Thromboelastographic platelet mapping in dogs with complicated Babesia rossi infection

Abstract

Background: Dogs with Babesia rossi infection display a normocoagulable thromboelastogram, despite being markedly thrombocytopenic, which is purportedly due to large-scale platelet activation. Thromboelastographic platelet mapping (TEG-PM) evaluates individual contributions of thrombin, fibrinogen, and platelets to clot formation, and may elucidate some of the pathomechanisms of thrombocytopeniaassociated hemostatic alterations. Objective: This study investigated potential differences in TEG-PM variables in dogs with complicated B rossi infection compared with healthy controls, and whether these variables correlated with platelet activation indices. Methods: The maximum amplitude (MA) following thrombin generation (MA Thrombin ) was determined using kaolin-activated TEG. The TEG-PM variables included MA following the addition of platelet agonists arachidonic acid (MA AA ) and adenosine diphosphate (MA ADP ), and MA due to fibrin alone (MA Fibrin ). In addition, platelet indices and fibrinogen concentrations were determined. Results: Thirteen dogs with complicated B rossi infection and five healthy controls were included. The median MA Fibrin and fibrinogen concentrations were significantly higher (P < 0.01 for both) and median platelet count was significantly lower (P < 0.01) in the babesiosis group vs the control group. No significant differences were found for MA Thrombin and MA AA/ADP . maximum amplitude due to fibrin alone was positively correlated with fibrinogen concentration (r = 0.735), mean platelet volume (r = 0.517), and mean platelet mass (r = 0.498), and negatively correlated with hematocrit (r = −0.685), platelet count (r = −0.476), and plateletcrit (r = −0.479) (P < 0.05 for all). Conclusions:This study suggests that the presence of hyperfibrinogenemia offsets the severe thrombocytopenia associated with B rossi to result in normal thromboelastograms and lack of overt clinical bleeding. K E Y W O R D Sdogs, hyperfibrinogenemia, MA Fibrin , thrombocytopenia

Diagnostic Value of Thromboelastography (TEG) for the Diagnosis of Death in Infected Patients

“…The MA reflects the fibrin/platelet clot’s maximum strength and is influenced by platelet and Fbg factors. 31 (1) When the MA decreases, the patient’s blood is diluted and prone to bleeding; (2) the patient’s body is deficient or depleted in clotting factors; and (3) abnormalities in the quality or quantity of platelets occur. 32 , 33 When MA increases, it means that the patient’s blood is in a hypercoagulable state and is prone to arterial and venous thrombosis.…”