Progressive urethral dilation in male horses undergoing perineal urethrotomy for cystolith removal: 22 cases.

This retrospective case series describes the use of progressive urethral dilation in 22 client-owned male horses undergoing perineal urethrotomy (PU) for cystolith removal. Medical records of horses undergoing PU and urethral dilation for treatment of cystolithiasis were reviewed. Dilation of the pelvic urethra was performed following PU and using customized dilators with the same length (30cm) and with various outer diameters (25 to 45mm). Analyzed data included: signalment, cystolith size, renal ultrasound findings, method used for cystolith removal, diameter of urethral dilators, intra- and post-operative complications, and hospitalization time. Cystolith size ranged between 37mm and 90mm. Dilation of the pelvic urethra was as follows: 35mm (n=8), 25mm (n=6), 39mm (n=3), 33mm (n=2), 28mm (n=2) and 45mm (n=1). In 6 cases, the cystolith was removed without fragmentation. In the remaining 16 horses, lithotripsy was performed with forceps (n=9) or a pneumatic scaler (n=7). In 15 horses a retrieval device was used to aid in calculi removal. Hospitalization time ranged between 1 and 5 days. Intra-operative complications occurred in one horse. No post-operative complications were recorded. Follow-up information was available for 21 horses (range 1-8 years). Urethral dilation via PU may be a viable option for cystolith removal in male horses.

Pseudomembranous cystitis in cats with presumed or confirmed mineralization: A retrospective study of 26 cases (2016-2021).

BACKGROUND: Pseudomembranous cystitis (PMC) in cats is a recognized disease, but concurrent mineralization is reported rarely and its outcome is poorly described. HYPOTHESIS AND OBJECTIVES: Describe a population of cats with PMC and the prevalence of concurrent mineralization. ANIMALS: Twenty-six cats with PMC. METHODS: Medical records were retrospectively reviewed (January 2016 to December 2021). Cats with an ultrasound diagnosis of PMC were included. Clinicopathologic results, imaging, treatment, and outcome were reviewed. RESULTS: All cats were male and 21 (80%) were diagnosed with urethral obstruction (UO). Five cats (23.8%) had positive urine culture (Staphylococcus felis, 3/5; Proteus mirabilis, 2/5) with a median urine pH of 8 (range, 6-9). All cats had ultrasonographic changes suggestive of mineralization. On ultrasound examination, 10 cats (38.5%) had pseudomembranes with acoustic shadowing suggestive of mineralization, 15 (57.7%) had changes indicative of ulceration, and 8 (31%) had changes compatible with of a urachal anomaly. Twenty-two cats received medical treatment, 4 underwent surgery (3 percutaneous cystolithotomy, 1 cystotomy). Twenty cats (77%) survived to discharge. Follow-up ultrasound examination indicated resolution of PMC in 6/7 cats, 4 had persistent hyperechoic bladder lining. Five of 12 cats with follow-up had a relapse of lower urinary tract signs. CONCLUSIONS AND CLINICAL IMPORTANCE: Pseudomembranous cystitis was diagnosed mainly in male cats with UO and imaging findings suggestive of mineralization were present in all cases. Frequent negative urine culture suggests a different etiology than encrusting cystitis related to urease-positive bacteria. Good outcomes can be achieved with medical management.

Comparison of percutaneous cystolithotomy and open cystotomy for removal of urethral and bladder uroliths in dogs: Retrospective study of 81 cases (2014-2018).

OBJECTIVE: Compare percutaneous cystolithotomy (PCCL) and open cystotomy (OC) for removal of bladder and urethral uroliths. DESIGN: Retrospective study. ANIMALS: Client-owned dogs and cats that underwent PCCL (n = 41) or OC (n = 40) between January 1, 2014 and February 28, 2018 at a referral center. METHODS: Medical records of dogs and cats that underwent a PCCL or an OC were reviewed. History, signalment, physical examination, diagnostic tests, length of the procedure and anesthesia, complications, and duration of hospitalization were recorded. RESULTS: A total 17 cats (PCCL = 10; OC = 7) and 64 dogs (PCCL = 31; OC = 33) were included. There was no significant difference, regardless of species, in the mean surgical time (45 min [24-160 min] and 48.5 min [15-122 min] with P = .54 in dogs, P = .65 in cats) nor mean duration of anesthesia (90 min [50-120 min] and 98 min [54-223 min] with P = .87 in dogs, P = .08 in cats) in the PCCL and OC groups respectively. Number of uroliths did not affect duration of surgery in either group. Complete urolith removal was achieved in 98% of dogs and cats in both groups. The median hospitalization time was significantly shorter in the PCCL group for dogs (11.3 hours [range 4 to 51.3] in the PCCL vs 56.6 hours [range 7.3 to 96] in the OC group; P < .001) but did not differ for cats (24.5 hours [range 8.3 to 30] in the PCCL vs 56.6 hours [range 10.1 to 193.2] in the OC group; P = .08). CONCLUSION AND CLINICAL RELEVANCE: Bladder urolith removal by PCCL procedure is no longer than OC. Further studies are needed to compare the pain related to procedure between PCCL and OC.

Small ruminant urinary obstruction: decision trees for treatment.

Urolithiasis is the most common cause of urinary tract disease in small ruminants and has significant economic and production impacts worldwide. Urolithiasis is multifactorial in origin and generally begins with the formation of cystoliths followed by urethral obstruction. The condition is most common in males. Clinical signs are variable depending on the severity of the obstruction. Uroliths can be calcium, struvite, or silicate based; however, struvite and amorphous magnesium calcium phosphate are the most common urolith types observed in small ruminants. Although urethral process (vermiform appendage) amputation is widely considered the first line of treatment, reobstruction is common within the first 36 hours. Surgical interventions such as temporary tube cystostomy, perineal urethrostomy (PU), modified proximal perineal urethrostomy, vesico-preputial anastomosis (VPA), and urinary bladder marsupialization (BM) are reported to carry an improved prognosis for long-term survival. PU carries a lower proportion of long-term success (> 12-month survival time) when compared with VPA and BM. Stoma stricture and urine scald are the most commonly observed surgical complications. Currently, the literature provides minimal direction for clinician decision-making in managing these cases while accounting for patient history, client financial ability, composition of calculi, and potential treatment complications. Small ruminant urinary obstructions are challenging and complicated conditions to treat, due to their multifactorial etiology, ruminant urogenital anatomy, and the variety of imperfect treatment options available. The purpose of this article this article is to provide veterinary practitioners with decision trees to guide management and treatment of urolithiasis in small ruminants.

Bladder wall adhesion causing a vesicular septum in a dog following surgical cystotomy.

CASE DESCRIPTION: An 8-year-old spayed female Yorkshire Terrier-Poodle dog was evaluated for persistent pollakiuria and stranguria following routine cystotomy for calcium oxalate cystoliths. CLINICAL FINDINGS: The dog presented for a cystotomy with intermittent hematuria. Postoperative radiographs revealed no remaining cystoliths. Urine, cystolith, and bladder mucosal aerobic cultures were negative. Pollakiuria, stranguria, and hematuria developed immediately after surgery and persisted despite antibiotics. Ultrasound revealed suspected fibrous adhesions within the urinary bladder lumen connecting the dorsal and ventral bladder wall creating a septum. This was confirmed cystoscopically 4 weeks after surgery. TREATMENT AND OUTCOME: Cystoscopic-guided laser ablation was performed to incise abnormal tissue connecting the ventral and dorsal bladder wall using a holmium:yttrium-aluminum-garnet laser. Three weeks later, ultrasound revealed adhesion resolution though mild pollakiuria and stranguria persisted. Oxybutynin was prescribed and clinical signs resolved. At 27 months after ablation, hematuria occurred with recurrent cystoliths. These cystoliths were removed by percutaneous cystolithotomy, documenting a cystoscopically normal bladder wall. The patient had normal urination for 55.5 months after ablation, with normal bladder wall thickness on ultrasound repeated at 27 and 36 months after ablation. CLINICAL RELEVANCE: To the authors' knowledge, an adhesion creating a septum between the dorsal and ventral bladder wall has not been previously reported as a complication after cystotomy in any species and should be considered as a cause of persistent lower urinary signs after surgery. Ultrasound identified the lesion in this dog. Because bladder abnormalities can develop quickly after surgery, ultrasound might be considered if urine testing is not supportive of infection. Cystoscopic-guided laser ablation was a successful minimally invasive treatment in this case.

Efficacy of medical dissolution for suspected struvite cystoliths in dogs.

BACKGROUND: Medical dissolution of struvite uroliths in dogs is commonly recommended, but data on success rates and complications are limited. OBJECTIVES: To evaluate the efficacy of medical dissolution for suspected struvite cystoliths in dogs. ANIMALS: Fifty client-owned dogs fed a therapeutic dissolution diet, with or without administration of antimicrobials, for treatment of suspected struvite cystoliths. METHODS: Single institution, retrospective case series. Medical records were reviewed for dogs with at least 1 follow-up visit. Dissolution success, complications, and possible predictors of success were evaluated. RESULTS: Full dissolution of cystoliths was achieved in 58% (29/50) of dogs within a median of 35 days (range, 13-167). Of 21 dogs without success, 7 each had partial dissolution, no dissolution, or undetermined outcome. Uroliths containing >10% nonstruvite mineral were common in the nonsuccess group (11/16 analyzed). Maximum urolith diameter, number of uroliths, and baseline urine pH did not differ significantly between dogs with and without success. Dissolution was more likely in dogs receiving antimicrobial therapy (OR = 16.3, 95% confidence interval 1.9-787.4, P = .002). Adverse events occurred in 9 dogs (18%); urethral obstructions were the most common, but 3 of 4 dogs with this complication were obstructed on presentation, before trial initiation. CONCLUSIONS AND CLINICAL IMPORTANCE: Results support a medical dissolution trial for dogs with suspected struvite cystoliths. If no reduction in urolith size or number occurs by 1 month, a nonstruvite composition is likely, and alternative interventions should be considered. Dogs presenting with urethral obstructions should not be considered candidates for medical dissolution.

Effect of a struvite dissolution diet in cats with naturally occurring struvite urolithiasis.

OBJECTIVES: The aim of the study was to determine the efficacy of the low struvite relative supersaturation diet in dissolution of feline struvite cystoliths. METHODS: This was a prospective, open-label, two-center study. Twelve client-owned cats were enrolled based on the radiographic appearance of their uroliths and urinalysis parameters. Cats were fed the test diet exclusively for up to 56 days. Cats were radiographed every other week until radiographic evidence of dissolution occurred or the end of the study period was reached. Cats with radiographically apparent uroliths at the end of the study period underwent cystotomy for stone retrieval and analysis. RESULTS: Nine of the 12 cats completed the study. Eight experienced radiographic dissolution; seven of these had complete dissolution within the first month of treatment. One cat, whose owner declined cystotomy after partial dissolution at day 56, had complete radiographic resolution at 70 days of treatment. Two calcium oxalate urolith cores were removed from a cat that had partial radiographic dissolution. CONCLUSIONS AND RELEVANCE: The test diet was successful in dissolving suspected struvite cystoliths. As this diet is suitable for maintenance feeding of adult cats, it may be a suitable choice for long-term prevention of feline struvite urolithiasis.

The Use of Pneumatic Impact Lithotripsy in a Laparoscopic Retrieval Pouch for Removal of Large Cystoliths in Two Female Horses.

Two mares, aged 15 and 21 years, were examined because of urinary incontinence, intermittent hematuria, and urine scalding. On admission of both horses, physical parameters were within normal limits and urine scalding of the skin at the ventral perineum was noted. Transrectal palpation and cystoscopy revealed a large type I cystolith (>10 cm) with associated hyperemia and focal ulceration of the bladder mucosa. In horse 1, hemogram, serum biochemical analysis, and renal ultrasound were not performed because of owner finances. In horse 2, results from hematological and serum biochemical analysis were unremarkable and renal ultrasonography did not reveal any abnormalities. Pneumatic impact lithotripsy in a laparoscopic retrieval pouch was performed under cystoscopic guidance after caudal epidural anesthesia, with the horses standing and under sedation. A laparoscopic retrieval device was passed alongside a flexible endoscope into the urinary bladder and the cystolith was manipulated into the pouch. A customized single stainless-steel rod scaler attached to an air compressor was used for fragmentation of the cystolith contained within the retrieval pouch. Lithotripsy time was 42 minutes for horse 1 and 31 minutes for horse 2. Both horses were released from hospital the day of surgery. Both horses were continent and voided normal streams of urine for the duration of the follow-up periods of 27 and 19 months for horse 1 and horse 2, respectively. Pneumatic impact lithotripsy in a laparoscopic retrieval pouch provided a time-efficient and minimally invasive surgical treatment option for removal of large cystoliths in mares.

[Urolithiasis in a pet rat (Rattus norvegicus)]. / Urolithiais bei einer Heimtier-Ratte (Rattus norvegicus).

Uroliths are uncommon findings in rats. This report describes a case of a neutered male rat with dysuria due to an infectious cystitis as well as an urolith of the urinary bladder consisting of struvite and whewellit. Following cystotomy as well as treatment with antibiotics and analgetics the rat recovered rapidly.

Radiographic features of suspected suture-associated cystic calculi in dogs.

This retrospective case series describes the radiographic features of suspected suture-associated cystic calculi in six dogs with a history of at least one or multiple prior cystotomies. One of the dogs presented twice. Suspected suture-associated cystic calculi were multifocal, short, predominantly linear mineral opacities localized in the center of the urinary bladder on abdominal radiographs. One patient (n = 1) presented with multifocal round, pin point, and linear radiopaque calculi. The calculi were all calcium oxalate in composition. On gross examination, the calculi had a hollow center. Six cystotomies used monofilament absorbable suture material (polydioxanone [n = 4] or poliglecaprone 25 [n = 1]) in prior cystotomies. Suture material in two of the cases was unknown. Suspected suture-associated cystic calculi are a rare occurrence in veterinary medicine but should be considered in dogs that have a history of prior cystotomy, hollow core on gross analysis, and radiographic evidence of mineral opaque, predominantly linear, cystic calculi.

Removal of lower urinary tract stones by percutaneous cystolithotomy: 68 cases (2012-2017).

OBJECTIVE: To describe the use and outcome of percutaneous cystolithotomy (PCCL) for removal of urethral and bladder stones in dogs and cats. STUDY DESIGN: Retrospective case series. ANIMALS: Sixty-eight client-owned dogs and cats. METHODS: Records were reviewed and analyzed for dogs and cats that underwent PCCL between January 2012 and December 2017. Signalment, clinical presentation, laboratory and imaging data, procedure time, use of lithotripsy, biopsy, perioperative and immediate postoperative complications, hospitalization times, stone composition, and urine culture results were recorded. Owners were contacted by phone or email 3 weeks after the procedure. Follow-up communications with the owner and referring veterinarian were also recorded. RESULTS: Seventy percutaneous cystolithotomies were performed in 59 dogs and nine cats. The median duration of the procedure was 95 minutes (45-420), and lithotripsy was required in 3% (2/70) of PCCL. Complications during the procedure were reported in one case. In eighty-three percent of procedures (58/70), animals were discharged within 24 hours postoperative. Twenty-four percent (16/68) of animals had minor complications (lower urinary tract signs), and one dog had a major complication (surgical wound dehiscence) during the 3 weeks after the operation. Long-term follow-up revealed stone recurrence in 21% of cases followed more than a year after the procedure (7/33). CONCLUSION: Percutaneous cystolithotomy allowed removal of bladder and urethral stones with rapid postoperative recovery and few major perioperative or short-term postoperative complications. CLINICAL SIGNIFICANCE: Percutaneous cystolithotomy provides an attractive minimally invasive surgical alternative for removal of lower urinary tract stones in small animals.

Evaluation of a dry therapeutic urinary diet and concurrent administration of antimicrobials for struvite cystolith dissolution in dogs.

BACKGROUND: Struvite urolithiasis with bacterial urinary tract infection (UTI) is commonly reported in dogs; few data exist to describe successful dissolution protocols in dogs with naturally occurring disease. We hypothesized that a dry therapeutic urinary diet combined with targeted antimicrobial therapy can effectively dissolve presumptive struvite cystolithiasis in dogs with naturally occurring urease-producing bacterial UTI. RESULTS: Ten dogs with presumed infection-induced struvite cystolithiasis based on lower urinary tract signs (LUTS), radiodense cystoliths, and urease-producing bacterial UTI were enrolled. At enrollment, antimicrobials and dry therapeutic urinary diet were dispensed. In addition to lack of radiographic resolution of urolithiasis, dogs with persistent clinical signs were considered non-responders. There was no significant difference in pH between responders and non-responders; USG was significantly higher in the responder group. Recheck visits continued until radiographic dissolution or failure was documented. Five of the 10 dogs achieved radiographic dissolution of cystolithiasis within a median of 31 days (range 19-103). In the other 5 dogs, surgical urolith removal was necessary due to persistent LUTS (3 dogs within 2 weeks) or lack of continued dissolution noted radiographically (1 dog with numerous cystoliths failed at day 91; 1 dog failed by day 57 with questionable owner compliance). CONCLUSIONS: Dissolution of urinary tract infection induced struvite cystoliths can be accomplished in some dogs fed this dry therapeutic urinary diet in conjunction with antimicrobial therapy. Case selection could increase the likelihood of successful dissolution; however, if calcium phosphate is present, this could also prevent stone dissolution. If clinical signs persist despite diet and antimicrobials, stone removal is advised.

Associations of environment, health history, T-zone lymphoma, and T-zone-like cells of undetermined significance: A case-control study of aged Golden Retrievers.

BACKGROUND: T-zone lymphoma (TZL), an indolent disease in older dogs, comprises approximately 12% of lymphomas in dogs. TZL cells exhibit an activated phenotype, indicating the disease may be antigen-driven. Prior research found that asymptomatic aged Golden Retrievers (GLDRs) commonly have populations of T-zone-like cells (phenotypically identical to TZL) of undetermined significance (TZUS). OBJECTIVE: To evaluate associations of inflammatory conditions, TZL and TZUS, using a case-control study of GLDRs. ANIMALS: TZL cases (n = 140), flow cytometrically diagnosed, were identified through Colorado State University's Clinical Immunology Laboratory. Non-TZL dogs, recruited through either a database of owners interested in research participation or the submitting clinics of TZL cases, were subsequently flow cytometrically classified as TZUS (n = 221) or control (n = 147). METHODS: Health history, signalment, environmental, and lifestyle factors were obtained from owner-completed questionnaires. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated using multivariable logistic regression, obtaining separate estimates for TZL and TZUS (versus controls). RESULTS: Hypothyroidism (OR, 0.3; 95% CI, 0.1-0.7), omega-3 supplementation (OR, 0.3; 95% CI, 0.1-0.6), and mange (OR, 5.5; 95% CI, 1.4-21.1) were significantly associated with TZL. Gastrointestinal disease (OR, 2.4; 95% CI, 0.98-5.8) had nonsignificantly increased TZL odds. Two shared associations for TZL and TZUS were identified: bladder infection or calculi (TZL OR, 3.5; 95% CI, 0.96-12.7; TZUS OR, 5.1; 95% CI, 1.9-13.7) and eye disease (TZL OR, 2.3; 95% CI, 0.97-5.2; TZUS OR, 1.9; 95% CI, 0.99-3.8). CONCLUSIONS AND CLINICAL IMPORTANCE: These findings may elucidate pathways involved in TZUS risk and progression from TZUS to TZL. Further investigation into the protective association of omega-3 supplements is warranted.

Successful medical management of pseudomembranous cystitis in three cats with lower urinary tract obstruction.

CASE REPORT: The present case series describes the clinical course and outcome of three cats diagnosed with pseudomembranous cystitis. This is an uncommon presentation of lower urinary tract obstruction but can be easily be identified by ultrasonography, revealing severe bladder wall thickening and thin hyperechoic luminal strips. The condition can be secondary to severe bacterial urinary tract infection. All cats were successfully treated with medical management only, mainly based on antimicrobials and individualised supportive therapy. CONCLUSION: Further evaluation of this condition is necessary in order to determine potential underlying aetiologies, pathophysiological mechanisms and the most appropriate standardised treatment.

Use of Purina Pro Plan Veterinary Diet UR Urinary St/Ox to Dissolve Struvite Cystoliths.

The objective of this study was to determine the efficacy of feeding the commercially available diet, Purina Pro Plan Veterinary Diets UR Urinary St/Ox, for the dissolution of struvite cystoliths in cats with naturally occurring disease. Twelve cats with clinical signs of lower urinary tract disease and cystoliths confirmed via radiographs were enrolled. The cats were fed the study diet ad libitum and assessed by abdominal radiographs weekly. Cats with cystoliths that resolved based on radiographs and confirmatory ultrasound examination were considered diet successes. Cats with no change in cystolith size after 2-6 weeks underwent cystotomy for stone removal, aerobic culture and antimicrobial susceptibility testing, and analysis. All cats accepted the study diet, and weight loss was not noted over the course of the study. Total cystolith dissolution was achieved by week 2 for 5 cats, which were presumed to have struvite cystoliths. All other cats underwent cystotomy for stone removal after radiographic evidence of cystoliths were still present at 2 weeks (1 cat with severe signs), 4 weeks (5 cats), or 6 weeks (1 cat). The cystoliths that were surgically removed were calcium oxalate (5 cats) and mixed (2 cats) and would not be expected to dissolve with this diet. Follow-up radiographs from 6 cats fed the diet long term (3 presumed struvite and 3 with other cystoliths removed surgically) were collected from 1 to 6 months after beginning the study and showed no evidence of cystolith recurrence. While larger case numbers are needed, these results suggest that feeding Purina Pro Plan Veterinary Diets UR Urinary St/Ox can successfully dissolve cystoliths that are likely struvite and may lessen the risk of recurrence of struvite and calcium oxalate cystoliths.

Use of a laparoscopic specimen retrieval pouch to facilitate removal of intact or fragmented cystic calculi from standing sedated horses: 8 cases (2012-2015).

OBJECTIVE To evaluate the use of a laparoscopic specimen retrieval pouch for removal of intact or fragmented cystic calculi from standing horses. DESIGN Retrospective case series. ANIMALS 8 horses (5 geldings and 3 mares) with cystic calculi. PROCEDURES Physical examination and cystoscopic, ultrasonographic, and hematologic evaluations of urinary tract function were performed for each horse. A diagnosis of cystic calculus was made on the basis of results of cystoscopy and ultrasonography. Concurrent urolithiasis or other urinary tract abnormalities identified during preoperative evaluation were recorded. Horses were sedated and placed in standing stocks, and the perineum was aseptically prepared. Direct access to the urinary bladder was gained in geldings via perineal urethrotomy or in mares by a transurethral approach. Calculi were visualized endoscopically, manipulated into the retrieval pouch, and removed intact or fragmented (for larger calculi). RESULTS For 4 geldings and 1 mare, fragmentation was necessary to facilitate calculus removal. Mean duration of surgery was 125 minutes, and trauma to the urinary bladder and urethra was limited to areas of hyperemia and submucosal petechiation. No postoperative complications were encountered for any horse. When lithotripsy was required, the retrieval pouch provided an effective means of stabilizing calculi and containing the fragments for removal. CONCLUSIONS AND CLINICAL RELEVANCE Use of the laparoscopic specimen retrieval pouch was an effective, minimally traumatic method for retrieving cystic calculi from standing horses. The pouch protected the urinary bladder and urethra from trauma during calculus removal and allowed for stabilization, containment, and fragmentation of calculi when necessary.

Evaluation of 21 426 feline bladder urolith submissions to the Canadian Veterinary Urolith Centre (1998-2014).

This study reports emerging trends in feline urolithiasis in Canada during the past 16.8 y, evaluates associations of breed and gender with urolith types, and reports on feline submissions from outside of Canada. Struvite and calcium oxalate uroliths comprised > 90% of all uroliths submitted. In cats, oxalate submissions outnumbered struvite submissions from Canada, Hong Kong, Denmark, and the United Arab Emirates, while Australian struvite submissions outnumbered calcium oxalate submissions. In Canada, the majority of urolith submissions were from domestic cats followed by Himalayan, Persian, and Siamese cats. Males were more likely to form calcium oxalate uroliths and females were more likely to develop struvite uroliths. Compared to domestic short-haired cats, Tonkinese, Burmese, Devon rex, Himalayan, Persian, and Siamese cats were significantly associated with calcium oxalate urolith submission. Egyptian mau, Birman, ocicat, and Siamese breeds were over-represented amongst urate submissions.

Évaluation de 21 426 soumissions d'urolithes de vessie au Centre canadien d'urolithes vétérinaires (1998­2014). Cette étude présente un rapport sur les tendances émergentes pour l'urolithiase féline au Canada pendant les 16,8 dernières années, évalue les associations avec la race et le sexe pour les types d'urolithes et établit un rapport sur les soumissions félines provenant de l'extérieur du Canada. Les urolithes de struvite et d'oxalate de calcium représentaient > 90 % de tous les urolithes soumis. Chez les chats, les soumissions d'oxalate étaient supérieures aux soumissions de struvite pour les échantillons provenant du Canada, de Hong Kong, du Danemark et des Émirats arabes unis, tandis que les soumissions de struvite provenant de l'Australie étaient supérieures aux soumissions d'oxalate de calcium. Au Canada, la majorité des soumissions d'urolithes provenaient de chats domestiques suivis des chats himalayens, persans et siamois. Il était plus probable que les mâles aient des urolithes d'oxalate de calcium et il était plus probable que les femelles développent des urolithes de struvite. Comparativement aux chats domestiques à poil court, les chats tonkinois, burmese, Devon rex, himalayens, persans et siamois présentaient une association importante avec une soumission d'urolithes d'oxalate de calcium. Les races de chat Mau égyptien, birman, ocicat et siamois étaient surreprésentées parmi les soumissions d'urate.(Traduit par Isabelle Vallières).

Transurethral Cystoscopy and Endoscopic Urolith Removal in Female Guinea Pigs (Cavia porcellus).

Urinary diseases are commonly found in guinea pigs. Diagnostic workup includes clinical examination, blood testing, imaging studies, urine culture, and urinalysis. This article describes the use of transurethral cystoscopy in female guinea pigs as an ancillary tool to diagnose abnormalities within the bladder and urethra. In addition, the transurethral cystoscopic removal of uroliths measuring up to 5 mm and situated within the urinary bladder is described.

Effects of two calculolytic diets on parameters of feline mineral metabolism.

OBJECTIVES: To evaluate the influence of two feline calculolytic diets on selected parameters of mineral metabolism. MATERIALS AND METHODS: Two dry commercial diets designed for struvite urolith dissolution were evaluated in 14 cats. The study was designed as a two-sequence, four-period crossover protocol with a baseline period, two 60-day "run-in" periods in which calculolytic diets (Diet 1 and Diet 2) were fed and one 30-day "wash-out" period. Data are expressed as median (range). RESULTS: Feeding the calculolytic diets for two months did not alter plasma concentrations of calcium, phosphorus, magnesium and parathyroid hormone. A significant (P < 0.05 in each case) decline in calcitriol was observed after administering both diets from 236.4 (122.4-429.6) to 170.4 (108.0-394.3) pmol/L (Diet 1) and from 278.4 (153.6-492.0) to 177.1 (87.6-392.4) pmol/L (Diet 2). Cats fed Diet 1 showed a significant increase in urine calcium concentration (from 0.3 (0.2-0.5) to 0.4 (0.3-0.7) mmol/L). Magnesium concentration in urine was significantly increased with both diets, from 1.4 (0.1-1.7) to 1.5 (1.3-2.4) mmol/L (Diet 1) and from 1.1 (0.4-1.9) to 2.0 (0.1-3.1) mmol/L (Diet 2). CLINICAL SIGNIFICANCE: Both diets resulted in an increased urinary concentration of magnesium, through different mechanisms: urine acidification (Diet 1) and increased sodium load (Diet 2).