Non-Renal Lesions of Uraemia in Domestic Cats.

Uraemia is a clinical syndrome caused by an increase in uraemia-associated toxins in the bloodstream as a consequence of intrinsic kidney or lower urinary tract diseases. Cats seem to be more affected by urinary tract diseases than dogs, particularly considering that chronic kidney disease (CKD) is one of the most important conditions in cats. Considering the lack of information on the systemic lesions of uraemia in cats, the aim of this study was to investigate the prevalence and clinical and pathological aspects of non-renal lesions in uraemic cats, with special attention to the differences between cats and dogs. Cats necropsied between 2000 and 2019 (n = 1,330) were investigated for urinary tract diseases and non-renal lesions of uraemia. The prevalence of uraemic cats with non-renal lesions (n = 78) was 5.8%. Adult, elderly and male animals were predominantly affected. Anorexia, apathy and vomiting were the most common clinical signs and CKD was observed in the majority of uraemic cats. Pulmonary oedema was the most frequent non-renal lesion identified. In contrast with previous reports, haemorrhagic and ulcerative gastritis was frequently observed, whereas soft tissue mineralization and parathyroid hyperplasia were uncommon features. Fibrous osteodystrophy was not observed. Cats with urinary tract diseases did not have as wide a variety of non-renal uraemic lesions as uraemic dogs and multisystemic manifestation of uraemia was observed in only 24.4% of cases.

Dystrophic mineralization in uremic dogs: an update / Mineralização distrófica em cães urêmicos: uma atualização

Pathological mineralization is the abnormal deposition of minerals in body tissues, previously injured or not. In these lesions, in addition to calcium, other minerals can be found at lower concentrations. Classically, mineralization is divided into two types: dystrophic and metastatic. However, currently, there is no consensus among researchers on the type of mineralization that occurs in uremic dogs. The objective of this study was to elucidate the type of pathological mineralization that occurs in dogs with uremic syndrome through the correlation of biochemical examinations with gross and histopathological changes, given the existence of controversial information on this theme in the specialized literature. The Shapiro-Wilk, D'Agostino and Pearson tests were used to evaluate data normality distribution, and analysis of variance (ANOVA) was applied to compare the data between more than two groups. Additionally, the Dunnett's multiple comparison test was used in the comparison between the Control Group (CG) and the Experimental Groups (G1, G2, and G3). Serum levels of urea, creatinine, total and ionized calcium, phosphorus, calcium-phosphorus product (CPP), parathyroid hormone (PTH), and albumin of 40 azotemic dogs with chronic kidney disease (CKD) were evaluated. Dogs were categorized by degree of azotemia (mild, moderate, and severe). Ionized hypocalcemia was observed in 97.5% (39/40) of the dogs, and no animals presented ionized hypercalcemia. Hyperphosphatemia was frequent (62.5%), especially in dogs with severe azotemia. PTH concentration increased with progression of azotemia, and high PTH levels were verified in 100% of the dogs with severe azotemia. CPP >60mg2/dl2 was observed in 75% (30/40) of the dogs. Of the 29 dogs that died during the study period, 16 were necropsied. Soft tissue mineralization was observed in 93.7% (15/16) of these dogs at gross and histopathological evaluation (HE and Von Kossa), regardless of the degree of azotemia, in nine organs/tissues: kidneys (75%), lungs (50%), stomach (31.2%), heart (25%), larynx (25%), intercostal muscles (25%), aorta (6.2%), intestines (6.2%), and tongue (6.2%). In one animal, the serosa of all segments of the small intestine showed whitish, rough, irregular, multifocal plaques of varying sizes, confirmed by histopathology as dystrophic mineralization of the longitudinal outer muscular layer, which presented necrosis of coagulation and of the intestinal serosa. This intestinal lesion has not been described in dogs with uremic syndrome to date. In conclusion, the laboratory and histopathologic data previously described, especially regarding tissue and vascular mineralization, which occur in association with previous degenerative/necrotic lesions in the absence of hypercalcemia in dogs with CKD, assist with clarifying inconsistencies found in the existing literature. Therefore, conceptually, mineralization that occurs in uremic dogs should be considered dystrophic.(AU)

Mineralização patológica é a deposição anormal de minerais em tecidos previamente lesados ou não. Nessas lesões, além do cálcio, outros minerais podem ser encontrados em concentrações inferiores. Classicamente, as mineralizações são divididas em dois tipos: distrófica e metastática. Contudo, atualmente, ainda não há consenso entre os pesquisadores sobre o tipo de mineralização que ocorre em cães urêmicos. Objetivou-se com esse estudo elucidar o tipo de mineralização patológica que ocorre em cães com síndrome urêmica através da correlação de exames bioquímicos com alterações macroscópicas e histopatológicas, visto a existência de informações controversas na literatura especializada. Os dados obtidos foram submetidos ao teste de Shapiro-Wilk e teste de D'Agostino e Pearson para avaliação da normalidade da distribuição e para comparação de dados em mais de dois grupos foi utilizado o teste ANOVA. Adicionalmente, o teste de comparações múltiplas de Dunnett permitiu a comparação entre o grupo controle (GC) com os demais grupos (G1, G2 e G3). Foram avaliados os níveis séricos de ureia, creatinina, cálcio total e ionizado, fósforo, produto cálcio-fósforo (PCF), PTH e albumina de 40 cães azotêmicos com doença renal crônica (DRC). Os cães foram classificados quanto ao grau de azotemia (leve, moderada e severa). Verificou-se hipocalcemia ionizada em 97,5% (39/40) dos cães e, em nenhum animal houve hipercalcemia ionizada. Hiperfosfatemia foi frequente (62,5%), principalmente em cães com azotemia severa. A concentração do PTH aumentou conforme a progressão da azotemia, encontrando-se elevada em 100% dos cães com azotemia severa. Em 75% (30/40) dos cães o PCF foi superior a 60mg2/dl2. Durante o estudo, 29 cães morreram, sendo 16 desses necropsiados. Em 93,7% (15/16) desses cães observou-se mineralização de tecidos moles, durante a avaliação macroscópica e histopatológica (HE e Von Kossa), independentemente do grau de azotemia, em nove órgãos/tecidos: rins (75%), pulmões (50%), estômago (31,2%), coração (25%), laringe (25%), músculos intercostais (25%), aorta (6,2%), intestino (6,2%) e língua (6,2%). Adicionalmente, em um animal verificou-se na serosa de todos os segmentos do intestino delgado placas multifocais brancacentas, rugosas, irregulares de tamanhos variados, cuja histopatologia confirmou tratar-se de mineralização distrófica da camada longitudinal muscular externa que apresentava necrose de coagulação e da serosa intestinal. Essa lesão intestinal nunca havia sido descrita em cães com síndrome urêmica. Em suma, os dados laboratoriais e histopatológicos aqui descritos, sobretudo, no que se refere à mineralização tecidual e vascular, que ocorrem relacionadas a lesões degenerativo-necróticas prévias, na ausência de hipercalcemia, em cães com DRC, ajudam a esclarecer as incongruências existentes na literatura. Por conseguinte, conceitualmente, as mineralizações que ocorrem em cães urêmicos devem ser consideradas distróficas.(AU)

Associations between dialysate sodium concentration and plasma sodium concentration of dogs receiving intermittent hemodialysis treatments.

OBJECTIVE To compare dialysate sodium concentration and patient plasma sodium concentration of dogs during intermittent hemodialysis treatments. SAMPLE 211 intermittent hemodialysis treatments performed on 40 client-owned dogs for the management of dialysis-dependent uremia. PROCEDURES Medical records were reviewed to determine the plasma sodium concentration of each dog before and after routine hemodialysis treatments. Associations between detected changes in plasma sodium concentration and dialysate sodium concentration were evaluated by use of Spearman rank correlations and linear regression analysis. RESULTS Significant linear correlations were found between the dialysate sodium concentration and patient sodium concentration. The starting dialysate-to-patient sodium gradient was associated with the strongest correlation to the change in patient sodium concentration at the end of the dialysis session. Modest correlations existed between the dialysate sodium concentration and postdialysis patient sodium concentration as well as between the predialysis dialysate-to-patient sodium gradient and postdialysis dialysate-to-patient sodium gradient. CONCLUSIONS AND CLINICAL RELEVANCE The dialysate sodium concentration was correlated with the patient sodium concentration in dogs, and the dialysate-to-patient sodium gradient could be used to further refine this association to predict the postdialysis patient sodium concentration and potentially manage dysnatremia during hemodialysis. Prospective studies should be performed to determine how these associations can be used to correct aberrations as well as to avoid unwanted alterations in patient sodium concentrations.

The uremic toxin methylguanidine increases the oxidative metabolism and accelerates the apoptosis of canine neutrophils.

We investigated the hypothesis that the increased concentration of plasma methylguanidine (MG) increases oxidative metabolism and accelerates apoptosis of neutrophils from dogs with chronic kidney disease (CKD). To achieve this, the levels of MG were quantified in healthy (n=16) and uremic dogs with CKD stage 4 of according to the guidelines of the International Renal Interest Society (IRIS, 2015) (n=16) using high performance liquid chromatography (HPLC). To evaluate the isolated effect of MG on neutrophil oxidative metabolism and apoptosis, neutrophils isolated from 12 healthy dogs were incubated with the highest concentration of plasma MG (0.005g/L) observed in dogs with CKD. Neutrophil oxidative metabolism was assessed by flow cytometry, using the probes hydroethidine for superoxide production and 2',7'-dichlorofluorescein diacetate for hydrogen peroxide production, with or without phorbol myristate acetate (PMA) stimulus. Neutrophil apoptosis and viability were also evaluated in flow cytometer using the Annexin V-PE system, with or without the apoptosis-inducing effect of camptothecin. Uremic dogs presented higher concentrations of MG (p<0.0001), increased oxidative stress and primed neutrophils with higher apoptosis rate. The neutrophil abnormalities observed in vivo were also reproduced in vitro, using cells isolated from healthy dogs and incubated with MG. We obtained strong evidence that in dogs with CKD, increased MG levels contributed to oxidative stress and potentially compromised the non-specific immune response by altering the oxidative metabolism and viability of canine neutrophils.

Hypothermia in Uremic Dogs and Cats.

BACKGROUND: The prevalence of uremic hypothermia (UH) and the effects of improving uremia on body temperature have not been determined in veterinary patients. OBJECTIVES: To determine the prevalence of UH and correlations between uremia and body temperature in patients undergoing intermittent hemodialysis (IHD). ANIMALS: Uremic dogs (n = 122) and cats (n = 79) treated by IHD at the Bobst Hospital of the Animal Medical Center from 1997 to 2013. METHODS: Retrospective review of medical records. RESULTS: The prevalence of hypothermia was 38% in azotemic cats and 20.5% in azotemic dogs. Statistically significant temperature differences were observed between uremic and nonuremic dogs (nonuremic: mean, 100.8°F; range, 91.2-109.5°F; uremic: mean, 99.9°F; range, 95.6-103.8°F; P < .0001) and cats (nonuremic: mean, 100.6°F; range, 94.0-103.8°F; uremic: mean, 99.3°F; range, 92.3-103.4°F; P < .0001). In dog dialysis patients, significant models included (1) timing (pre-dialysis versus post-dialysis) with weight class (small [P < .0001], medium [P = .016], and large breed [P = .033] dogs), (2) timing with serum creatinine concentration (P = .021), and (3) timing with BUN concentration (P < .0001). In cat dialysis patients, there was a significant interaction between timing and weight as a categorical variable (<5 kg and ≥5 kg). CONCLUSIONS AND CLINICAL IMPORTANCE: Uremic hypothermia appears to be a clinical phenomenon that occurs in cats and dogs. Uremic patients are hypothermic compared to ill nonuremic patients and body temperatures increase when uremia is corrected with IHD in dogs and in cats >5 kg. In cats, UH seems to be a more prevalent phenomenon driven by uremia. Uremic hypothermia does occur in dogs, but body weight is a more important predictor of body temperature.

Epidemiologia e distribuição de lesões extrarrenais de uremia em 161 cães / Epidemiology and distribution of extrarenal lesions of uremia in 161 dogs

Com o objetivo de determinar a epidemiologia e as características morfológicas, incluindo a localização anatômica, das lesões extrarrenais de uremia, bem como determinar as principais lesões do sistema urinário associadas à ocorrência de uremia, foram revisados os protocolos de necropsias de cães realizadas no Laboratório de Patologia Veterinária da Universidade Federal de Santa Maria de janeiro de 1996 a dezembro de 2012 (17 anos). Nesse período foram necropsiados 4.201 cães, sendo que 161 (3,8%) apresentaram lesões extrarrenais de uremia. Em 134 cães (83,2%) foram descritos sinais clínicos associados à uremia. As lesões extrarrenais mais frequentes, em ordem decrescente, foram: gastrite ulcerativa e hemorrágica (56,5%), mineralização de tecidos moles (55,9%), edema pulmonar (47,2%), estomatite e/ou glossite ulcerativa (30,4%), endocardite/trombose atrial e aórtica (28,6%), hiperplasia das paratireoides (9,3%), osteodistrofia fibrosa (8,1%), anemia (6,2%), laringite ulcerativa (5%), enterite ulcerativa/hemorrágica (3,7%), esofagite fibrinonecrótica (1,9%) e pericardite fibrinosa (1.9%). Na maioria dos casos as lesões extrarrenais de uremia foram decorrentes de azotemia prolongada por lesões renais graves, sendo as mais prevalentes a nefrite intersticial e a glomerulonefrite.

The aim of this study was to determine the epidemiology and the morphological characteristics (including the anatomic localization) of the extrarenal uremic lesions, as well as to describe the main lesions of the urinary system associated with the occurrence of uremia, through analysis of the protocols of necropsies performed in dogs from January 1996 to December 2012 (17 years) at the Laboratório de Patologia Veterinária of the Universidade Federal de Santa Maria. A total of 4,201 dogs were necropsied and 161 (3.8%) had extrarenal uremic lesions. In 134 dogs (83.2%) clinical signs associated with uremia were reported. The extrarenal lesions more often observed, in descending order of prevalence, were ulcerative and hemorrhagic gastritis (56.5%), soft-tissue mineralization (55.9%), pulmonary edema (47.2%), ulcerative stomatitis and/or glossitis (30.4%), endocarditis/atrial and aortic thrombosis (28.6%), parathyroid hyperplasia (9.3%), fibrous osteodystrophy (8.1%), anemia (6.2%), ulcerative laryngitis (5%), ulcerative and hemorrhagic enteritis (3.7%), fibrinonecrotic esophagitis (1.9%), and fibrinous pericarditis (1.9%). In most of the cases, the extrarenal lesions of uremia were due to prolonged azotemia secondary to severe renal lesions, such as interstitial nephritis and glomerulonephritis (the most prevalent ones).

Doença renal policística em bezerro / Polycystic kidney disease in a calf

Este relato descreve um caso de doença renal policística em um bovino, macho, mestiço, com um ano de idade. Ao exame clínicoobservou-se estado nutricional ruim, mucosas pálidas, desidratação moderada (8% a 10%), úlceras na região ventral da língua,áreas multifocais de hipotricose recobertas por crostas por todo o corpo e decúbito esterno-lateral permanente. Na avaliação dohemograma observou-se principalmente anemia arregenerativa e leucocitose devido à neutrofilia com desvio à [confirmar] esquerda.Na necropsia, os rins estavam aumentados de volume, pálidos e com a superfície natural finamente irregular. Histologicamente, haviasubstituição quase completa da cortical renal por múltiplos e pequenos cistos, distensão dos espaços de Bowman, regeneraçãotubular, fibrose, edema e leve infiltrado inflamatório linfoplasmocítico intersticial.

This report describes a case of polycystic kidney disease in a male, mixed breed bovine aged one year. On clinical examinationrevealed a poor nutritional status, pallid mucous membranes, moderated dehydration (8 to 10%), ulcers on the ventral portion ofthe tongue, multifocal areas of hypotrichosis covered with scabs throughout the entire body and permanent sternolateral decubitus.The blood exam revealed aregenerative anemia and leukocytosis (neutrophilia) with deviation to the left. The necropsy revealedenlarged, pallid kidneys with a finely irregular natural surface. The histological analysis revealed the nearly complete replacementof the renal cortex by numerous small cysts, distension of the Bowman space, tubular regeneration, fibrosis, edema and mildinterstitial lymphoplasmacytic inflammatory infiltrate.

Relationship among serum creatinine, serum gastrin, calcium-phosphorus product, and uremic gastropathy in cats with chronic kidney disease.

BACKGROUND: Chronic kidney disease (CKD) in cats is associated with gastrointestinal signs commonly attributed to uremic gastropathy. Consequently, patients often are treated with antacids and gastrointestinal protectants. This therapeutic regimen is based on documented gastric lesions in uremic humans and dogs, but the nature and incidence of uremic gastropathy in cats are unknown. HYPOTHESIS/OBJECTIVES: Evaluate uremic gastropathy in CKD cats to facilitate refinement of medical management for gastrointestinal signs. ANIMALS: Thirty-seven CKD cats; 12 nonazotemic cats METHODS: Stomachs were evaluated for the presence of classic uremic gastropathy lesions. Histopathologic lesions were compared with serum creatinine concentrations, calcium-phosphorus product (CPP), and serum gastrin concentrations. RESULTS: Gastric ulceration, edema, and vascular fibrinoid change were not observed. The most important gastric lesions in CKD cats were fibrosis and mineralization. Sixteen CKD cats (43%) had evidence of gastric fibrosis of varying severity and 14 CKD cats (38%) had gastric mineralization. CKD cats were more likely to have gastric fibrosis and mineralization than nonazotemic controls (P = .005 and P = .021, respectively). Only cats with moderate and severe azotemia had gastric mineralization. CPP was correlated with disease severity; severely azotemic CKD cats had significantly higher CPP when compared with nonazotemic controls, and to mildly and moderately azotemic cats (P < .05). Gastrin concentrations were significantly higher in CKD cats when compared with nonazotemic controls (P = .003), but increased concentrations were not associated with gastric ulceration. CONCLUSIONS AND CLINICAL IMPORTANCE: Uremic gastropathy in CKD cats differs from that described in other species and this difference should be considered when devising medical management.

Leishmaniasis causes oxidative stress and alteration of oxidative metabolism and viability of neutrophils in dogs.

The aim of the present study was to test the hypothesis that oxidative stress and alteration of oxidative metabolism and apoptosis of neutrophils in dogs vary with the stage of leishmaniasis and to determine the contribution of uremia to such alterations. Dogs with leishmaniasis were classified into two stages: moderate (Leish II, n=20) or very severe (i.e. with concurrent uremia; Leish IV, n=20) according to the LeishVet Consensus. The two leishmaniasis groups were compared with uremic dogs without leishmaniasis (Uremic, n=10) and to healthy dogs (Control, n=30). To determine oxidative stress, total antioxidant/oxidant capacity, lipid peroxidation, total glutathione and the plasma antioxidants albumin, uric acid and bilirubin were quantified. Superoxide production was determined using the hydroethidine probe and viability and apoptosis were measured using annexin V-PE by capillary flow cytometry. Oxidative stress was present in both uremia and leishmaniasis with reduced total antioxidant capacity and was associated with increased induced production of superoxide and apoptosis. The greatest amount of oxidants was observed in animals with moderate disease only. Neutrophils from uremic dogs with and without leishmaniasis had decreased viability and an increased apoptosis rate in addition to increased lipid peroxidation. In conclusion, oxidative stress occurs in both stages of leishmaniasis with differences in intensity and levels of plasma markers; however, uremia does contribute to the decreased spontaneous viability of neutrophils in dogs in the final stage of the disease.

Estresse oxidativo e aumento da apoptose em neutrófilos de cães com azotemia pré-renal / Oxidative stress and increase in apoptosis index of neutrophils from dogs with prerenal azotemia

O presente trabalho tem como objetivo testar a hipótese de que, à semelhança do que ocorre na uremia, cães com azotemia pré-renal sofrem estresse oxidativo, o qual está relacionado com alterações do metabolismo oxidativo e apoptose dos neutrófilos. Para tal, foi determinada a peroxidação lipídica pela quantificação do malondialdeído (MDA) e o status antioxidante total do plasma de 15 cães normais e 10 com azotemia pré-renal, correlacionando-os com a produção de superóxido e o índice apoptótico dos neutrófilos. As determinações do MDA e do status antioxidante total foram estabelecidas empregando-se um conjunto de reagentes comerciais. Por meio de citometria de fluxo capilar, a produção de superóxido e a apoptose de neutrófilos isolados de sangue periférico foram determinadas utilizando-se a sonda hidroetidina e o sistema anexina V-PE, respectivamente. Cães azotêmicos (26,29±5,32g/L) apresentaram menor concentração (p=0,0264) do antioxidante albumina em relação ao grupo-controle (30,36±3,29g/L) e também uma menor (p=0,0027) capacidade antioxidante total (2,36±0,32 versus 2,73±0,24mmol/L), enquanto não houve alteração da peroxidação lipídica plasmática e da produção de superóxido neutrofílica. Concluiu-se que, à semelhança do que ocorre na uremia, condições azotêmicas pré-renais no cão causam estresse oxidativo e aceleração da apoptose dos neutrófilos.

This study aims to test the hypothesis that, similarly to what occurs in uremia, dogs with prerenal azotemia suffer oxidative stress associated with changes in oxidative metabolism and apoptosis in neutrophils. For this purpose, fifteen normal dogs and ten with prerenal azotemia had lipid peroxidation determined by quantifying the malondialdehyde (MDA) and had plasma total antioxidant status evaluated, correlating them with the superoxide production and apoptotic index of neutrophils. MDA and plasma total antioxidant status were determined using commercial reagents. Using capillary flow cytometry, superoxide production and apoptosis were determined from isolated neutrophils of peripheral blood using the hydrithidine and Annexin V-PE probe system, respectively. Azotemic dogs (26.29±5.32g/L) had a lower concentration (p=0.0264) of the plasma antioxidant albumin than the control group (30.36±3.29g/L) and also had lower (p=0.0027) total antioxidant status (2.36±0.32 versus 2.73±0.24mmol/L), while no alterations were observed in plasma lipid peroxidation and superoxide production. It was concluded that, similarly to what occurs in uremia, prerenal azotemia causes oxidative stress and acceleration of neutrophil apoptosis in dogs.

Effect of dietary supplements in reducing probability of death for uremic crises in dogs affected by chronic kidney disease (masked RCCT).

Chitosan and alkalinizing agents can decrease morbidity and mortality in humans with chronic kidney disease (CKD). Whether this holds true in dog is not known. Objective of the study was to determine whether a commercial dietary supplement containing chitosan, phosphate binders, and alkalinizing agents (Renal), compared to placebo, reduces mortality rate due to uremic crises in dogs with spontaneous CKD, fed a renal diet (RD). A masked RCCT was performed including 31 azotemic dogs with spontaneous CKD. Dogs enrolled in the study were randomly allocated to receive RD plus placebo (group A; 15 dogs) or RD plus Renal (group B; 16 dogs). During a first 4-week period, all dogs were fed an RD and then randomized and clinically evaluated up to 44 weeks. The effects of dietary supplements on mortality rate due to uremic crises were assessed. At 44 weeks, compared to group A, dogs in group B had approximately 50% lower mortality rate due to uremic crises (P = 0.015). Dietary supplementation with chitosan, phosphate binders, and alkalinizing agents, along with an RD, is beneficial in reducing mortality rate in dogs with spontaneous CKD.

The kidney in critically ill small animals.

Critically ill animals may have preexisting renal disease or develop acute kidney injury as a consequence of their presenting complaint. Age, concurrent medical therapy, electrolyte and fluid imbalances, and exposure to potential nephrotoxicants are factors that predispose to acute kidney injury. Many risk factors are correctable or manageable, and these should be addressed whenever possible. Measurement of serum creatinine is insensitive for the detection of acute kidney injury, and clinicians should consider assessment of other parameters such as urine output, urinalysis, and urine chemistry results. A stepwise approach for management of acute kidney injury in small animal patients is outlined.

Urea kinetics and intermittent dialysis prescription in small animals.

Hemodialysis improves survival for animals with acute kidney injury beyond what would be expected with conventional management of the same animals. Clinical evidence and experience in human patients suggest a role for earlier intervention with renal replacement to avoid the morbidity of uremia and to promote better metabolic stability and recovery. For a large population of animal patients, it is the advanced standard for the management of acute and chronic uremia, life-threatening poisoning, and fluid overload for which there is no alternative therapy.

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.

Investigation of a syndrome characterised by passage of red urine in smallholder dairy cattle in East Usambara Mountains, Tanzania.

A case-control study was carried out to investigate a syndrome in smallholder dairy cattle in East Usambara Mountains characterised by urination of clotted blood. Smallholder dairy farms with the problem (cases) were matched with nearest farms without the problem (controls). In total, 30 farmers from Mbomole (19), Shebomeza (9) and Mlesa (2) villages in Amani division participated in the study. Using a structured questionnaire, information on risk factors associated with conditions characterised by passage of red urine in cattle was collected. In addition, serum samples from 80 smallholder dairy animals were collected and submitted for serodiagnosis of leptospirosis and babesiosis by microscopic agglutination test (MAT) and an indirect enzyme-linked immunosorbent assay (ELISA), respectively. Laboratory analysis showed that the seroprevalence of leptospirosis and babesiosis was 21.3% and 46.3%, respectively and there was no significant difference between'case' and 'control' farms (P > 0.05), hence the occurrence of urination of clotted blood syndrome in Amani was not explained. However, bracken fern (Pteridium aquilinum) was found to be ubiquitous in the area, and also found to be widespread in all areas used as sources of animal fodder Given the presence and distribution of bracken ferns and clinical signs and post-mortem lesions described by informants, chronic bracken-fern poisoning is more likely to be associated with the syndrome affecting animals in the study area. However, further investigation is required to confirm this observation so that appropriate control strategies can be devised.

Clinical, hematological, and biochemical findings in an outbreak of abortion and neonatal mortality associated with Trypanosoma evansi infection in dromedary camels.

This article presents the clinical and laboratorial findings in an outbreak of abortions and high neonatal mortality attributable to Trypanosoma evansi infection in camels. A total of 16 females were diagnosed, 2 of which showed moderate signs of chronic form, particularly hyporexia and intolerance to exercise. The main laboratorial findings were regenerative anemia (hemolytic anemia), lymphocytic and monocytic leukocytosis, hyperproteinemia, hyperglobulinemia, hypoglycemia, serum urea increased, and serum iron decreased. The most characteristic finding in the examined females would be the uremia, probably due to the higher protein metabolism.

Clinical evaluation of dietary modification for treatment of spontaneous chronic kidney disease in cats.

Objective-To determine whether a renal diet modified in protein, phosphorus, sodium, and lipid content was superior to an adult maintenance diet in minimizing uremic episodes and mortality rate in cats with stage 2 or 3 chronic kidney disease (CKD). Design-Double-masked, randomized, controlled clinical trial. Animals-45 client-owned cats with spontaneous stage 2 or 3 CKD. Procedures-Cats were randomly assigned to an adult maintenance diet (n = 23 cats) or a renal diet (22) and evaluated trimonthly for up to 24 months. Efficacy of the renal diet, compared with the maintenance diet, in minimizing uremia, renal-related deaths, and all causes of death was evaluated. Results-Serum urea nitrogen concentrations were significantly lower and blood bicarbonate concentrations were significantly higher in the renal diet group at baseline and during the 12- and 24-month intervals. Significant differences were not detected in body weight; Hct; urine protein-to-creatinine ratio; and serum creatinine, potassium, calcium, and parathyroid hormone concentrations. A significantly greater percentage of cats fed the maintenance diet had uremic episodes (26%), compared with cats fed the renal diet (0%). A significant reduction in renal-related deaths but not all causes of death was detected in cats fed the renal diet. Conclusions and Clinical Relevance-The renal diet evaluated in this study was superior to an adult maintenance diet in minimizing uremic episodes and renalrelated deaths in cats with spontaneous stage 2 or 3 CKD.

Risk factors associated with renal insufficiency in horses with primary gastrointestinal disease: 26 cases (2000-2003).

OBJECTIVE: To identify factors associated with renal insufficiency in colic- or colitis-affected horses with high serum creatinine (SCr) concentrations evaluated at a referral hospital. DESIGN: Retrospective case series. ANIMALS: 167 colic- or colitis-affected horses (88 represented a random sample [hospital population], and 79 had high SCr concentration at initial evaluation [study population]). PROCEDURE: Medical records were reviewed. Data collected included signalment; physical examination, clinicopathologic, and diagnostic findings; and outcome. The study population was categorized on the basis of whether SCr concentration did (AR group; n = 53) or did not (PA group; 26) normalize within 72 hours of fluid therapy. Characteristics of the study and hospital populations were compared. RESULTS: Males and Quarter Horses were significantly overrepresented in the study population. Compared with the hospital population, study-population horses were significantly more likely to have colitis, gastric reflux, and diarrhea at initial evaluation. Initial mean SCr concentration in the PA group was significantly higher than the AR group; identification of gastric reflux, abnormal rectal examination findings, and hypochloremia were significantly associated with persistent azotemia after 72 hours of fluid therapy. Compared with the AR group, PA group horses were 3 times as likely to die or be euthanized. CONCLUSIONS AND CLINICAL RELEVANCE: In colic- or colitis-affected horses, factors associated with renal insufficiency included gastric reflux, abnormal rectal examination findings, or hypochloremia initially; prognosis for horses in which azotemia resolves within 72 hours of treatment appears to be better than for horses with persistent azotemia.