When a functional deficiency of AT is suspected it is necessary to determine whether there is a type I deficiency (reduced synthesis) or type II deficiency (synthesis of an abnormal protein). When a type II deficiency is confirmed further assays can be requested to fully characterise the deficiency as different mutations may carry varying thrombotic risk.
Tube
Coagulation Tube
05 (CP) – Citrate
Availability
Weekly
Additional Information
When a borderline or low level of antithrombin activity is detected, AT antigen is normally assayed to determine if the patient has a type I or II defect/deficiency. A repeatedly low ratio of AT activity/antigen can indicate the presence of a type II AT mutation capable of causing type II deficiency even in the absence of AT deficiency in the individual tested.
Turnaround Time
14 days
Send to
Specialist Coagulation
Chancellor / Lincoln Wing Link Corridor
Pathology
Block 32
St James University Hospital
Beckett Street
Leeds
LS9 7TF
Contact
Link to Advice
OR Haemostasis/Haematology Consultant
Collection Con
1 x citrate sample filled to the line please. 2 x citrate samples if further investigations are required. Samples must be processed within 6 hours.
Frequency
Weekly
Sample REQ
Blood
Sample Storage REQ
Plasma aliquots from primary samples (post-analysis) stored frozen at -20 degrees – 1 month or -80 degrees for 2 months (Specialist Coagulation Assays SJUH)
Ref. Range (Male)
0.83 – 1.24 iu/mL
Ref. Range (Female)
0.83 – 1.24 iu/mL
Units
iu/mL
IP Acute TAT
N/A
IP Routine TAT
N/A
GP Acute TAT
N/A
GP Routine TAT
N/A