Thrombin Time
Also written as TT.
His prothrombin time is normal, activated partial thromboplastin time (APTT) is prolonged and thrombin time (TT) is normal.
What our notes say
- His prothrombin time is normal, activated partial thromboplastin time (APTT) is prolonged and thrombin time (TT) is normal. (Haematology End of Year 2025 Past Paper — MKU MBML 3200 Questions & Answers)
- His prothrombin time is normal, activated partial thromboplastin time (APTT) is prolonged, thrombin time (TT) is normal. (Haematology Exam 2025: MCQs on Anaemia, Leukaemia & Clotting)
- Thrombin time evaluates conversion of fibrinogen to fibrin (Internal Medicine End of Semester CAT (MBChB 4): haematology and renal, 30 MCQs )
- Bleeding time tests platelet function, not the intrinsic pathway. (Thrombin time tests the last step, fibrinogen to fibrin.) (Internal Medicine CAT 1 (MBChB 4), 2022: liver, pancreas and bone marrow, 30 MCQ)
- Thrombin time - normal, excluding a fibrinogen abnormality (Haematology End of Year 2025 Past Paper — MKU MBML 3200 Questions & Answers)
- Thrombin time — expected normal, helps exclude fibrinogen abnormalities (Haematology Exam 2025: MCQs on Anaemia, Leukaemia & Clotting)
Study material on Thrombin Time
- Haematology End of Year 2025 Past Paper — MKU MBML 3200 Questions & Answers
- Haematology Exam 2025: MCQs on Anaemia, Leukaemia & Clotting
Practice questions on Thrombin Time
A 20-year-old man presents with recurrent joint bleeds. His prothrombin time is normal, activated partial thromboplastin time (APTT) is prolonged, thrombin time (TT) is normal. Which coagulation factor abnormality is most likely?
- Factor VII deficiency
- Dysfibrinogenaemia
- Factor VIII deficiency (haemophilia A)
- Vitamin K deficiency
Answer: C. An isolated prolonged APTT with normal PT and TT, plus haemarthroses, is classic for haemophilia A. ---