OBJECTIVE To determine whether dogs with immune-mediated hemolytic anemia (IMHA) had a low plasma mean platelet component (MPC) concentration and whether MPC was associated with outcome.
DESIGN Retrospective case-control study and survival analysis.
ANIMALS 95 dogs with IMHA (cases) as well as 95 healthy dogs and 95 sick dogs without IMHA (controls) matched to cases by age, reproductive status, and breed.
PROCEDURES Plasma MPC concentration at initial examination was compared among groups. For dogs with IMHA only, sex, age, serum urea and bilirubin concentrations, Hct, platelet count, and plasma fibrinogen, D-dimer, and MPC concentrations were evaluated for associations with survival to 42 days after initial examination.
RESULTS Plasma MPC concentration was significantly lower in dogs with IMHA than in the other 2 dog groups. In dogs with IMHA, plasma MPC concentration was the only factor significantly associated with outcome. The optimal plasma MPC concentration cutoff value for predicting nonsurvival of dogs with IMHA was 19.1 g/dL; values ≤ 19.1 g/dL were associated with nonsurvival. Likewise, the survival curve for dogs with plasma MPC concentrations ≤ 19.1 g/dL differed significantly from that for dogs with values > 19.1 g/dL. The mean estimated risk of death for dogs with IMHA decreased by 16% for every unit increase in plasma MPC concentration.
CONCLUSIONS AND CLINICAL RELEVANCE In dogs with IMHA, platelets appeared to have been activated to a greater degree, as determined by lower plasma MPC concentrations, than in healthy dogs or sick dogs without IMHA. Plasma MPC concentration at initial examination may be useful for predicting prognosis in dogs with IMHA.
Objective—To determine whether dogs with ascites secondary to right-sided congestive heart failure (CHF) have bleeding disorders associated with hypofibrinogenemia and discordant plasma fibrin-fibrinogen degradation products (FDPs) and D-dimer assay results (ie, a circulating concentration of FDPs higher than the reference range and a circulating concentration of D-dimer within the reference range).
Design—Retrospective case-control study.
Animals—80 client-owned dogs.
Procedures—Dogs with ascites secondary to right-sided CHF (group 1; n = 20), unhealthy dogs without cardiac disease (group 2; 40), and dogs with left-sided CHF (group 3; 20) were included in the study. Urine bile acids-to-creatinine concentration ratios were calculated as a marker of liver function. Differences among groups regarding coagulation profile analysis results and prevalence of discordant FDPs and D-dimer assay results were determined.
Results—No significant differences were detected among the 3 groups regarding urine bile acids-to-creatinine concentration ratios. Plasma fibrinogen concentration was significantly lower for group 1 versus groups 2 or 3. Prevalence of discordant FDPs and D-dimer assay results was significantly higher for group 1 versus groups 2 or 3. Eighteen group 1 dogs had discordant FDPs and D-dimer assay results. Ten of these dogs had concurrent hypofibrinogenemia, 2 of which had clinical signs of bleeding. Only 10 dogs in groups 2 or 3 had discordant FDPs and D-dimer assay results; none of these dogs had hypofibrinogenemia or clinical signs of bleeding.
Conclusions and Clinical Relevance—Dogs with right-sided CHF and ascites may be at increased risk for primary hyperfibrinogenolysis (ie, hypofibrinogenemia and discordant FDPs and D-dimer assay results).
Objective—To evaluate and validate 3 spectrophotometric assays for measuring serum activity of paraoxonase type-1 (PON1), an enzyme associated with high-density lipoproteins, in dogs.
Animals—22 healthy adult dogs and 10 dogs with eccentrocytosis.
Procedures—2 methods were adapted for use in 96-well microplates with phenyl acetate and 5-thiobutyl butyrolactonase as substrates, and 1 was adapted for use in an automated analyzer with p-nitrophenyl acetate as substrate. Blood samples were collected from all dogs, serum was harvested, and serum PON1 activity was measured with each method.
Results—Imprecision was low for all 3 methods, with the exception of interassay imprecision for 5-thiobutyl butyrolactonase, and results were linear across serial sample dilutions. The 3 methods were able to detect low PON1 activity when EDTA was used for blood sample collection, yielded lower PON1 values in sick dogs with eccentrocytosis than in healthy dogs, and yielded highly correlated results.
Conclusions and Clinical Relevance—The methods described here may allow a wider use of PON1 activity as a biomarker of oxidative stress in dogs in clinical and research settings. Results of each method were robust and precise (with the exception of the interassay values for the lactonase method), and the methods were easy to set up in a laboratory.
Objective—To evaluate the use of EDTA tubes for collection of blood samples for assays of secondary hemostasis in dogs.
Animals—108 dogs of various ages, breeds, and sexes (19 healthy and 89 with abnormalities of secondary hemostasis).
Procedures—Blood samples were collected via cephalic venipuncture and transferred to sodium citrate tubes and EDTA tubes. Plasma was harvested from each type of tube for assays of concentrations of fibrinogen and D-dimer as well as prothrombin time, activated partial thromboplastin time, and antithrombin activity. Intra-assay and interassay precision and correlation coefficients for all hemostatic tests were calculated for each type of plasma sample. The effect of storage conditions on assay results for the 2 types of plasma samples was also evaluated.
Results—Results of hemostatic tests were highly correlated between citrated and EDTA-treated plasma samples. Intra-assay imprecision for all hemostatic tests with the exception of D-dimer concentration was < 10% for both citrated and EDTA-treated plasma samples; interassay imprecision was higher for EDTA-treated versus citrated plasma samples. Storage of plasma samples for 1 hour did not result in significantly different assay results for either type of plasma sample, but storage for 2 hours significantly affected values for EDTA-treated plasma samples.
Conclusions and Clinical Relevance—Although evaluation of the sensitivity and specificity of hemostatic tests that use EDTA-treated plasma samples is required, EDTA may be a suitable alternative to sodium citrate as an anticoagulant for use in hemostatic testing in conditions in which tests could be performed within 1 hour after sample collection.
The aim of the study was to evaluate whether the tactile stimulation of the perigenital region together with manual bladder expression (MBE) facilitated the urine stream in cats with acute or chronic upper motor neuron injury (UMNI).
34 cats with UMNI having urinary retention.
All the cats had a complete neurologic examination, which determined the localization of the UMNI between T3 and L3. They were classified as chronic UMNI if the injury had occurred more than 3 days previously. The cats were divided equally into 2 groups: the M group (n = 17) managed with only MBE, and the MT group (17) managed with MBE and tactile stimulation.
In both groups, all the cats affected by chronic UMNI resumed urination. The time required to obtain a urine stream in the chronic UMNI was 9.3 seconds in the M group and 3.1 seconds in the MT group (P < .05). In the cats affected by acute UMNI, a urine stream was achieved in 54% of the M group and 100% of the MT group (P < .05). The time to obtain a urine stream in the acute UMNI cats was 7.8 seconds in the M group and 3.75 seconds in the MT group (P < .05).
Adding tactile stimulation of the perigenital region to the MBE improved the urine stream in cats affected by UMNI.