Canine renal failure syndrome in three dogs

Three dead dogs were brought to the College of Veterinary Medicine, Kyungpook National University for study. Clinically, all the dogs showed emaciation, anorexia, depression, hemorrhagic vomiting and diarrhea for 7~10 days before death. All the clinical signs were first noted for about one month after feeding the dogs with commercial diets. At necropsy, all 3 dogs had severe renal damage with the same green-yellowish colored nephroliths in the renal pelvis. They also showed systemic hemorrhage and calcification of several organs, which might have been induced by uremia. Microscopically, necrosis, calcification and calculi were detected in the renal tubules, and especially in the proximal convoluted tubules and collecting ducts of the kidney. These findings were supportive of a mycotoxic effect, and especially on their kidneys. However, the precise cause of the toxic effect in these cases of canine renal failure could not be determined.     

Abnormal development of nephrons in claudin-16-defective Japanese black cattle

The kidneys of 37 Japanese Black calves aged 2 to 65 months diagnosed with Claudin 16 (CL-16) defect by the DNA-based test were examined pathologically. The animals exhibited clinical symptoms such as growth impairment, renal failure, overgrowth of hooves, and anemia at a young age. There was no correlation between the time of onset and age. Kidney weights relative to body weight were similar to those in normal animals, but both kidney net weights and size were reduced due to atrophy in animals that showed severe renal dysfunction. Histopathological examination of the kidneys showed reduction in the number of glomeruli, compensatory hypertrophy of glomeruli and tubules, and glomerular and tubular atrophy accompanied by interstitial fibrosis and lymphocytic infiltration. Glomeruli were clearly less in number in the kidneys of CL-16-defective animals than those of normal animals even in the cases with mild lesions. A small number of immature glomeruli and tubules were also detected, suggesting that there were fewer nephrons developed at birth in CL-16-defective animals. It was suggested that a defect of the CL-16 gene is involved in the "abnormal development of nephrons". Immunohistopathological examination of the kidneys showed that the epithelium of thick ascending limb of Henle was stained with anti-CL-16 antibody in the control animals, but not in the affected animals, suggesting a defect of CL-16 in the epithelium of renal tubules in the affected animals.     

Familial glomerulonephropathy in a litter of beagles

Membranoproliferative glomerulonephropathy was diagnosed in 5 of 7 adult Beagles from the same litter. Dogs were raised in more than 1 area of the United States. One died without evidence of renal disease when it was 3 years old. At 8 years of age, 2 dogs developed signs of uremia, including polyuria, polydipsia, and infrequent episodes of anorexia and vomiting. Serum biochemical variables and urine specific gravity values were consistent with renal azotemia. Both dogs had proteinuria. Although healthy, 3 of the 4 remaining Beagles had proteinuria. Of these 3, only 1 was azotemic. Membranoproliferative glomerulonephritis was diagnosed on the basis of results of histologic examination of renal biopsy specimens from 4 of the dogs. Electron microscopy performed on 3 of the renal biopsy specimens revealed identical lesions, consisting of an extremely thickened glomerular basement membrane with multilaminar splitting. Immunoglobulin or amyloid deposits were not detected. On the basis of similar clinicopathologic abnormalities, common genetic background, and identical histopathologic and electron microscopic findings, familial renal disease was diagnosed. Additional studies involving other related Beagles are needed to identify the hereditary nature of membranoproliferative glomerulonephropathy in Beagles.     

Veterinary hemodialysis: advances in management and technology.

Hemodialysis (HD) is a renal replacement therapy that can enable recovery of patients in acute kidney failure and prolong survival for patients with end-stage kidney failure. HD is also uniquely suited for management of refractory volume overload and removal of certain toxins from the bloodstream. Over the last decade, veterinary experience with HD has deepened and refined and its geographic availability has increased. As awareness of the usefulness and availability of dialytic therapy increases among veterinarians and pet owners and the number of veterinary dialysis facilities increases, dialytic management will become the standard of advanced care for animals with severe intractable uremia.     

Characterization of melamine-containing and calcium oxalate crystals in three dogs with suspected pet food-induced nephrotoxicosis

The histomorphologic characteristics and chemical composition of the crystals associated with suspected pet food-induced nephrotoxicosis in 3 dogs are described. Kidney specimens from 2 dogs, a 3-year-old Parson Russell Terrier and a 3-year-old Bernese Mountain Dog, were examined. Both developed acute renal failure after eating canned pet food on the 2007 Menu Foods recall list. The third case was a kidney specimen from a 1-year-old mixed-breed dog from a similar 2004 outbreak of canine renal failure in Taiwan, which occurred after eating a commercial dog food. Hematoxylin and eosin (HE), 72-hour Oil Red O (ORO72h), Alizarin Red S (pH 4.1-4.3), and Von Kossa stains; infrared (IR) spectroscopy; and scanning electron microscopy with energy dispersive X-ray analysis (SEM/EDXA) were performed to determine the histomorphologic characteristics and chemical composition of the crystals observed in each case. Histomorphologic findings in each case included acute, marked tubular degeneration and necrosis with many intratubular birefringent crystals, and lymphoplasmacytic interstitial nephritis. In each case, most of the crystals were rough, pale brown, and stained with ORO72h but did not stain with Alizarin Red S (pH 4.1-4.3) or Von Kossa stains; these features were consistent with a plastic or lipid. IR spectroscopy and SEM/EDXA results were consistent with melamine-containing crystals. A second crystal type identified in each case was smooth and platelike with staining characteristics and IR spectroscopy and SEM/EDXA results consistent with calcium oxalate crystals. Melamine-containing crystals have distinct light microscopic, histochemical, and SEM/EDXA characteristics that facilitate their identification in tissue.     

The clinical and morphologic features of nonepidermolytic ichthyosis in the golden retriever

A scaling disorder specific to Golden Retriever dogs has been recognized by both dermatologists and pathologists, but to date has not been well characterized. At the University of Pennsylvania's Laboratory of Toxicology and Pathology, 46 cases of ichthyosis were diagnosed histologically in Golden Retriever dogs from January 2004 to January 2007. A total of 22 dogs had skin lesions documented at younger than 1 year of age; 3 dogs between 1 and 2 years of age; 13 dogs developed lesions at older than 2 years; and the time of onset was unknown for 8 dogs. A total of 25 dogs were female, and 21 were male. All dogs had strikingly similar histopathologic changes that consisted of mild to moderate laminar orthokeratotic hyperkeratosis with an absence of epidermal hyperplasia and dermal inflammation. Ultrastructural analysis using a ruthenium tetroxide fixation method was performed on punch biopsy samples from 5 dogs and compared with 2 control dogs (1 clinically and histologically normal sibling of an affected dog and 1 Cairn Terrier). All affected dogs had retained and convoluted membranes with crystalline structures in the stratum corneum. Scattered keratinocytes in the granular cell layer had prominent, clear, membrane-bound, cytoplasmic vacuoles. Pedigree analysis of 14 dogs was compatible with autosomal recessive inheritance, but incomplete dominance could not be ruled out. This unique hyperkeratotic/scaling disorder in Golden Retrievers has distinctive clinical, histologic, and ultrastructural features, which are consistent with a primary cornification defect.     

Enterocystoplasty with Cystectomy and Subtotal Intracapsular Prostatectomy in the Male Dog

Urinary diversion by implantation of the ureters into an isolated segment of jejunum was evaluated in eight clinically normal male dogs. Total cystectomy and subtotal intracapsular prostatectomy were performed, and the intestinal loop was sutured to the prostatic remnant. General health, renal function, acid-base balance, urinary tract infection, and urinary continence were monitored during observation periods of 4 to 30 weeks. All dogs survived the observation period and seven were in excellent general health at the time of euthanasia. Six of the 16 ureterointestinal anastomoses were complicated by complete ureteral obstruction. Absorption of urea from the intestinal loop was speculated as the reason for significant increases in serum urea nitrogen concentrations in all of the dogs. Serum creatinine concentrations generally remained within the normal range, but were significantly increased from preoperative baseline values by week 30. There was dilation of 12 renal pelves and ureters in seven dogs. Urine bacterial cultures were positive in six dogs, but histologic evidence of pyelonephritis was present in only five kidneys. Ejaculation was not affected by the procedure, but epididymitis was present in five dogs. The dogs could urinate consciously and did not dribble urine continuously; however, they urinated hourly. While the procedure was well tolerated by the dogs, the frequency of urination makes this technique unacceptable for most household pets.     

Peritoneal dialysis in dogs and cats: 27 cases (1976-1987)

The records of 25 dogs and 2 cats treated with peritoneal dialysis during an 11-year period were evaluated. The indications for peritoneal dialysis were acute renal failure in 21 animals, chronic renal failure in 5 animals, and azotemia of undetermined cause in 1 animal. Peritoneal dialysis resulted in a significant (P less than 0.05) decrease in serum urea nitrogen concentration in 19 of the dogs and a significant (P less than 0.05) decrease in serum creatinine in 20 dogs. The most common complication of peritoneal dialysis was hypoalbuminemia (11 animals affected). Other common complications were dialysate retention/catheter obstruction (8 animals), peritonitis (6 animals), hypochloremia (6 animals), and subcutaneous leakage of dialysate (6 animals). Twelve dogs and 2 cats died during treatment, 6 dogs were euthanatized, and 1 dog was lost to follow-up evaluation. The remaining 6 dogs survived and were discharged from the hospital after successful peritoneal dialysis. On the basis of the results of this study, the authors concluded that peritoneal dialysis, although associated with a high complication rate, was a successful technique for reducing azotemia in dogs with acute and chronic renal failure. Survival rates were poor because of the severity of the underlying renal diseases.     

Clinicopathologic, histologic, and toxicologic findings in 70 cats inadvertently exposed to pet food contaminated with melamine and cyanuric acid

OBJECTIVE: To document clinicopathologic, histologic, and toxicologic findings in cats inadvertently exposed to pet food contaminated with melamine and cyanuric acid. DESIGN: Case series. ANIMALS: 70 cats from a single cattery inadvertently fed contaminated food that was the subject of a March 2007 recall. PROCEDURES: Clinical signs, clinicopathologic and histopathologic findings, and results of toxicologic analyses were recorded. RESULTS: Clinical signs were identified in 43 cats and included inappetence, vomiting, polyuria, polydipsia, and lethargy. Azotemia was documented in 38 of the 68 cats for which serum biochemical analyses were performed 7 to 11 days after consumption of the contaminated food. One cat died, and 13 were euthanized. Histologic examination of kidney specimens from 13 cats revealed intratubular crystalluria, tubular necrosis with regeneration, and subcapsular perivascular inflammation characterized by perivascular fibroplasia or fibrosis and inflammation with intravascular fibrin thrombi. Toxicologic analyses revealed melamine and cyanuric acid in samples of cat food, vomitus, urine, and kidneys. CONCLUSIONS AND CLINICAL RELEVANCE: In cats unintentionally fed pet food contaminated with melamine and cyanuric acid, the most consistent clinical and pathologic abnormalities were associated with the urinary tract, specifically tubular necrosis and crystalluria.     

Estimation of the proportions of dogs and cats that are surgically sterilized.

OBJECTIVE: To determine an estimate of the proportions of dogs and cats in Texas that are surgically sterilized and whether those proportions differed according to species and sex of the animal, level of responsibility of the owner, or geographic location. DESIGN: Cross-sectional study. ANIMALS: 43,831 dogs and cats > or = 6 months old. PROCEDURE: Information on sterilization rates was provided by 14 licensing agencies and 16 animal shelters in diverse regions of Texas. Univariate and multivariate analyses were used to compare sterilization rates among subpopulations of animals (dogs vs cats, males vs females, sheltered vs licensed, rural vs urban location). RESULTS: Overall, 12,893 (29.4%) of the animals (26.9% of dogs and 32.6% of cats) were sterilized. Proportions of animals sterilized were significantly different among subpopulations. CONCLUSIONS AND CLINICAL RELEVANCE: Although the cause of pet overpopulation is multifaceted, failure of owners to spay and castrate their animals is a major contributing factor. Significant differences in sterilization rates among subpopulations of dogs and cats suggest that organizations encouraging spaying and castration should use motivational techniques specific for the pet owners they are targeting.     

Ethylene glycol toxicosis in adult beef cattle fed contaminated feeds

Acute deaths of cows held in a drylot and fed several crop processing plant by-products were investigated. Clinical signs in affected cows included diarrhea, ataxia, recumbency, hypersalivation, and sunken eyes. A histological diagnosis of ethylene glycol toxicosis, based on numerous birefringent crystals in renal tubules, was supported by toxicologic findings.     

Chronic renal failure in young dogs–possible renal dysplasia

The clinico-pathological findings are described in thirteen young dogs with advanced renal disease. All but three dogs were less than 2 years old. Some had signs of renal dysfunction since birth. Presenting signs were variable but anorexia, lethargy and weight loss were most frequent. All dogs had raised blood urea levels and most passed dilute urine; proteinuria and anaemia were variable findings. At necropsy all dogs had extra-renal lesions of renal failure and finely granular or lobulated, shrunken kidneys. The microscopical appearances of the kidneys were not those of amyloidosis, inflammatory or glomerular disease but were considered likely to be of developmental origin. The renal lesions were divided into three histologically distinct groups.

• 1 Predominantly cystic and connective tissue changes, characterized by striking dilatation of glomerular capsular spaces and cortical tubules.
• 2 Atypical connective tissue changes in which there were segmental bands of fibrous tissue containing primitive glomerular and tubular structures.
• 3 Predominantly glomerular and connective tissue changes, characterized by varying degrees of glomerulosclerosis and widespread calcification of glomeruli, tubules and blood vessels.

All groups had cortical and medullary interstitial fibrosis but minimal inflammatory cell infiltrates.     

Aspergillus spp. panophthalmitis with intralenticular invasion in dogs: report of two cases

This case series describes the ocular, clinical and histologic manifestations of disseminated Aspergillosis in two dogs. Two dogs presented for severe unilateral panophthalmitis and secondary glaucoma with positive Aspergillus spp. titers. Case 1 showed no clinicopathologic systemic symptoms of fungal dissemination, however, case 2 was affected with acute renal failure. The affected eye of case 1 did not respond to medical therapy and was enucleated for comfort. The affected eye of case 2 responded to aggressive topical and systemic medical therapies, however, the patient was euthanized for acute renal failure. Globes were collected for histologic evaluation at the time of death. Histology of both revealed panophthalmitis with presence of significant intraocular hemorrhage, multifocal fungal granulomas, retinal and optic nerve changes consistent with secondary glaucoma, rupture of the anterior lens capsule, and fungal invasion and colonization of the intralenticular space. These cases represent a unique and devastating ocular manifestation of disseminated Aspergillosis. Cases presenting with uveitis and secondary glaucoma of unknown origin, especially with confirmed or suspected lens capsular rupture, should have serologic testing for this infectious agent.     

Cutaneous Wound Healing in Ehlers-Danlos Syndrome

Wound healing in five dogs and five cats affected with a connective tissue dysplasia resembling Ehlers-Danlos syndrome of humans was compared with wound healing in 10 nonaffected animals. Six skin incisions on the lateral aspects of the thorax and abdomen of each animal were sutured and assessed daily for 75 days for evidence of healing. All wounds in nonaffected dogs, affected cats, and nonaffected cats healed by first intention. Three incisions in affected dogs had dehiscence of all or part of the incision line and healed by granulation, contraction, and epithelialization. Biopsies taken at 3, 6, 9, 12, 15, and 75 days were compared histologically to determine if there were any differences in rates of healing between affected and nonaffected animals. Epidermal thickening and scab formation were noted at days 3 and 6 in both affected and nonaffected animals. Infiltration with mononuclear cells and fibroplasia steadily increased from day 6 to day 15 in all groups. Collagen fibril formation was evident by day 9. At day 75, incision sites were recognized by fine, more compact collagen bundles and lack of adnexal structures, as compared with the adjacent dermis in both affected and nonaffected animals. Although delayed wound healing has been reported to be a complication of Ehlers-Danlos syndrome in humans, using clinical and histologic criteria, wound healing in dogs and cats with Ehlers-Danlos syndrome appears to be similar to nonaffected animals.     

Clinical evaluation of dietary modification for treatment of spontaneous chronic renal failure in dogs

OBJECTIVE: To determine whether a diet used for dogs with renal failure (renal food [RF]) was superior to an adult maintenance food (MF) in minimizing uremic crises and mortality rate in dogs with spontaneous chronic renal failure. DESIGN: Double-masked, randomized, controlled clinical trial. ANIMALS: 38 dogs with spontaneous chronic renal failure. PROCEDURE: Dogs were randomly assigned to a group fed adult MF or a group fed RF and evaluated for up to 24 months. The 2 groups were of similar clinical, biochemical, and hematologic status. The effects of diets on uremic crises and mortality rate were compared. Changes in renal function were evaluated by use of serial evaluation of serum creatinine concentrations and reciprocal of serum creatinine concentrations. RESULTS: Compared with the MF, the RF had a beneficial effect regarding uremic crises and mortality rate in dogs with mild and moderate renal failure. Dogs fed the RF had a slower decline in renal function, compared with dogs fed the MF. CONCLUSIONS AND CLINICAL RELEVANCE: Dietary modifications are beneficial in minimizing extrarenal manifestations of uremia and mortality rate in dogs with mild and moderate spontaneous chronic renal failure. Results are consistent with the hypothesis that delay in development of uremic crises and associated mortality rate in dogs fed RF was associated, at least in part, with reduction in rate of progression of renal failure.     

The Effect of Combined Therapy With Captopril, Furosemide, and a Sodium-Restricted Diet on Serum Electrolyte Concentrations and Renal Function in Normal Dogs and Dogs With Congestive Heart Failure

Captopril, furosemide, and a sodium-restricted diet were administered to 6 normal dogs and 10 dogs with congestive heart failure. Serum electrolyte concentrations and renal function were monitored in both groups. In the normal dogs, no clinically meaningful changes in serum electrolyte, urea nitrogen, or creatinine concentrations developed during therapy with a sodium-restricted diet and 4 weeks each of furosemide alone, captopril alone, or furosemide plus captopril. Three of 6 normal dogs on furosemide and a sodium-restricted diet had at least one serum potassium concentration above the reference range during the 4 weeks of observation. One normal dog on captopril, furosemide, and a sodium-restricted diet developed azotemia, and 2 dogs had serum potassium concentrations above the reference range during the 4 weeks of observation. Ten dogs with congestive heart failure were treated with captopril, furosemide, a sodium-restricted diet, and digoxin.
Etiopathogenesis of the heart failure included valvular insufficiency (n = 6), dilated cardiomyopathy (n = 3), and dilated cardiomyopathy and dirofilariasis (n = 1). Serum electrolyte concentrations and renal function were monitored for 5 consecutive weeks in 7 of the 10 dogs and for 17 weeks or longer in 6. Two dogs were euthanized after 4 weeks because of acute decompensation of heart failure, and one dog developed severe azotemia and uremia. Six of 10 dogs with congestive heart failure had at least one serum potassium concentration above the reference range sometime during the 5 weeks of observation, although the changes in the mean serum potassium concentrations were not statistically significant. Four of 10 dogs with congestive heart failure developed azotemia sometime during the 5 weeks of observation.     

Dietary management of canine and feline chronic renal failure

Nutritional therapy is the mainstay of management of chronic renal failure in dogs and cats. Diets designed for use in renal failure are typically reduced in protein, phosphorus, and sodium content. These and other dietary modifications are designed to prevent or ameliorate clinical signs of uremia, minimize disturbances associated with excesses or losses of electrolytes and minerals, arrest or retard progression of renal failure, and maintain adequate nutrition.     

New form of X-linked dominant hereditary nephritis in dogs

OBJECTIVE: To determine features of a new form of hereditary nephritis (HN) in dogs. ANIMALS: Parents and 16 first-generation offspring (8 males, 8 females). PROCEDURE: Adolescent dogs that developed renal failure were euthanatized and necropsied. Unaffected dogs were monitored until they were at least 2 years old. Studies included light and electron microscopy of kidneys obtained from affected and unaffected dogs and immunolabeling for collagen-IV chains in renal and epidermal basement membranes (BM). The nucleotide sequence of a portion of exon 35 of the COL4A5 gene was determined in genomic DNA isolated from affected and unaffected males. RESULTS: 7 of 8 male and 2 of 8 female offspring had proteinuria and juvenile-onset chronic renal failure, which progressed more rapidly in the males. Labeling for alpha3-alpha6(IV) chains was completely absent in renal BM of affected males and segmentally absent in affected females. Expression of alpha1-alpha2(IV) chains in glomerular BM (GBM) of affected dogs was increased. Labeling for alpha5-alpha6(IV) chains in epidermal BM was absent in affected males and segmental in affected females. Ultrastructural changes characteristic of HN were observed in GBM of affected dogs. The sequence of exon 35 of COL4A5 was normal in affected dogs. CONCLUSIONS: This renal disease is an example of X-linked dominant HN, with typical abnormalities of GBM ultrastructure and alpha(IV) chain expression. CLINICAL RELEVANCE AND IMPLICATIONS FOR HUMAN MEDICINE: Dogs with this naturally acquired progressive renal disease can be used to investigate the pathogenesis and treatment of similar disorders in human beings and dogs.     

Genotype identification and prevalence of Giardia duodenalis in pet dogs of Guangzhou, Southern China

Giardia duodenalis is a flagellated parasite and is considered one of the most common causes of protozoal diarrhea in both humans and animals worldwide. This paper represents the first study of the prevalence of G. duodenalis in pet dogs in Guangzhou, China. Faecal samples (209 specimens) were obtained from young (<6 months old), adult (6 months to 3 years) and elder dogs (>3 years old). 8.61% (18/209) faecal samples were recorded positive using microscopy examination, and 11.00% (23/209) using PCR. The prevalence was significantly higher in diarrheic dogs (26.31%) compared with non-diarrheic dogs (5.10%), while it was higher in young (25.58%) than both adult (7.37%) and elder (7.04%) dogs and the difference was statistically significant (P<0.05). The prevalence in male dogs 11.30% (13/115) was higher than females 10.87% (10/92), and in suburban dogs (12.15%) higher than urban 9.80%, but the difference was not statistically significant (P>0.05). Sequence analysis of the 23 PCR-positive samples revealed the presence of Assemblage D (18/23), and zoonotic Assemblage A (5/23). The present investigation reported a high infection rate of G. duodenalis in pet dogs, especially in young dogs. Genotypic characterization demonstrated that the zoonotic Assemblage A was found, a fact that poses a potential risk of G. duodenalis transmission from pet dogs to humans. It is suggested that pet owners should take appropriate hygiene measures to prevent and control giardiasis in this region.     

Prevalence of antimicrobial-resistant staphylococci in nares and affected sites of pet dogs with superficial pyoderma

Currently, antimicrobial-resistant staphylococci, particularly methicillin-resistant Staphylococcus pseudintermedius (MRSP), are frequently isolated from canine superficial pyoderma in Japan. However, little is known regarding the nasal prevalence of MRSP in pet dogs. Here, we determined the prevalence of antimicrobial-resistant staphylococci in nares and affected sites of pet dogs with superficial pyoderma. Of the 125 nares and 108 affected sites of pet dogs with superficial pyoderma, 107 (13 species) and 110 (eight species) staphylococci strains, respectively, were isolated. The isolation rate of S. pseudintermedius from pyoderma sites (82/110 strains, 74.5%) was significantly higher than that from nares (57/107 strains, 53.3%) (P<0.01). Notably, the prevalence of MRSP (18/57 strains, 31.6%) in nares was equivalent to that in pyoderma sites (28/82 strains, 34.1%). Furthermore, the phenotypes and genotypes of antimicrobial resistance in MRSP strains from nares were similar to those from pyoderma sites. Our findings revealed that the prevalence of antimicrobial-resistant staphylococci in the nares of pet dogs with superficial pyoderma is the same level as that in affected sites. Therefore, considerable attention should be paid to the antimicrobial resistance of commensal staphylococci in companion animals.