Articles on Medical Diseases and Conditions

Entries Tagged ‘APTT’

Anticoagulant Systems

Coumarin anticoagulants Liver cells produce certain coagulation factors that require vitamin K for synthesis into a form that can be activated. Drugs of the coumarin family inhibit vitamin K utilization by liver cells. The vitamin K–dependent factors, listed in order of decreasing sensitivity to coumarin, are factor VII, factor IX, factor X, and prothrombin. Factor […]

Coagulation Tests in Newborns

The APTT is elevated in the newborn compared to the adult reference range. At least in part this is due to reduction of 30%-50% in activity of factors XI, XII, HMWK, and Fleher Factor. Activity is even lower in premature infants. Adult values are reached in 3-6 months. Vitamin K–dependent factors are reduced to 20%-60% […]