title: [The effect of factor VIII:C activity on the activated partial thromboplastin time (aPTT) in the dog. Adaptation of the aPTT as a screening test for canine hemophilia A?].
abstract: The factor VIII:C-sensitivity of the aPTT in dogs was investigated for 2 different, commercially available reagents. For this purpose, 45 plasmas with a decreased factor VIII:C-activity, which were collected from haemophilic dogs (n = 10) at variable points of time of a substitution therapy were used. Moreover, by the stepwise addition of a canine factor VIII:C-deficient plasma to a reference pool plasma it was examined whether factor VIII:C-sensitivity could be increased by prediluting the plasma. By use of both reagents all 45 pathological plasmas (factor VIII:C-activity: 1.5-58%, reference values: 63-144%) showed a prolonged aPTT in relation to the respective reference values. The aPTT correlated well with a pathologically decreased factor VIII:C-activity. In conclusion, the aPTT measured with commercially available reagents according to the manufacturers' instruction is a well suited screening test for haemophilia A and monitoring of its therapy in dogs. Predilution of the dog plasma used in the test does not lead to a distinct of the sensitivity. On the contrary, a high dilution leads to a decrease of sensitivity.
authors.affiliation: Klinik für kleine Haustiere, Tierärztlichen Hochschule Hannover.
authors.forename: R
authors.initials: R
authors.lastname: Mischke
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000175:diagnosis*; D004285:Dogs; D005169:Factor VIII / Q000032:analysis*; D006467:Hemophilia A / Q000175:diagnosis / Q000662:veterinary*; D010314:Partial Thromboplastin Time / Q000662:veterinary*; D012016:Reference Values
chemical_list: D005169:Factor VIII
vernacular_title: Einfluss der Faktor-VIII:C-Aktivität auf die aktivierte partielle Thromboplastinzeit (aPTT) beim Hund.--Eignung der aPTT als Screeningtest für die canine Hämophilie A?