A Carrel patch technique for renal transplantation in cats.

OBJECTIVE: To evaluate the feasibility of a Carrel patch method in feline renal transplantation. STUDY DESIGN: Descriptive case series. ANIMALS: Nine healthy donor cats and 9 client recipient cats with chronic renal failure. METHODS: Renal transplantation was performed in 9 cats with chronic renal failure after collection of a donor's left kidney with a Carrel patch technique. A patch of donor aortic wall was removed with either 2 or 1 renal artery (ies) (n = 1 and 8 cats, respectively) central to the patch, with a cuff of tissue (≤1 mm) protruding from the base of the vessels. The Carrel patch was implanted in recipient cats with an end-to-side artery-to-aorta anastomosis, in a simple-continuous pattern of 9-0 nylon. The renal vein and ureter were implanted as previously described. RESULTS: All donors and recipients survived surgery without vascular complication. CONCLUSION: The Carrel patch is a novel approach allowing the harvest of kidneys with multiple renal arteries. The technique also simplified the implant procedure, potentially decreasing the risks of bleeding and thrombosis.

Ureteral Papilla Implantation as a Technique for Neoureterocystostomy in Cats Undergoing Renal Transplantation: 30 Cases.

OBJECTIVE: To describe the clinical outcome of donor and recipient cats undergoing ureteral papilla harvest and implantation as a technique for neoureterocystostomy in clinical kidney transplant. STUDY DESIGN: Retrospective case series. ANIMALS: Donor (n=31) and recipient (n=30) cats that underwent kidney harvest and transplantation using ureteral papilla implantation technique for neoureterocystostomy. METHODS: Medical records for donor and recipient cats presented to the University of Wisconsin Veterinary Teaching Hospital from January 2003 to December 2014 were reviewed. Data recorded included complete blood count, serum chemistry panel, surgical technique, diagnostic imaging results, short- and long-term complications, and anesthetic survival. RESULTS: All 30 recipients recovered from anesthesia. Four died within 24 hours and 26 survived to hospital discharge. Serum creatinine was within the reference interval by 72 hours in 22/26 cats (85%). Complications related to the ureteral papilla implantation technique were seen in only 1 cat (3%). Uroabdomen diagnosed on day 3 ultimately resolved over the following 24 hours without surgical intervention. All 31 donor cats survived to discharge. Four donors (13%) experienced mild, transiently increased serum creatinine. CONCLUSION: Ureteral papilla implantation is a viable technique for neoureterocystostomy in cats undergoing kidney transplantation. Proposed benefits for the recipient include a less technically challenging anastomosis, decreased risk of ureteral obstruction at the anastomosis site, and reduced risk of leakage compared to previous reports. Benefits for recipients should be weighed against risks to donors, including a more complex ureteral harvest, increased surgical time, and potential injury or obstruction of the contralateral ureteral papilla.

Hyperammonaemia in four cats with renal azotaemia.

Hyperammonaemia is well reported in animals with advanced hepatic disease and portosystemic shunts, but is unreported in cats with renal disease. This case series describes four cats with severe renal azotaemia in which elevated ammonia levels were detected during the course of treatment. In two cases hyperammonaemia was detected at a time when neurological signs consistent with encephalopathy had developed. This raises the possibility that hyperammonaemia may play a role in the development of encephalopathy in cats with renal azotaemia.

Serum intact parathyroid hormone levels in cats with chronic kidney disease / Avaliação das concentrações séricas de paratormônio intacto em gatos com doença renal crônica

Chronic kidney disease (CKD) is frequently observed in cats and it is characterized as a multisystemic illness, caused by several underlying metabolic changes, and secondary renal hyperparathyroidism (SRHPT) is relatively common; usually it is associated with the progression of renal disease and poor prognosis. This study aimed at determining the frequency of SRHPT, and discussing possible mechanisms that could contribute to the development of SRHPT in cats at different stages of CKD through the evaluation of calcium and phosphorus metabolism, as well as acid-base status. Forty owned cats with CKD were included and divided into three groups, according to the stages of the disease, classified according to the International Renal Interest Society (IRIS) as Stage II (n=12), Stage III (n=22) and Stage IV (n=6). Control group was composed of 21 clinically healthy cats. Increased serum intact parathyroid hormone (iPTH) concentrations were observed in most CKD cats in all stages, and mainly in Stage IV, which hyperphosphatemia and ionized hypocalcemia were detected and associated to the cause for the development of SRHPT. In Stages II and III, however, ionized hypercalcemia was noticed suggesting that the development of SRHPT might be associated with other factors, and metabolic acidosis could be involved to the increase of serum ionized calcium. Therefore, causes for the development of SRHPT seem to be multifactorial and they must be further investigated, mainly in the early stages of CKD in cats, as hyperphosphatemia and ionized hypocalcemia could not be the only factors involved.

A doença renal crônica (DRC) em gatos é frequentemente observada e caracteriza-se como alteração multissistêmica, causada por alterações metabólicas, e o hiperparatireoidismo secundário renal (HPTSR) seria o mais comum e usualmente está associada com progressão da doença renal e mau prognóstico. Esse estudo teve como objetivo determinar a frequência do HPTSR, e discutir os possíveis mecanismos que podem contribuir para o desenvolvimento de SRHPT em gatos em diferentes estágios de DRC, pela avaliação do metabolismo do cálcio e fósforo, bem como do equilíbrio ácido-base. Quarenta gatos com DRC foram divididos em três subgrupos, de acordo com a classificação proposta pela International Renal Interest Society (IRIS), Estágio II (n=12), Estágio III (n=22) e Estágio IV (n=6). O grupo-controle foi composto por 21 gatos clinicamente saudáveis. O aumento das concentrações séricas de paratormônio intacto (PTHi) foi observado na maioria dos casos, mas principalmente no Estágio IV, no qual a hiperfosfatemia e a hipocalcemia ionizada parecem estar associadas ao desenvolvimento do HPTSR. No entanto, nos Estágios II e III, observou-se hipercalcemia ionizada, sugerindo que, nestes estágios, o desenvolvimento do HPTSR possa estar associado a outros fatores, e a acidose metabólica pode estar envolvida com o desenvolvimento de hipercalcemia ionizada. Assim, outros fatores, além da hiperfosfatemia e da hipocalcemia ionizada, possam estar envolvidos com o desenvolvimento do HPTSR, principalmente nos estágios iniciais da DRC. Futuros estudos são necessários para uma melhor compreensão da fisiopatologia do HPTSR em gatos.

Effect of weight loss in obese dogs on indicators of renal function or disease.

BACKGROUND: Obesity is a common medical disorder in dogs, and can predispose to a number of diseases. Human obesity is a risk factor for the development and progression of chronic kidney disease. OBJECTIVES: To investigate the possible association of weight loss on plasma and renal biomarkers of kidney health. ANIMALS: Thirty-seven obese dogs that lost weight were included in the study. METHODS: Prospective observational study. Three novel biomarkers of renal functional impairment, disease, or both (homocysteine, cystatin C, and clusterin), in addition to traditional markers of chronic renal failure (serum urea and creatinine, urine specific gravity [USG], urine protein-creatinine ratio [UPCR], and urine albumin corrected by creatinine [UAC]) before and after weight loss in dogs with naturally occurring obesity were investigated. RESULTS: Urea (P = .043) and USG (P = .012) were both greater after weight loss than before loss, whilst UPCR, UAC, and creatinine were less after weight loss (P = .032, P = .006, and P = .026, respectively). Homocysteine (P < .001), cystatin C (P < .001) and clusterin (P < .001) all decreased upon weight loss. Multiple linear regression analysis revealed associations between percentage weight loss (greater weight loss, more lean tissue loss; r = -0.67, r(2) = 0.45, P < .001) and before-loss plasma clusterin concentration (greater clusterin, more lean tissue loss; r = 0.48, r(2) = 0.23, P = .003). CONCLUSION AND CLINICAL IMPORTANCE: These results suggest possible subclinical alterations in renal function in canine obesity, which improve with weight loss. Further work is required to determine the nature of these alterations and, most notably, the reason for the association between before loss plasma clusterin and subsequent lean tissue loss during weight management.

Bilateral ureteropelvic junction stenosis causing hydronephrosis and renal failure in an adult cat.

A 3.5-year-old male neutered cat was presented for investigation of renomegaly appreciated during a routine physical examination. Marked renomegaly due to bilateral hydronephrosis was detected and further testing identified International Renal Interest Society stage 2, non-hypertensive, non-proteinuric chronic kidney disease. Ten months later the cat was evaluated for acute lethargy; severe azotemia with oliguria was documented. Medical therapy failed to result in clinical improvement and the cat was euthanased. Necropsy revealed bilateral marked hydronephrosis secondary to a tortuous proximal ureter consistent with proximal ureteropelvic junction stenosis. This is the first report of this disorder leading to progressive renal failure in a cat.

Dilated ureters, renal dysplasia, and chronic renal failure in an African elephant (Loxodonta africana).

An ultrasonographic reproductive health examination of a 26-yr-old female African elephant (Loxodonta africana) revealed bilateral ureteral wall thickening and dilatation. On ultrasonographic examination, the bladder and both ureters were normal near the trigone; however, the cranial-most aspect of each ureter was dilated and thickened for a length of 30-50 cm. The same month, elevated blood creatinine (3.0 mg/dl), and urine protein-creatinine ratio (4.0) were observed. Chronic renal failure was diagnosed based on these abnormalities, and the persistent ureteral dilatation was seen on subsequent ultrasound examinations. Complete blood cell counts, serum chemistries, and urinalyses remained relatively unchanged until 24 mo after diagnosis, at which time azotemia, hypophosphatemia, and hypercalcemia (including elevated ionized calcium) developed. Hydronephrosis of both kidneys and prominent sacculation of the left ureter were noted on ultrasonographic examination. Lethargy, ventral edema, and oral mucosal ulceration acutely developed 30 mo after diagnosis. Although blood urea nitrogen remained elevated, creatinine, total calcium, and ionized calcium returned to within reference ranges at that time. Due to rapid clinical decline and grave prognosis, humane euthanasia was elected. Bilateral ureteral dilatation, dysplasia of the right kidney, and chronic nephritis of the left kidney were identified postmortem.

Interaction of clarithromycin with cyclosporine in cats: pharmacokinetic study and case report.

Clarithromycin (CLM) has been known to increase the cyclosporine (CsA) trough levels in human transplant patients. However, the interaction of CLM with CsA has not been reported in cats. In this study, the effects of oral dosing of CLM on the pharmacokinetics and dosing of CsA in cats were investigated. Co-administration of CLM with CsA resulted in significant increases of oral bioavailability of CsA. In addition, CLM reduced the CsA dosage required to maintain the therapeutic CsA trough levels to almost 35% of the initial CsA therapy and the dose frequency was successfully replaced from a twice a day schedule to once a day in a feline kidney transplant patient. The addition of CLM to the regular CsA-based immunosuppression could be used as an effective alternative to classical ketoconazole treatment in feline kidney transplant patients and may result in substantial cost saving and convenience for the cat owners.

The use of darbepoetin to stimulate erythropoiesis in anemia of chronic kidney disease in cats: 25 cases.

BACKGROUND: Anemia is present in 30-65% in cats with chronic kidney disease (CKD) and few long-term treatment options exist. Darbepoetin is effective in treating anemia of kidney disease in humans and may be used in cats. HYPOTHESIS/OBJECTIVE: To evaluate the use of darbepoetin, a recombinant analog of human erythropoietin, to stimulate erythropoiesis, and to effectively treat anemia of kidney disease in cats. ANIMALS: Twenty-five of 66 cats that received ≥ 2 doses of darbepoetin at the Animal Medical Center between January 2005 and December 2009 were included in this study. METHODS: Cats were included in the study if they received darbepoetin and follow-up data were available for at least 56 days and had CKD as a primary clinical diagnosis. Cats were excluded if they were treated with darbepoetin but did not have kidney disease. Response to treatment was defined as reaching or exceeding a target packed red blood cell volume or hematocrit of 25%. RESULTS: Fourteen of 25 cats responded. Thirteen of those 14 cats received a dosage of 1 µg/kg/wk or higher. Presumptive adverse effects included vomiting, hypertension, seizures, and fever. CONCLUSIONS AND CLINICAL RELEVANCE: Darbepoetin is effective for treatment of anemia of kidney disease in cats. Pure red cell aplasia appears to be less common with darbepoetin than with epoetin usage.

Renal transitional-cell carcinoma in two cats with chronic kidney disease.

Two 12-year-old cats were diagnosed with chronic kidney disease (CKD) based on physical examination, clinicopathologic data and, in one case, abdominal ultrasound findings. Approximately 1 year after the initial diagnosis of CKD both cats developed renal transitional cell carcinoma (TCC)--bilateral in one cat. Based on post-mortem examination, one cat had no evidence of metastasis and the other had metastasis to the large intestine, heart and lungs. This is the first report of de novo bilateral renal TCC in a cat, as well as the first report of renal TCC developing in cats with previous history of confirmed CKD.

Use of end-to-side arterial and venous anastomosis techniques for renal transplantation in two dogs.

CASE DESCRIPTION: A sexually intact male Old English Sheepdog and a sexually intact female Bull Terrier were evaluated for renal dysplasia and chronic renal failure, respectively. CLINICAL FINDINGS: Both dogs were anemic and had high serum concentrations of urea nitrogen and creatinine. Electrolyte abnormalities (calcium and phosphorus) were also evident. The decision was made to pursue renal transplantation, and donor dogs were identified. TREATMENT AND OUTCOME: End-to-side anastomosis of the renal artery and vein of each donor's left kidney to the recipient's ipsilateral external iliac artery and vein, respectively, was performed. The left caudal abdominal musculature was scarified by making an incision, and nephropexy to that musculature was performed with a simple interrupted pattern of polypropylene sutures. No intraoperative or postoperative complications associated with the vascular anastomoses were encountered. Azotemia, anemia, and electrolyte imbalances resolved after transplantation. CLINICAL RELEVANCE: The end-to-side anastomosis technique described here, which is a preferred method in human medicine, was successful, providing an alternative to other renal transplantation techniques in dogs. Additional studies are needed to determine whether any vascular anastomosis technique is preferable for use in dogs requiring renal transplantation.

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.

Azodyl, a synbiotic, fails to alter azotemia in cats with chronic kidney disease when sprinkled onto food.

The effect of probiotic therapy in chronic kidney disease (CKD) in cats is poorly defined, but gaining in popularity. However, cat owners often prefer to administer probiotics by combining them with food, rather than administering capsules intact, as is prescribed by the manufacturer. The efficacy of such non-recommended administration is unknown. In this double-blinded, controlled clinical trial, 10 cats with naturally-occurring CKD were randomized to receive either a probiotic-prebiotic combination (synbiotic) or psyllium husk (prebiotic only) for 2 months. Medications were sprinkled and mixed into food or given as a slurry. Blood urea nitrogen (BUN) and creatinine were measured twice prior to administration of medication, and then monthly for 2 months during the medication administration. Owners and clinicians were masked as to treatment. The maximal percentage change in BUN and creatinine was calculated for each cat. No differences in percentage change were detected between groups (P=0.8 for both BUN and creatinine). The synbiotic supplement used in this study, when applied to food or administered as a slurry fails to reduce azotemia in cats with CKD. Therefore, owners should not administer this synbiotic in this manner.

Metastatic calcinosis (including calcinosis cutis) in a young dog with multiple urinary tract abnormalities.

Metastatic calcinosis associated with chronic renal failure and multiple urinary tract abnormalities was diagnosed in a 6-month-old Brittany spaniel that was presented with calcinosis cutis. This case report highlights the importance of skin as an indicator of systemic disease. The aetiopathogenesis of the four main types of tissue calcification is defined and discussed with an emphasis on metastatic calcinosis.

Evaluation of intrarenal mesenchymal stem cell injection for treatment of chronic kidney disease in cats: a pilot study.

The feasibility of autologous intrarenal mesenchymal stem cell (MSC) therapy in cats with chronic kidney disease (CKD) was investigated. Six cats (two healthy, four with CKD) received a single unilateral intrarenal injection of autologous bone marrow-derived or adipose tissue-derived MSC (bmMSC or aMSC) via ultrasound guidance. Minimum database and glomerular filtration rate (GFR) via nuclear scintigraphy were determined pre-injection, at 7 days and at 30 days post-injection. Intrarenal injection did not induce immediate or long-term adverse effects. Two cats with CKD that received aMSC experienced modest improvement in GFR and a mild decrease in serum creatinine concentration. Despite the possible benefits of intrarenal MSC injections for CKD cats, the number of sedations and interventions required to implement this approach would likely preclude widespread clinical application. We concluded that MSC could be transferred safely by ultrasound-guided intrarenal injection in cats, but that alternative sources and routes of MSC therapy should be investigated.

Renal dysplasia in Beagle dogs: four cases.

Anomalies of renal development comprise abnormalities in the amount of renal tissue (agenesis and hypoplasia); anomalies of renal position, form, and orientation; and renal dysplasia. There are previous reports of canine renal dysplasia in different breeds but none in the Beagle breed. This is the first report of renal dysplasia in this breed of dog. Morphologic descriptions of the range of microscopic features observed in four cases of renal dysplasia from preclinical studies in laboratory Beagle dogs are presented (including persistent primitive mesenchyme, persistence of metanephric ducts, asynchronous differentiation of nephrons, and atypical tubular epithelium), along with a basis for the classification of the lesion.

Cause and clinical characteristics of rib fractures in cats: 33 cases (2000-2009).

OBJECTIVE: To characterize the clinical features and population differences among cats sustaining traumatic and nontraumatic rib fractures. DESIGN: Retrospective clinical study. SETTING: University small animal hospital. ANIMALS: Thirty-three cats with radiographic evidence of rib fractures. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Cats with rib fractures were identified by performing a computer search of the radiology database. Thirty-three cats that sustained rib fractures were identified between January 2000 and September 2009. Seventeen cats had fractures due to trauma and 16 were deemed to occur from nontraumatic causes. A Mann-Whitney rank-sum test revealed statistically significant differences in the median ages between the 2 groups. Older cats were more likely to sustain rib fractures as a result of a presumed nontraumatic causes. A Chi-square analysis showed that nontraumatic fractures occurred significantly more often in the midbody region and involved the 9th-13th ribs. The majority of cats with presumed nontraumatic rib fracture had respiratory disease; the remaining cats had chronic renal disease or neoplasia. Cats with traumatic rib fractures had external signs of trauma. CONCLUSION: Rib fractures in cats may be clearly associated with trauma, or may be an incidental finding in cats with comorbidities. Cats with diseases that cause prolonged respiratory effort or coughing, metabolic diseases, or certain neoplasms, are at increased risk of spontaneous nontraumatic rib fractures.

Potential risks, prognostic indicators, and diagnostic and treatment modalities affecting survival in dogs with presumptive aspiration pneumonia: 125 cases (2005-2008).

OBJECTIVE: To evaluate a clinical population of dogs diagnosed with presumptive aspiration pneumonia (AP) and determine diagnostic and treatment modalities contributing to survival. DESIGN: Retrospective study. SETTING: A university veterinary teaching hospital in an urban setting. ANIMALS: One hundred and twenty-five dogs with presumed AP treated from 2005 to 2008. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Dogs with presumptive AP identified by a review of medical records had an overall survival of 81.6% (102/125). Male large-breed dogs (mean 24.9 kg; 82/125) were overrepresented and were more likely to develop AP in this study population. Recent anesthesia had been performed in 16% (20/125), and vomiting was reported in 64% (80/125). The most common radiographic findings were a predominantly alveolar pattern (187/272, [68.8%] total lung lobes) in the right middle lung lobe (80/115, [69.6%]). A mean of 2 lung lobes were involved radiographically, and the relationship between survival and the number of lung lobes affected was statistically significant (P=0.04). Neutrophilia with a left shift was common with no significant change on consecutive daily evaluations. The mean PaO(2) was 77.7 mm Hg (SD, 17.5 mm Hg) (range, 40.7-100 mm Hg) with a median alveolar-arterial gradient of 41.1 mm Hg (range, 8.1-81.8 mm Hg). In this study population, 37.6% (47/125) of dogs had microbial cultures performed and of these, 76.6% (36/47) were positive for growth; Escherichia coli (38.8%), Mycoplasma spp. (21.3%), Pasturella spp. (19.1%), and Staphylococcus spp. (17%) were the most common isolates in either single or multiagent infections. No treatment modality was statistically associated with increased survival. Colloid therapy was a negative prognostic indicator. CONCLUSIONS: In this study the overall prognosis for AP was good. Patients with only 1 affected lung lobe appeared more likely to survive. Supportive treatment modalities are warranted for the hospitalized patient, although no individual treatment method was found to be clearly superior to others.

Hypophosphatemia in cats after renal transplantation.

OBJECTIVE: To report the prevalence of hypophosphatemia after renal transplantation in a historical cohort of cats. DESIGN: Case series. ANIMALS: Cats (n=86) that received a renal allograft. METHODS: Medical records (January 200-June 2006) were reviewed. Signalment, clinical signs, pre- and postoperative diet, pre- and postoperative clinicopathologic variables, renal histopathology, and outcome were retrieved. Prevalence, onset, duration, treatment and associated clinical signs of hypophosphatemia were recorded. A chi(2) test was used to compare hemolysis frequency between cats with normal serum phosphorus concentration or a single spurious low serum phosphorus concentration for <24 hours duration (group 1) and confirmed hypophosphatemia for >24 hours (group 2). A Cox proportional hazards model was used to evaluate the effects of hypophosphatemia on survival while controlling for other potentially confounding variables (age, sex, weight, body condition score, and pre- and 24 hours postoperative clinicopathologic variables). RESULTS: Eighty-six cats (mean age, 7.7 years) were identified. Hypophosphatemia occurred in 32 cats (37%), with a median onset of 2 days and median duration of 4 days. Treatment was initiated in 48 (56%) of hypophosphatemic cats. Survival and hemolysis frequency was not significantly different between groups, and no risk factors were identified. CONCLUSION: Hypophosphatemia occurs in cats after renal transplantation and does not affect survival. CLINICAL RELEVANCE: The clinical importance of hypophosphatemia in renal transplant recipients remains unknown.

Renal dysplasia and nephrosclerosis in calves.

Renal dysplasia and nephrosclerosis in six calves, which were aged three to six months and from different farms in western Scotland and north-west England, was characterised clinically by stunted growth and renal failure with uraemia. Affected animals were depressed and one case exhibited severe neurological signs. Reduced erythrocyte counts were evident in three of four animals from which blood samples were submitted for haematology. At postmortem examination, the kidneys were bilaterally small, pale and firm, with marked fibrosis and sometimes contraction of the capsule. Histologically, affected calves had disorganised atrophic glomeruli, dilatation of tubules, loss of nephrons, areas of undifferentiated mesenchyme and diffuse interstitial and periglomerular fibrosis. There was minimal inflammation. Renal dysplasia and nephrosclerosis is a form of juvenile nephropathy of unknown aetiology that occurs sporadically in calves in the UK.