Comparison of signalment, clinicopathologic findings, histologic diagnosis, and prognosis in dogs with glomerular disease with or without nephrotic syndrome.

BACKGROUND: Nephrotic syndrome (NS) develops most commonly in people with glomerular diseases associated with marked albuminuria. Hypernatremia, hypertension, and progressive renal failure are more prevalent in nephrotic than nonnephrotic human patients. HYPOTHESIS/OBJECTIVES: Dogs with NS have higher serum cholesterol, triglyceride, and sodium concentrations, higher urine protein:creatinine ratios (UPC) and systolic blood pressure, and lower serum albumin concentrations than dogs with nonnephrotic glomerular disease (NNGD). NS is associated with membranous glomerulopathy and amyloidosis. Affected dogs are more likely to be azotemic and have shorter survival times. ANIMALS: Two hundred and thirty-four pet dogs (78 NS dogs, 156 NNGD dogs). METHODS: Multicenter retrospective case-control study comparing time-matched NS and NNGD dogs. NS was defined as the concurrent presence of hypoalbuminemia, hypercholesterolemia, proteinuria, and extravascular fluid accumulation. Signalment, clinicopathologic variables, histopathologic diagnoses, and survival time were compared between groups. RESULTS: Age, serum albumin, chloride, calcium, phosphate, creatinine, and cholesterol concentrations, and UPC differed significantly between NS and NNGD dogs. Both groups were equally likely to be azotemic at time of diagnosis, and NS was not associated with histologic diagnosis. Median survival was significantly shorter for NS (12.5 days) versus NNGD dogs (104.5 days). When subgrouped based on serum creatinine (< or ≥1.5 mg/dL), survival of NS versus NNGD dogs was only significantly different in nonazotemic dogs (51 versus 605 days, respectively). CONCLUSIONS AND CLINICAL IMPORTANCE: Presence of NS is associated with poorer prognosis in dogs with nonazotemic glomerular disease. Preventing development of NS is warranted; however, specific interventions were not evaluated in this study.

Cryopreservation of canine platelets.

BACKGROUND: Platelet cryopreservation allows long-term storage and immediate availability of transfusion products. HYPOTHESIS: The addition of a preparation inhibiting platelet activation (Thrombosol, in 2% dimethyl sulfoxide [DMSO]) will enhance in vitro function and prolong in vivo survival of cryopreserved platelets compared with those preserved in 6% DMSO. ANIMALS: Thirty-three research dogs. METHODS: Prospective study. Eleven fresh canine apheresis platelet concentrates (PCs) were each split into 3 units: fresh and cryopreserved in 6% DMSO or Thrombosol. Platelet analysis, performed 1-10 weeks postfreezing, included in vitro functional testing and in vivo survival assessed by administration of biotinylated platelets. RESULTS: Platelet aggregation was diminished in cryopreserved PC. Cryopreserved platelets could be activated, as based on mean thrombin-stimulated P-selectin expression (6% DMSO, 23.0%; Thrombosol, 18.4%), although to a lesser extent than fresh PC (49.1%) (P < .0001). The mean maximum in vivo platelet recovery for fresh PC was 80.3%, significantly greater than recovery for 6% DMSO (49.2%) and Thrombosol PC (43.7%) (P< or = .001). The half-life (days) of fresh PC (3.8 +/- 0.4) was significantly (P < .002) greater than that of 6% DMSO (1.9 +/- 1.0) and Thrombosol (2.4 +/- 1.1) PC, with no difference (P= .3) between cryopreserved PC. CONCLUSIONS AND CLINICAL IMPORTANCE: Cryopreservation of canine platelets using Thrombosol did not provide any advantage over preservation using 6% DMSO. Cryopreserved platelets can be activated in vitro and provide therapeutic benefit when fresh platelets are unavailable. Further studies are needed to assess their in vivo hemostatic function.

Pharmacokinetics of exogenous corticotropin in normal dogs, hospitalized dogs with non adrenal illness and adrenopathic dogs.

Corticotropin (ACTH) pharmacokinetics was assessed in 10 normal dogs receiving exogenous ACTH (0.5 U/kg, i.v.). A two-compartment open model was most appropriate for description of exogenous ACTH pharmacokinetics. The apparent distribution and elimination rate constants (alpha and beta) were 7.4 +/- 2.7 x 10(-2) min(-1) and 5.5 +/- 3.8 x 10(-3) min(-1), respectively. Area under the concentration-time curve (AUC) was 2.91 +/- 0.78 x 10(4) pg x min/mL, mean residence time (MRT) was 45.0 +/- 12.2 min, the distribution half-life (t1/2alpha) was 9.4 min (harmonic mean), and the elimination half-life (t1/2beta) was 128 min (harmonic mean). The total body clearance of ACTH (ClB) was 1.83 +/- 0.46 x 10(4) mL x min/kg and volume of distribution (Vd(area)) was 30 +/- 15 L/kg. Corticotropin pharmacokinetics was also assessed in 12 client owned dogs, six dogs with non adrenal illness (NAI) and six dogs with hyperadrenocorticism (HAC), receiving exogenous ACTH (0.5 U/kg, i.v.). For these patients, data was best fitted to a one-compartment open model. In dogs with NAI, the AUC was 6.23 +/- 0.62 x 10(5) pg x min/mL, MRT was 38.7 +/- 12 min, the apparent elimination rate constant (k(el)) was 0.26 +/- 0.0017 min(-1) elimination half-life was 26.7 min, ClB was 0.84 +/- 0.1 x 10(4) mL/min/kg, and Vd(area) was 31.9 +/- 5.7 L/kg. In dogs with HAC, AUC was 4.74 +/- 0.23 x 10(5) pg x min/mL, MRT was 20.4 min, k(el) was 0.034 +/- 0.009 min(-1), half-life was 20.4 min, CIB was 1.06 +/- 6.0 x 10(4) mL/min/kg and Vd(area) was 29.7 +/- 6.7 L/kg. Dogs with pituitary-dependent hyperadrenocorticism showed more rapid elimination and clearance of exogenous corticotropin than dogs with NAI.

Hospital-acquired acute renal failure in dogs: 29 cases (1983-1992).

OBJECTIVE: To assess factors associated with development of hospital-acquired acute renal failure (HARF) and to determine outcome of and prognostic indicators for dogs with HARF. DESIGN: Retrospective case series. ANIMALS: 29 dogs. RESULTS: The most common inciting causes for developments of HARF were exposure to a nephrotoxicant and advanced age. Mortality was 62%, and factors that contributed to mortality were age and initial urine output. Dogs > or = 7 years old and dogs that were initially oliguric had an odds ratio of mortality of 8.8 and 20, respectively. The effect of preexisting heart disease on mortality approached significance (P = 0.053). The magnitude of azotemia at the time of diagnosis was not related to the chance for survival. Dogs that died had a significantly higher initial anion gap and serum phosphorus concentration than did dogs that survived. We did not detect a relationship between cause of HARF and outcome (survived vs died or euthanatized). CLINICAL IMPLICATIONS: In most cases, HARF is associated with a poor outcome. Older dogs may be at increased risk for development of HARF, and once HARF has developed, have a greater chance of dying. Prognosis can not be determined on the magnitude of azotemia at the time of diagnosis or on the inciting cause of HARF.