Analysis index

1 ml citrate plasma, frozen (Stability in citrate plasma at 4°C – 8°C: 4 hours)

50% – 150%

Children: Please refer to findings report

• Evaluation of an increased PTT
• Suspicion of hemophilia A (Prevalence 1:10.000, only in males)
• Therapy checks of hemophilia A
• Suspicion of von-Willebrand-syndrome
• Suspicion of acquired factor-VIII-inhibitor (for instance during and after pregnancy and in patients > 60 years of age with newly occurred bleeding tendency)
• Thrombosis tendency

A normal PTT value does not rule out subhemophilia A. Patients with blood group 0 show lower values (between 40 % and 80 %).

Guide to interpretation:

> 150 %: Acute phase reaction, permanently increased activities can be a risk factor for thromboembolic event.

50 % – 150 %: normal hemostasis

25 % – 50 %: Subhemophilia A or von-Willebrand-syndrome, slightly increased risk for bleeding, minor surgery with low risk of bleeding are possible without substitution.

5 % – 25 %: mild hemophilia A or von-Willebrand-syndrome, increased bleeding tendency

1 % – 5 %: moderate hemophilia A or von-Willebrand-syndrome type 3, spontaneous bleeding possible

< 1 %: severe hemophilia A, often spontaneous bleeding (especially intraarticular bleeding)

CAUTION: An acute phase reaction can disguise mild hemophilia or subhemophilia.

For differential diagnosis between hemophilia A and von-Willebrand-syndrome both the von-Willebrand-factor antigen and von-Willebrand-factor activity should be evaluated for the assessment of bleeding tendency.