Use of haemodiafiltration in the treatment of massive caffeine intoxication in a dog.

The objective of this case report is to describe the use of extracorporeal therapy, specifically hemodialfiltration, for the treatment of caffeine intoxication. A 12 year old Border Terrier consumed up to 1440 mg/kg of caffeine and rapidly developed clinical signs of tachycardia and tremors. Hemodiafiltration was instituted, using an M60 PrismaFlex cartridge using blood to prime the system due to patient size. Treatment with 11.25 L of therapy fluid (83% dialysate, 17% replacement fluid), or 1.8 L/kg, was provided over 6 h. Pre-treatment serum caffeine concentration of 233 µg/mL was decreased by 89% to 25 µg/nL by the end of treatment. Despite prompt institution of extracorporeal toxin removal therapy, ventricular ectopy developed necessitating sotolol treatment for the following week. Caffeine is efficiently removed via hemodialysis, as predicted by small size, small volume of distribution, and minimal protein binding. A CRRT platform can be used to provide adequate clearance.

Evaluation of Iatrogenic Hypocortisolemia Following Trilostane Therapy in 48 Dogs with Pituitary-Dependent Hyperadrenocorticism.

This study aimed to retrospectively describe the clinical progression following diagnosis of iatrogenic hypocortisolemia (iHC) in 48 dogs receiving trilostane for pituitary-dependent hyperadrenocorticism. Cortisol concentrations were ≥1.5 mg/dL within 6 mo following diagnosis of iHC in 76.3% of dogs (95% confidence interval [CI] 59.8-88.6%). At the time of study completion, 25% of dogs (95% CI 13.6-39.6%) were receiving either glucocorticoids or mineralocorticoids or both; 42% of dogs (95% CI 27.6-56.8%) were on no adrenal-related medications; and the remaining 33% of dogs (95% CI 20.4-48.4%) were receiving trilostane. No patient-, clinicopathologic-, or trilostane-associated factors were identified to influence adrenal recovery following diagnosis of iHC, and it remains difficult to predict the clinical progression in this population of dogs.

Effects of IV Fluids in Dogs and Cats With Kidney Failure.

Intravenous fluid therapy has long been the mainstay of treatment of kidney disease, including acute kidney injury and uremic crisis associated with chronic kidney disease. Careful management of fluid dose is critical, as animals with kidney disease may have marked derangements in their ability to regulate fluid homeostasis and acid-base status. Understanding of the physiology of renal fluid handling is necessary, along with repeated attention to parameters of fluid status, electrolytes, and acid-base balance, to achieve optimal hydration status and avoid further damage or decrease in function from dehydration or overhydration.

Hemodialysis catheter-associated fibrin sheath in a dog.

OBJECTIVE: To describe an intravascular fibrin sheath associated with a hemodialysis catheter in a dog. CASE SUMMARY: A 4-year-old dog presented for hemodialysis to treat acute kidney injury. Hemodialysis catheter dysfunction during the course of treatment was temporarily alleviated using a tissue plasminogen activator. A thrombus composed of fibrin and granulation tissue creating a sheath around the catheter and focally adherent to the vessel wall was identified on postmortem evaluation. NEW OR UNIQUE INFORMATION PROVIDED: Fibrin sheath formation is a commonly recognized problem of central venous catheters used for hemodialysis in people and is likely a common problem in veterinary patients undergoing dialysis as well. This report provides a description of the clinical features of the catheter dysfunction, response to treatment, postmortem radiographic and direct imaging, and histology of the fibrin sheath, and also provides a brief review of potential management techniques that have been described in people.

Managing Fluid and Electrolyte Disorders in Kidney Disease.

Because of the role of the kidneys in maintaining homeostasis in the body, kidney disease leads to derangements of fluid, electrolyte, and acid-base balance. The most effective therapy of a uremic crisis is careful management of fluid balance, which involves thoughtful assessment of hydration, a fluid treatment plan personalized for the specific patient, and repeated and frequent reassessment of fluid and electrolyte balance. Disorders of sodium, chloride, potassium, calcium, and phosphorus are commonly encountered in kidney disease and some may be life-threatening. Treatment of metabolic acidosis and nutritional support is frequently needed.

Is Progressive Chronic Kidney Disease a Slow Acute Kidney Injury?

International Renal Interest Society chronic kidney disease Stage 1 and acute kidney injury Grade I categorizations of kidney disease are often confused or ignored because patients are nonazotemic and generally asymptomatic. Recent evidence suggests these seemingly disparate conditions may be mechanistically linked and interrelated. Active kidney injury biomarkers have the potential to establish a new understanding for traditional views of chronic kidney disease, including its early identification and possible mediators of its progression, which, if validated, would establish a new and sophisticated paradigm for the understanding and approach to the diagnostic evaluation, and treatment of urinary disease in dogs and cats.

Evaluation of the relationship between clinical variables and thromboelastographic findings in dogs with protein-losing nephropathy.

OBJECTIVE: To determine whether hypercoagulability in proteinuric dogs, defined by thromboelastography (TEG), is related to the degree of proteinuria, presence of systemic arterial hypertension, presence of hypoalbuminemia, or reduced antithrombin activity. DESIGN: Prospective study of client-owned dogs. Data collected from each patient included signalment, body weight, urine protein-to-creatinine ratio (UPC), serum albumin concentration, TEG values, noninvasive arterial blood pressure, and AT activity. Hypercoagulability was diagnosed by TEG and odds ratios for other measurements were assessed by univariate logistic regression. SETTING: Urban referral center and teaching hospital. ANIMALS: Seventy-six dogs with protein-losing nephropathy (PLN) based on UPC, diagnosed between Oct 2009 and Oct 2012. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The prevalence of hypercoagulability was 89%. No statistically significant associations were detected between hypercoagulability and UPC, serum albumin, noninvasive blood pressure, or AT activity (all P > 0.05). The prevalence of thromboembolism was 6.6%. CONCLUSIONS: Hypercoagulability was prevalent in dogs with PLN but could not be predicted based upon the presence or degree of proteinuria, systemic arterial hypertension, hypoalbuminemia, or low AT activity. The prevalance of thromboembolism was low in this population with PLN.

IMAGING DIAGNOSIS--URINARY BLADDER DUPLICATION IN A CAT.

A female kitten presented for chronic, intermittent, antibiotic-responsive urinary incontinence and chronic kidney disease. Abdominal ultrasound identified bilateral pelvic/ureteral dilation and three closely apposed thin-walled fluid-filled structures in the caudal abdomen, extending toward the pelvic inlet. Excretory urography and negative contrast cystography identified contrast medium accumulation from the dilated ureters into two tubular soft tissue masses of the caudal abdomen, with subsequent gradual filling of a more cranially located urinary bladder. A retrograde vaginocystourethrogram identified a normal uterus, normal vagina, and a single urethra continuous with the cranially located urinary bladder. Antemortem diagnosis was suspicious for bilateral ectopic ureteroceles. Postmortem diagnosis, 35 months following initial presentation, determined the fluid-filled masses to have abundant smooth muscle in the wall, including a muscularis mucosa connected by a common ostium, consistent with urinary bladder duplication. Urinary bladder duplication should be included as a differential diagnosis in cats with these clinical and imaging characteristics. In this case, differentiation of ectopic ureterocele from urinary bladder duplication required histological confirmation.

Endoscopic-guided laser ablation of vestibulovaginal septal remnants in dogs: 36 cases (2007-2011).

OBJECTIVE: To describe the technique and evaluate short- and long-term outcomes in female dogs after endoscopic-guided laser ablation (ELA) of various vestibulovaginal septal remnants (VVSRs). DESIGN: Retrospective case series. ANIMALS: 36 dogs. PROCEDURES: Medical records of dogs with VVSRs that underwent ELA were retrospectively reviewed. All patients underwent complete cystourethrovaginoscopy for diagnosis and treatment. Endoscopic-guided laser ablation (with a holmium:yttrium-aluminum-garnet or diode laser) was used to transect the vaginal membrane. Patients with intramural ectopic ureters were concurrently treated with ELA of their ectopic ureters. Endoscopy was repeated 6 to 8 weeks after ELA of vaginal remnants in some patients, and the procedure sites were reassessed. RESULTS: 36 female dogs with persistent paramesonephric septal remnants (n = 19), vaginal septa (11), or dual vaginas (6) were included. Twenty-six dogs had urinary incontinence, 2 had recurrent UTIs, and 8 had both. Thirty of 36 (83%) dogs had concurrent ectopic ureters. Endoscopic-guided laser ablation was performed with holmium:yttrium-aluminum-garnet and diode lasers in 8 and 28 dogs, respectively. Five dogs had mild postoperative dysuria for < 24 hours. One patient developed a complication involving inadvertent laser perforation of the vaginal wall. There were no negative effects from this event, and the perforation was fully healed within 8 weeks. At the time of follow-up, all defects were fully healed with no sign of recurrence in the 18 (50%) patients reevaluated. There was a significant improvement in continence scores and a significantly decreased incidence of UTIs after ELA. The median follow-up time was 34 months (range, 8 to 57 months). CONCLUSIONS AND CLINICAL RELEVENCE: The results of the present study indicated that ELA provided an effective, safe, and minimally invasive treatment option for various VVSRs in dogs, avoiding the need for more invasive surgery.

Predictors of outcome for cats with ureteral obstructions after interventional management using ureteral stents or a subcutaneous ureteral bypass device.

Novel treatment alternatives for feline ureteral obstruction(s) include placement of a double pigtail ureteral stent and a subcutaneous ureteral bypass (SUB) device. This study evaluated parameters for the prediction of hospitalization times, peri-operative survival, renal recovery and long-term survival in cats with benign ureteral obstructions after successful decompression with either a ureteral stent or SUB device. The medical records of 41 cats treated for benign ureteral obstruction(s) were retrospectively reviewed. Preoperative historical, biochemical and imaging parameters, along with intra- and postoperative biochemical parameters and complications were evaluated for predictors of hospitalization length, survival to discharge, 3-, 6- and 9-month post-procedure creatinine, and overall survival time. All patients had successful decompression of their renal pelvis. Hospitalization time was positively associated with presenting creatinine, perioperative complications, post-procedure creatinine and potassium, but was negatively associated with post-procedure sodium. No parameters were associated with survival to discharge. A higher creatinine at discharge was positively associated with a higher creatinine at follow-up. A decreased overall survival was associated with a higher presenting blood urea nitrogen, higher creatinine at hospital discharge and in over-hydrated patients during hospitalization. Cats with International Renal Interest Society stage 1 and 2 kidney disease, versus stage 3 and 4, at 3 months and 6 months post-procedure, lived longer. Cats with ureteral obstruction(s) treated with a ureteral stent or SUB device had an overall good survival and no admitting parameter was associated with survival to discharge. No single parameter was associated with all outcomes in this study, making predicting patient survival and cost prior to ureteral decompression difficult.

Canine struvite urolithiasis.

Struvite calculi, composed of magnesium ammonium phosphate, have existed for thousands of years in human medicine and are a leading cause of calculi in companion animals. Struvite stones have also been called urease, infection-induced, phosphatic, and triple phosphate stones. They are the most common uroliths in dogs, in which most cases of struvite urolithiasis are associated with infection. Management of struvite urolithiasis requires a multimodal approach that addresses the presence of the urolith(s) and associated infection while identifying risk factors that predispose to the development of infection.

Proteinuria in dogs and cats.

Proteinuria is defined as the presence of protein in the urine. Normally, circulating serum proteins are blocked by the glomerulus due to size and/or charge. Any small proteins that pass through a healthy glomerulus are reabsorbed by the renal tubules or broken down by renal tubular epithelial cells. Persistent proteinuria, in the absence of lower urinary tract disease or reproductive tract disease, is usually an indication of renal damage or dysfunction. Less commonly persistent proteinuria can be caused by increased circulating levels of low molecular weight proteins. This article reviews mechanisms of proteinuria in dogs and cats and discusses the importance of screening for and ultimately treating proteinuria.

Long-term outcome of cats and dogs with acute kidney injury treated with intermittent hemodialysis: 135 cases (1997-2010).

OBJECTIVE: To determine the long-term outcome for small animal patients with acute kidney injury (AKI) treated with intermittent hemodialysis (IHD). DESIGN: Retrospective case series. ANIMALS: 42 cats and 93 dogs treated with IHD for AKI. PROCEDURES: Medical records of cats and dogs treated with IHD for AKI from January 1997 to October 2010 were reviewed. Standard methods of survival analysis with Kaplan-Meier product limit curves were used. The log-rank, Mann-Whitney, and Kruskal-Wallis tests were used to determine whether outcome, number of IHD treatments, or duration of hospitalization was different when dogs and cats were classified according to specific variables. RESULTS: The overall survival rate at the time of hospital discharge was 50% (21/42) for cats and 53% (49/93) for dogs. The overall survival rate 30 days after hospital discharge was 48% (20/42) for cats and 42% (39/93) for dogs. The overall survival rate 365 days after hospital discharge was 38% (16/42) for cats and 33% (31/93) for dogs. For all-cause mortality, the median survival time was 7 days (95% confidence interval, 0 to 835 days) for cats and 9 days (95% confidence interval, 0 to 55 days) for dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Cats and dogs with AKI treated with IHD have survival rates similar to those of human patients. Although there was a high mortality rate prior to hospital discharge, those patients that survived to discharge had a high probability of long-term survival.

Anemia of renal disease: what it is, what to do and what's new.

PATIENT GROUP: It is estimated that 15-30% of geriatric cats will develop chronic kidney disease (CKD), and that 30-65% of these cats will develop anemia as their renal disease worsens. Anemia of renal disease is multifactorial in its pathogenesis, but the main cause is reduced production of erythropoietin, a renal hormone that controls the bone marrow's production of red blood cells, as kidney disease progresses. PRACTICAL RELEVANCE: It is important to recognize the presence of anemia of renal disease so that adequate treatment may be instituted to improve quality of life and metabolic function. Erythrocyte-stimulating agents (ESAs), such as epoetin alfa, epoetin beta and darbepoetin alfa, have been developed to counteract the effects of decreased erythropoietin production by the kidneys. These treatments, which are the focus of this review, have 83% similarity in amino acid sequence to the feline hormone. On average, the target packed cell volume (>25%) is reached within 3-4 weeks of ESA therapy. CLINICAL CHALLENGES: The use of ESAs has been associated with a number of complications, such as iron deficiency, hypertension, arthralgia, fever, seizures, polycythemia and pure red cell aplasia (PRCA). Darbepoetin has a prolonged half-life compared with epoetin and thus can be given only once a week, instead of three times a week. The incidence of PRCA appears to be decreased with darbepoetin use when compared with epoetin use in cats. EVIDENCE BASE: There is limited published evidence to date to underpin the use of ESAs in cats. This review draws on the relevant publications that currently exist, and the authors' personal experience of using these therapies for over 5 years.

Treatment of accidental ethanol intoxication with hemodialysis in a dog.

OBJECTIVE: To describe the successful treatment of accidental ethanol intoxication with hemodialysis in a dog. CASE SUMMARY: A 1.5-year-old female intact mixed breed dog was presented in a comatose state believed to be due to ethanol intoxication. The initial 9 hours of supportive care treatment were complicated by multiple seizures and hypothermia, and resulted in only minimal improvement in the dog's level of consciousness. Hemodialysis was implemented and resulted in rapid clinical recovery, corresponding to a rapid decline in serum ethanol concentration. NEW OR UNIQUE INFORMATION PROVIDED: To the authors' knowledge, this is the first reported case of using hemodialysis to treat accidental ethanol intoxication in a dog. The patient's initial serum ethanol concentration was higher than those previously reported for cases of accidental ethanol intoxication in dogs, and the serum ethanol concentration was shown to rapidly decline during hemodialysis. Treatment with hemodialysis for severe ethanol intoxication was effective in this case and may be able to decrease morbidity and mortality in some cases.

The prevalence of microalbuminuria and proteinuria in cats with diabetes mellitus.

The prevalence of microalbuminuria (MA) and proteinuria was evaluated in 66 cats with diabetes mellitus (DM), 35 nondiabetic cats with other illness, and 11 healthy nondiabetic cats with use of the E.R.D.-HealthScreen Feline Urine Test. The MA prevalence was higher in the diabetic than in the nondiabetic sick and healthy control cats (70%, 39%, and 18% respectively, P < .0001). In addition, prevalence of proteinuria defined by a protein/creatinine ratio (UPC) > 0.4 was significantly higher in the diabetic cat than in the control cats (70%, 35%, and 9% respectively, P < .0001). There was a significant but weak correlation between the results of MA and UPC (P < .0001, r = 0.43). Our results showed that MA is common in cats with DM. Further studies are required to evaluate the prognostic value of the presence and the severity of MA in cats with DM.

Vascular access for extracorporeal renal replacement therapy in veterinary patients.

Vascular access is the first and most basic requirement for successful extracorporeal renal replacement therapy (ERRT). Dual-lumen catheters are the most commonly used method of vascular access for ERRT in veterinary patients. An adequately functioning dialysis catheter allows for smooth and efficient patient management, whereas a poorly functioning catheter frustrates the technician, doctor, and patient. These catheters are fairly quick to place but require meticulous care for optimal function. The most common complications are thrombosis and infection. Monitoring catheter performance should be a routine part of dialysis patient care.

Equipment commonly used in veterinary renal replacement therapy.

Hemodialysis is a highly technical procedure that requires specialized equipment that is not used in other areas of veterinary medicine. Certain hemodialysis-specific monitoring equipment is also employed.

Methods of urolith removal.

Multiple techniques exist to remove uroliths from each section of the urinary tract. Minimally invasive methods for removing lower urinary tract stones include voiding urohydropropulsion, retrograde urohydropropulsion followed by dissolution or removal, catheter retrieval, cystoscopic removal, and cystoscopy-assisted laser lithotripsy and surgery. Laparoscopic cystotomy is less invasive than surgical cystotomy. Extracorporeal shock wave lithotripsy can be used for nephroliths and ureteroliths. Nephrotomy, pyelotomy, or urethrotomy may be recommended in certain situations. This article discusses each technique and gives guidance for selecting the most appropriate technique for an individual patient.