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Background: The Platelet function analyzer‐200 (PFA‐200) can determine the effect of clopidogrel in cats, but analysis traditionally must be performed at point‐of‐care (POC). The ability to ship samples of blood to a laboratory would allow widespread access. Objectives: We aimed to validate the shipping of blood samples for PFA‐200 analysis in cats to determine the effect of clopidogrel. Methods: Twenty healthy cats and 10 cats receiving clopidogrel were recruited. Blood was collected from cats and aliquoted into two samples, one was analyzed at POC within 2 hours using the PFA‐200, and the other was packaged and transported to a location 4 km away, stored, and transported back to the lab for analysis the following day. Results: Median closure times (CTs) with the collagen/adenosine diphosphate (COL/ADP) cartridge in healthy cats were 51.5 seconds (POC) and 78.8 seconds (shipped), which were significantly different (P < 0.001), and for cats on clopidogrel, median CTs were 147.5 seconds (POC) and 190 seconds (shipped), which were not significantly different (P = 0.131). Median CTs with the P2Y cartridge in healthy cats were 50.5 seconds (POC) and 64.9 seconds (shipped), which were significantly different (P = 0.03), and in cats receiving clopidogrel, median CTs were 300 seconds (POC) and 300 seconds (shipped) which were not significantly different (P = 1.000). Reference intervals for CTs differed for COL/ADP at POC (19.8–89.7 seconds) and shipped (50.9–161.6 seconds) and for P2Y at POC (35.5–118.8 seconds) and shipped (35.1–108.9 seconds). Receiver operating characteristics showed similar areas under the curve (AUCROCs) regarding the effect of clopidogrel for COL/ADP at POC (0.994 seconds) and shipped (0.932) and for P2Y at POC (0.904 seconds) and shipped (0.975 seconds). When classifying for the presence of clopidogrel effects, Cohen's Kappa was 0.62 for COL/ADP and 1.00 for P2Y. Conclusions: Shipping blood samples for PFA analysis are feasible with similar performance to POC analyses for determining the effect of clopidogrel in cats. [ABSTRACT FROM AUTHOR]

Background: The Platelet function analyzer‐200 can determine the effect of clopidogrel in cats. Flow obstruction is an error that causes uninterpretable results. Closure curves and parameters initial flow rate (IF) and total volume (TV) are displayed by the PFA‐200 and may allow interpretation of results in cases of flow obstruction. The primary hemostasis components (PHC) are calculated values that normalize these parameters. Objectives: To determine if closure curves and research parameters allow detecting the effect of clopidogrel in cases of flow obstruction. Methods: A review of closure curves identified those with flow obstruction and paired analysis that did not. Non‐flow–obstructed curves were used to categorize curves with respect to clopidogrel effects. IF, TV, PHC(1), and PHC(2) were evaluated to determine if these could be used to categorize if a sample exhibited the effects of clopidogrel. Curves were visually analyzed, and characteristics identified that were more common with or without the effect of clopidogrel. Visual analysis of curves was performed by blinded observers to determine if a visual analysis was able to predict the effect of clopidogrel. Results: Analysis of parameters was able to predict closure or non‐closure in flow‐obstructed curves. TV, PHC(1), and PHC(2) had area under the curve of the receiver operating characteristics of 0.79, 0.79, and 0.87. Visual curve analysis was unable to predict closure, with an average accuracy of only 55%, among three reviewers. Agreement between reviewers was poor (Fleiss' Kappa 0.06). Conclusions: Visual curve analysis was unable to determine the effect of clopidogrel in flow‐obstructed samples. Numerical parameters were able to detect the effect of clopidogrel with a high degree of accuracy in flow‐obstructed samples. [ABSTRACT FROM AUTHOR]

Background: The performance of commercial point‐of‐care crossmatch (CM) tests compared to laboratory tube agglutination CM is unknown. Additionally, there is limited information regarding CM incompatibility in ill dogs. Objectives: To determine if point‐of‐care major CM methods are accurate in detecting compatible and incompatible tests when compared to laboratory CM methods, and to identify factors associated with CM incompatibility in dogs. Animals Part 1 (prospective) included 63 client‐owned dogs potentially requiring blood transfusion. Part 2 (retrospective) included all dogs from part 1, plus medical records of 141 dogs with major CM results. Methods: For part 1, major CM was performed using a tube agglutination assay (LAB‐CM), a gel‐based point‐of‐care test (GEL‐CM), and an immunochromatographic point‐of‐care test (IC‐CM). For part 2, medical record data were collected to determine rates of and risk factors for CM incompatibility. Results: Kappa agreement between the LAB‐CM and GEL‐CM methods could not be calculated due to a relative lack of incompatible results. Kappa agreement between the LAB‐CM and IC‐CM methods was 0.16 (95% confidence interval [CI] = 0‐0.31, P =.007) indicating no agreement. The LAB‐CM incompatibility in transfusion‐naïve vs dogs that had a transfusion was 25% and 35%, (P =.3). Conclusions and Clinical Importance: Compared to laboratory methods, point‐of‐care methods evaluated in our study lacked sensitivity for detecting incompatibilities. Dogs had similar rates of major CM incompatibility regardless of transfusion history. This suggests CM testing prior to transfusion be considered in all dogs however our study did not investigate clinical relevancy of incompatible LAB‐CM. [ABSTRACT FROM AUTHOR]

Objectives The objective was to determine if decreased platelet function could be detected after treatment with aspirin and/or clopidogrel in healthy cats using three point-of-care platelet function tests that evaluate platelet function by different methods: Multiplate (by impedance), Platelet Function Analyzer 100 (by mechanical aperture closure) and Plateletworks (by platelet counting). Methods Thirty-six healthy cats were randomly assigned to receive one of three oral treatments over an 8 day period: (1) aspirin 5 mg q72h; (2) aspirin 20.25 mg q72h; or (3) clopidogrel 18.75 mg q24h. Cats treated with 5 and 20.25 mg aspirin also received clopidogrel on days 4–8. Platelet aggregation in response to adenosine diphosphate and collagen ± arachidonic acid was assessed on days 1 (baseline), 4 and 8. Aspirin and clopidogrel metabolites were measured by high-performance liquid chromatography. Platelet function in response to treatment was analyzed by ANCOVA, linear regression and Spearman correlation. Results The only solitary aspirin effect was detected using Plateletworks with collagen in cats treated with 20.25 mg. The only effect detected by Multiplate was using arachidonic acid in cats treated with both aspirin 20.25 mg and clopidogrel. All clopidogrel treatment effects were detected by Platelet Function Analyzer 100, Plateletworks (adenosine diphosphate) and Plateletworks (collagen). Drug metabolites were present in all cats, but concentrations were minimally correlated to platelet function test results. Conclusions and relevance Platelet Function Analyzer 100 and Plateletworks using adenosine diphosphate ± collagen agonists may be used to detect decreased platelet function in response to clopidogrel treatment. Either aspirin is not as effective an antiplatelet drug as clopidogrel, or the tests used were not optimal to measure aspirin effect. Cats with heart disease are commonly prescribed antiplatelet drugs to decrease the risk of aortic thromboembolism. Platelet Function Analyzer 100 and Plateletworks may be useful for confirming clopidogrel treatment in these cats. [ABSTRACT FROM AUTHOR]

The article presents a case study of a disseminated algal infection reported in a young rough-coated collie dog with progressive neurologic deficits, blindness, and hemorrhagic diarrhoea. Topics discussed include prototheca zopfii organisms cultured from feces, urine, and blood of the dog, ophthalmic examination showing a negative dazzle reflex and menace response, and necropsy results showing granulomas containing typical organisms within the proximal colon, heart, and eyes.

The article describes a study which investigated the use of lithium carbonate to prevent lomustine-induced myelosuppression among beagles. Lomustine is a cytotoxic drug which is a dog treatment for neoplasms while lithium (Li) is a hematopoietic stimulant. The study results revealed that the dogs developed neutropenia after the lomustine treatment and the platelet concentrations decreased even with Li. The study also showed that Li mildly stimulated granulopoiesis and thrombopoiesis.

The article focuses on a study which investigated the use of vascular access ports (VAPs) for feline blood collection. Phlebotomists perform jugular venipuncture in feline blood donation but resulting to hypotension due to blood loss and anesthesia. The study results showed dermatologic complications like seromas, pruritus and moist dermatitis. Sampling occlusion was another complication of the study due to catheter kinking, thrombosis and catheter wall collapse from negative pressure. Overall, the study revealed that using VAPs is technically feasible.

The article discusses a study which examined the use of a questionnaire to determine hemorrhagic signs and their value as a predictor of von Willebrand disease (vWD) in a population of dogs. It assessed the hemorrhagic signs for 165 canine participants using a standard questionnaire. Findings showed no visually identifiable pattern in the raw data which makes the diagnostic profile unsuccessful in predicting the risk of hemorrhage.

The article discusses a study which investigated the association between assays of inflammation and coagulation in dogs affected with an illness requiring admission to an intensive care unit (ICU). Coagulation and inflammation are thought to intersect through coagulation activation, down-regulation of natural anti-coagulants and inhibition of fibrinolysis. Dogs with naturally occurring disease requiring admission to a tertiary referral ICU were chosen for the study. Findings showed the strongest correlation between activated clotting time (ACT) and C-reactive protein (CRP). They indicate that with higher concentrations of CRP, the associated ACT values were prolonged.

A case of a disseminated algal infection is reported in a young rough-coated collie dog with progressive neurologic deficits, blindness, and hemorrhagic diarrhea. Prototheca zopfii organisms were cultured from feces, urine, and blood. At necropsy, granulomas containing typical organisms were identified within the proximal colon, heart, kidneys, and eyes.

Background: Commonly used 11 or 13ga needles are relatively large for collection of bone marrow (BM) biopsies from small dogs., Objectives: The aims of this study were to assess ease of BM collection and quality of specimens obtained from small dogs using 13 and 15ga needles and to determine if specimen encasement would improve quality., Methods: Humeral and iliac biopsies obtained from 17 Beagle dogs with a 15ga needle and a power driver were compared with humeral biopsies obtained with a 13ga Jamshidi needle. Ease of collection (scored as 1 [very difficult] to 5 [very easy] for 3 components of collection with scores summed), section quality (scored as 1 [poor] to 5 [good]), and lesions at collection sites were scored. Quality of additional humeral biopsies obtained with a 15ga needle and wrapped in tissue paper prior to fixation was assessed., Results: Use of a 15ga needle to obtain a humeral BM biopsy was significantly easier (mean score ± SD = 13.6 ± 1.7) than obtaining humeral BM using a 13ga needle (11.4 ± 1.6; P < .001) or obtaining iliac BM using a 15ga needle (10.9 ± 2.0, P < .001). Quality of humeral biopsies obtained with a 13ga needle (3.9 ± 1.2) was better than for biopsies of the humerus (1.9 ± 1.3, P < .001) or ilium (1.4 ± 0.6, P < .001) using a 15ga needle. Only sites sampled with a 13ga needle were identifiable grossly after the procedure. In most biopsies, cell density and cellularity were lower when a 15ga needle was used. Paper-wrapping of biopsies did not improve quality., Conclusions: In small dogs, collection of humeral BM biopsies using a 15g needle is feasible and more easily accomplished than collection using a 13ga needle. Hematopoiesis may be underestimated in specimens collected using the smaller needle., (© 2012 American Society for Veterinary Clinical Pathology.)

Background: Thrombelastographic (TEG) analysis is a test of global hemostasis in veterinary medicine; however, there have been limited comparisons of analysis of citrated native and kaolin-activated samples., Objectives: The purpose of this study was to determine the variation in TEG variables between citrated native and kaolin-activated whole blood samples and to establish reference intervals for both sample types., Methods: Citrated whole blood samples were obtained from 40 healthy dogs. Thirty minutes after collection, TEG analysis was performed simultaneously on samples with and without kaolin-activation. Reaction time (R), clotting time (K), angle (α), maximum amplitude (MA), global clot strength (G), and clot lysis at 30 minutes (LY30) were recorded, and the concordance correlation coefficient (ρ(c)) was calculated for each sample type., Results: Significant differences between results obtained for kaolin-activated and native samples were obtained for R (mean difference -1.3 minute, P = .0009), K (-0.7 minute, P = .0003), α (+5.1º, P = .002), MA (+2.4 mm, P = .002), and G (+568 dyn/cm(2), P = .0009). LY30 was not different between methods. There was substantial agreement between methods for G (ρ(c) = .69) and MA (ρ(c) = .65), moderate agreement for R (ρ(c) = .45) and α (ρ(c) = .44), fair agreement for K (ρ(c) = .29), and slight agreement for LY30 (ρ(c) = .04)., Conclusions: The TEG variables were significantly altered by kaolin activation; however, some agreement between sample types suggests a consistent bias. In citrated whole blood activated with kaolin, clot formation time is shortened and the amplitude of the tracing is increased, resulting in a TEG tracing that appears to indicate relative hypercoagulability compared with that obtained using native citrated whole blood samples., (© 2012 American Society for Veterinary Clinical Pathology.)

A 12-year old, castrated male domestic shorthair cat presented with a 2-year history of poor hair coat, seborrhea, generalized pruritus and otitis externa. Low circulating concentrations of total serum thyroxine (TT(4)) and free thyroxine (fT(4)) and an elevated thyroid stimulating hormone concentration supported a diagnosis of primary hypothyroidism. Thyroid scintigraphy did not show uptake of radioactive technetium in the thyroid area. Treatment with levothyroxine resulted in clinical improvement. Recurrence of dermatitis 8 months after onset of treatment resulted in euthanasia of the cat. On post-mortem examination, thyroid tissue was not identified on gross or histological examination. Pituitary immunohistochemistry identified hyperplasia of chromophobe cells., (Copyright 2009 ESFM and AAFP. Published by Elsevier Ltd. All rights reserved.)

The objective of the study was to investigate the value of additional tests [platelet count, partial thromboplastin time (PTT), platelet function analysis using the PFA-100, Collagen binding assay (vWF:CBA), and Factor VIII activity], for use in conjunction with the von Willebrand factor antigen enzyme-linked immunosorbent assay (ELISA), as part of a newly developed diagnostic profile for improved characterization of patients with von Willebrand disease (vWD). The study population included 183 clinically healthy canines ranging in vWF:Ag concentration from 1% to 125%. The Asserachrom vWF:Ag ELISA assay was used as an external control for the determination of vWD status. Degree of association between the additional tests and vWF concentration was evaluated, and associations between the additional tests were also assessed, including their ability to distinguish dogs with vWD from those without vWD. In addition, a reference interval was determined for the PFA-100 platelet function analyzer. Strong associations were found between the PFA-100, vWF:CBA, and Asserachrom vWF:Ag assay, and a significant association was found between the PFA-100 and vWF:CBA. An association was detected between Factor VIII activity and the Asserachrom vWF:Ag assay, the vWF:CBA and the PFA-100; however, a corresponding pattern was not visually apparent in the raw data, making the association clinically irrelevant. The association between the platelet count and the PTT with the other additional tests was negligible. Based on our results, the vWF:CBA and PFA-100 would be valuable assets, in conjunction with a vWF:Ag assay, in a canine vWD diagnostic profile to further characterize patients with this disease.

Currently, the pathogenic role of Ehrlichia canis in cats has been proposed predominantly on the basis of the serologic evidence of natural infection and the infrequent detection of morulae-like structures within the cytoplasm of leukocytes in cats. The purpose of this report was to provide molecular evidence supporting E. canis-like infection in 3 cats that had clinical manifestations consistent with canine ehrlichiosis but lacked antibodies to E. canis antigens. Serum from all 3 cats contained antinuclear antibodies (ANAs). The predominant disease manifestation was polyarthritis in 1 cat and bone marrow hypoplasia or dysplasia. accompanied by pancytopenia or anemia and thrombocytopenia, in 1 cat each. The alignment of E. canis partial 16S ribosomal DNA (rDNA: 382 nucleotide positions), amplified from EDTA blood samples from each cat, was identical to each other and was identical to a canine isolate of E. canis (GenBank accession number AF373613). In 1 cat, concurrent treatment with corticosteroids may have interfered with the therapeutic effectiveness of doxycycline for the elimination of E. canis-like infection. To further define the spectrum of ehrlichiosis in cats, polymerase chain reaction (PCR) testing may be necessary until serologic testing is thoroughly validated in experimentally or naturally infected cats. In addition, until E. canis has been isolated from cats and several tissue culture isolates are available from disparate geographic regions for detailed comparative genetic study, the molecular evidence presented in this study supporting E. canis-like infection in cats must be interpreted with caution.

Hematopoietic stem cell (HSC) gene therapy will require efficient transfer of genes to HSCs and long term engraftment and proliferation of genetically modified HSCs following adoptive transfer. We evaluated whether fractionation of grafts into 4-5 weekly infusions to non-myeloablated, autologous canine recipients would improve engraftment of genetically modified HSCs. Experimental animals and controls receiving a single infusion had similar levels of engraftment with approximately 3-10% of marrow derived progenitors carrying transgene sequences for up to 29 months. There appears to be no improvement of engraftment of genetically modified HSCs in non-myeloablated large animal recipients by dose fractionation.