis or nephrolithiasis in selected dogs.

Influence of magnesium, water, and sodium chloride on urolithiasis in veal calves.

Forty veal calves were fed milk replacers containing differing concentrations of Mg in a 16-w study. The concentrations were .1% (basal), .3%, .6% Mg, and .6% Mg plus 2% NaCl. The four groups were further subdivided into two groups fed reconstituted milk replacer at 14 or 17.9% DM. Weight gain was greater at the two lower concentrations of Mg. Calves fed .6% Mg or .6% Mg plus NaCl excreted significantly more Mg than calves fed .1 or .3% magnesium. The low water group (17.9% DM) excreted a more concentrated urine relative to Mg, Ca, and P than did the high water group (14% DM). No urethral obstructions were observed. Seventy percent of calves at .6% Mg and 30% of calves at .6% Mg plus NaCl had stones in their kidneys consisting primarily of calcium apatite and secondarily of struvite. Added NaCl reduced kidney and bladder calculi formation. When high amounts of water were fed, added NaCl prevented calculi formation completely. All calves fed the NRC level of .1% Mg performed normally.

Percutaneous nephrolithotomy in the dog. An experimental study.

Percutaneous nephrostomies (PN) were created with teflon fascial dilators under fluoroscopic guidance, to implant stones bilaterally into the renal pelves of five dogs weighing 7 to 35 kg. Between one and seven stones of 0.25 to 1.00 cm diameter were implanted into each renal pelvis. Two to 4 weeks later, PN tracts were recreated, and the implanted renal stones were successfully removed under fluoroscopic and endoscopic visualization. Results of gross and histopathologic evaluation of the kidneys 2, 7, 14, 30, and 90 days after stone removal showed minimal, localized renal parenchymal trauma. Complications, although infrequent, included proximal ureteral tears and hemorrhage. Difficulty was encountered in maneuvering equipment around large or numerous stones. Canine percutaneous nephrolithotomy was successful despite great variation in kidney size, as well as variations in the number, size, and shape of stones in the upper urinary tract.

Crystalline composition of equine urinary calculi.

X-ray diffraction crystallography was used to determine the crystalline composition of 18 equine urinary calculi, including stones originating in the kidney, bladder and urethra. Calcium carbonate in the form of calcite was found to be the major component in all calculi examined. Other components commonly found included weddellite and substituted vaterite. Urine deposits from a number of normal horses were also examined. The significance of these findings, as well as those from a number of previous reports, are discussed in relation to the possible aetiology of urolithiasis in the horse.

Diseases of the kidneys.

Ultrasound examination offers important diagnostic and prognostic information in renal disease of the horse. Differentiation between acute nephrosis and chronic renal disease can usually be made because of the advanced degree of morphologic change usually prevalent in chronic conditions. Dilatations of the recesses and pelvis (hydronephrosis) as well as the relative thickness of the renal cortex and medulla are readily determined. Mineral densities (calculi) are recognizable by their characteristic acoustic shadowing.