Effective removal of gadolinium with hemodialysis in a dog with severe acute on chronic kidney injury.

OBJECTIVE: To describe the use of intermittent hemodialysis (IHD) to remove gadolinium (28.1 mg/kg dose) in a dog with severe kidney disease. CASE SUMMARY: A 12-year-old neutered female Yorkshire Terrier presented with severe acute-on-chronic kidney injury and concurrent neurological signs. The dog received extracorporeal therapy as part of management. Uremia improved after hemodialysis, but central nervous system signs persisted; therefore, a contrast-enhanced magnetic resonance imaging was performed, immediately followed by IHD. Two IHD treatments with a low-flux dialyzer were performed 1.5 and 25.75 hours after administration of gadolinium, with almost complete removal of gadolinium. More than 96% of gadolinium was removed with a single treatment. NEW OR UNIQUE INFORMATION PROVIDED: Extracorporeal therapy is effective at removing gadolinium-based chelated contrast agents and could be considered if magnetic resonance imaging is indicated in a patient with substantial kidney impairment. Alternatively, newer contrast agents that have been deemed safer in this patient population could be used.

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.

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.

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.

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.

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.

Hemodialysis in a dog with acute renal failure from currant toxicity.

A 3 1/2-year-old Labrador retriever being presented for acute onset vomiting and lethargy was diagnosed with acute renal failure (ARF). The dog had ingested dried currants, a type of raisin. Hemodialysis was successfully performed to treat the ARE Raisin toxicity can cause ARF and warrants early recognition and aggressive treatment.

Acute intrinsic renal failure in cats: 32 cases (1997-2004).

OBJECTIVE: To determine patient demographics, clinicopathologic findings, and outcome associated with naturally acquired acute intrinsic renal failure (ARF) in cats. DESIGN: Retrospective case series. ANIMALS: 32 cats with ARF. PROCEDURES: Cats were considered to have ARF if they had acute onset of clinical signs (< 7 days), serum creatinine concentration > 2.5 mg/dL (reference range, 0.8 to 2.3 mg/dL) and BUN > 35 mg/dL (reference range, 15 to 34 mg/dL) in conjunction with urine specific gravity < 1.025 or with anuria or increasing serum creatinine concentration despite fluid therapy and normal hydration status, and no signs of chronic renal disease. Cases were excluded if cats had renal calculi or renal neoplasia. RESULTS: Causes of ARF included nephrotoxins (n = 18 cats), ischemia (4), and other causes (10). Eighteen cats were oliguric. For each unit (mEq/L) increase in initial potassium concentration, there was a 57% decrease in chance of survival. Low serum albumin or bicarbonate concentration at initial diagnosis was a negative prognostic indicator for survival. Initial concentrations of BUN, serum creatinine, and other variables were not prognostic. Seventeen (53%) cats survived, of which 8 cats had resolution of azotemia and 9 cats were discharged from the hospital with persistent azotemia. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that survival rates of cats with ARF were similar to survival rates in dogs and that residual renal damage persisted in approximately half of cats surviving the initial hospitalization.

Hyperthyroidism and the kidney.

Hyperthyroidism and chronic renal failure (CRF) are both common diseases of older cats. Hyperthyroidism increases GFR by a variety of physiologic effects. Chronic renal failure can suppress total T4 concentrations in cats with concurrent hyperthyroidism, and free T4 is not a useful distinguishing test. Medical therapy (ie, methimazole) is recommended in cats with pre-existing CRF. Overt renal failure occurs in approximately 30% of cats treated for hyperthyroidism. It usually occurs within one month of treatment and tends to remain mild and stable over time. There is no practical way to predict which cats will develop CRF after treatment of hyperthyroidism, although GFR measurement does seem useful.

Urinalysis interpretation: how to squeeze out the maximum information from a small sample.

The urinalysis is an essential part of the diagnostic evaluation for all urinary and many metabolic diseases. Its assessment includes evaluation of physical characteristics (color, clarity, and volume), biochemical parameters (urine pH, blood, glucose, ketones, bilirubin, urobilinogen, and protein) and microscopic sediment evaluation (RBC, WBC, organisms, epithelial cells, crystals, and casts). Many of these parameters are influenced by collection method and therefore, it is essential to interpret accordingly. Knowledge of factors that can interfere with the accuracy of some test results can decrease improper interpretation. When all of these parameters are evaluated in combination with clinical signs, physical examination, thorough history and other laboratory tests, a diagnosis will often be attained.

The use of erythropoietin.

EPO is a hematopoietic growth factor produced in the kidney that stimulates erythropoiesis. It effectively treats hypoproliferative anemia associated with CRF, improving quality of life in these patients. Other uses that are poorly characterized in veterinary medicine include treatment of cancer patients on chemotherapy, hematologic disorders, and anemic FeLV-infected cats as well as preoperative conditioning for elective surgeries that may involve significant blood loss. Careful monitoring of therapy is necessary for optimal results. Several complications are associated with rHuEPO therapy. The production of anti-rHuEPO antibodies is the most significant and can be a life-threatening event. Alternatives to human EPO are being sought to provide beneficial effects while avoiding antibody formation.

Leptospirosis. A re-emerging zoonotic disease.

Leptospirosis is a re-emerging infectious disease that occurs in dogs in urban and rural environments. It is caused by a filamentous spiral bacterium that has a predilection for renal tubules. Acute renal failure, hepatic dysfunction, and hemorrhagic diathesis are the most common clinical signs. Treatment with antibiotics and supportive care can manage a high percentage of cases successfully. Newer vaccines developed in response to the change in frequency of certain serovars may decrease the incidence of clinical disease. Leptospirosis affects a wide variety of species and is zoonotic.

Cryptococcal pyelonephritis in a dog.

A 5-year-old castrated male Golden Retriever was evaluated for polyuria, polydipsia, and progressive regurgitation thought to be a result of bacterial pyelonephritis and megaesophagus. Bacteriologic culture of urine failed to yield clinically relevant growth, and results of a urine sediment examination were normal. With time, intention tremors and progressive neurologic dysfunction were also observed. At necropsy, a diagnosis of cryptococcal disease was confirmed histologically and immunohistochemically. Findings in the dog of this report were indicative of nephrogenic diabetes insipidus with polyuria and polydipsia caused by cryptococcal pyelonephritis. Neurologic manifestations of systemic cryptococcus infection included megaesophagus, esophageal hypomotility, and regurgitation attributed to localization of cryptococcal organisms in the brain stem in the region of the dorsal motor nucleus of the vagus nerve. To the authors' knowledge, this is the first report of polyuria secondary to cryptococcal pyelonephritis.

Acute renal failure caused by lily ingestion in six cats.

Acute renal failure was diagnosed in 6 cats that had ingested Easter lily or tiger lily plants. All 6 were treated medically; 2 underwent hemodialysis. Three cats survived the acute episode, and although they had chronic renal failure, they survived for more than 1.5 years. Two cats died despite aggressive medical management, including hemodialysis. One cat was euthanatized shortly after the diagnosis was made. Three of the cats were oliguric or anuric at the time of initial examination, and all 3 died. None of the 3 cats that survived had oliguria or anuria. Various members of the lily family (Liliaceae) can cause nephrotoxicosis in cats, but the toxic principle is not known. Although the prognosis for full recovery of cats with lily toxicosis is poor, long-term survival is possible with supportive care. The prognosis appears to be better for cats with nonoliguric renal failure.