Eurofins Biomnis code

TCA

Synonyms

• APTT
• APTT, activated partial thromboplastin time
• TCK

Specialty

Haematology

Clinical significance

Activated Partial Thromboplastin Time (aPTT) is the time taken for platelet-depleted, citrated plasma to coagulate in the presence of phospholipids (cephalin) and a contact activator (e.g. kaolin, celite, silica or ellagic acid).A prolonged aPTT can indicate deficiency in any of a number of contact coagulation-related factors (high molecular weight kininogen, prekallikrein or Factors XII or XI) or other factors (IX, VIII, X, V, II), or it can be due to very low levels of functional fibrinogen.

Preanalytics

• 2 mL :
• Citrated Plasma
•   FROZEN
• Freezing within 4 hours

• A tube specifically for this analysis : No

Further information

If possible, please specify if the patient is on an anticoagulant treatment as well as the clinical context.
In case of investigation of a prolonged aPTT without further information, a measurement of factors VIII, IX, XI will be performed in addition to aPTT. In a pre-surgical context, investigation for circulating anticoagulant is limited to aPTT, aPTT patient + control, and calculation of the Rosner index.
It is advisable to send us a frozen and centrifuged citrate sample in compliance with the GFHT pre-analytical recommendations.

Methodology

Chronometric method

Turnaround time

1 day