DefinitionThis section has been translated automatically.
Acronym for partial thromboplastin time (PTT). Screening test for defects of the endogenous coagulation system (factors XV, XIV, XII, XI, IX, VIII) and the common final coagulation pathway (FX, V, II, I). Prolonged PTT serves as a screening test for lupus anticoagulant (see below phospholipid-antibody syndrome, see below lupus erythematosus, systemic)
General informationThis section has been translated automatically.
- Norm: 20-38 seconds.
- PTT extended:
- haemophilia A or B, phospholipid antibody syndrome
- deficiency of factors II, X, XI, XII, prekallikrein; heparin therapy
- PTT shortened:
- Hypercoagulability
- Thrombocytosis (increase in platelet factor 4).
IndicationThis section has been translated automatically.
- Suspected hemorrhagic diathesis (screening test for endogenous system)
- Monitoring therapy with heparin
- Monitoring of substitution therapy for haemophilia A and haemophilia B
- preoperative screening.
Note(s)This section has been translated automatically.
For therapeutic reasons, heparin low-dose therapy should be prolonged to 1.5-2.0 times its original duration! Low molecular weight heparins (NMH) hardly prolong PTT due to their anti-Xa activity!
Prof. Dr. med. Peter Altmeyer