Procoagulant Microparticles in Dogs with Immune‐Mediated Hemolytic Anemia. (13th April 2015)

• Record Type: Journal Article
• Authors: Kidd, L.; Geddings, J.; Hisada, Y.; Sueda, M.; Concannon, T.; Nichols, T.; Merricks, E.; Mackman, N.
• Is Part Of: Journal of veterinary internal medicine. Volume 29:Number 3(2015:May/Jun.)
• Page Start: 908
• Page End: 916
• Publication Date: 2015-04-13
• Subjects: Veterinary medicine -- Periodicals; 636.0896
• DOI: 10.1111/jvim.12583
• Languages: English
• ISSNs: 0891-6640

Abstract

<abstract abstract-type="main" id="jvim12583-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="jvim12583-sec-0001" sec-type="section"> <title>Background</title> <p>Studies of some human prothrombotic diseases suggest that phosphatidylserine‐positive (PS+) and tissue factor‐positive (TF+) microparticles (MPs) might play a role in the pathogenesis of thrombosis or serve as biomarkers of thrombotic risk.</p> </sec> <sec id="jvim12583-sec-0002" sec-type="section"> <title>Hypothesis/Objectives</title> <p>To determine if circulating levels of PS+MP and procoagulant activity (PCA) associated with PS+MPs and TF+ MPs are increased in dogs with IMHA.</p> </sec> <sec id="jvim12583-sec-0003" sec-type="section"> <title>Animals</title> <p>Fifteen dogs with primary or secondary IMHA and 17 clinically healthy dogs.</p> </sec> <sec id="jvim12583-sec-0004" sec-type="section"> <title>Methods</title> <p>Prospective case‐controlled observational study. Circulating PS+MPs were measured by flow cytometry. PCA associated with PS+MPs and TF+MPs was measured by thrombin and Factor Xa generating assays, respectively.</p> </sec> <sec id="jvim12583-sec-0005" sec-type="section"> <title>Results</title> <p>Circulating numbers of PS+MPs were not significantly higher in dogs with IMHA [control median 251, 000/μL (36, 992–1, 141, 250/μL); IMHA median 361, 990/μL (21, 766–47, 650, 600/μL) <italic>P</italic> = .30]. However, PS+MP PCA [control median 2.2 (0.0–16.8) nM PS eq; IMHA median 8.596, (0–49.33 nM PS eq) <italic>P</italic> = .01] and TF+MP PCA [control median 0.0, (0.0–0.0 pg/mL); IMHA median 0.0; (0–22.34 pg/mL], <italic>P</italic> = .04) were increased. Intravascular hemolysis, which we showed might increase PS+ and TF+MP PCA, was evident in 3 of 5 dogs with PS+MP PCA and 2 of 4 dogs with TF+MP PCA higher than controls. Underlying disease in addition to IMHA was detected in 1 of 5 dogs with PS+PCA and 3 of 4 dogs with TF+MP PCA higher than controls.</p> </sec> <sec id="jvim12583-sec-0006" sec-type="section"> <title>Conclusions and Clinical Importance</title> <p>TF+ and PS+MP PCA is increased in some dogs with IMHA. Further studies that determine if measuring TF+ and PS+ MP PCA can help identify dogs at risk for thrombosis are warranted.</p> </sec> </abstract>