Coagulation
Coagulation laboratory tests
Antiplasmin assay
Author: Jeremy C. Parsons, M.D.
Last author update: 1 June 2012
Last staff update: 11 September 2020
Copyright: 2002-2023, PathologyOutlines.com, Inc.
PubMed Search: Antiplasmin assay [title]
Cite this page: Parsons JC. Antiplasmin assay. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/coagulationantiplasmin.html. Accessed June 3rd, 2023.
Definition / general
- Also called anti - alpha2 - antiplasmin, plasmin inhibitor
- An uncommon assay usually sent to reference laboratories
- Indications:
- Familial bleeding disorder, after ruling out more common bleeding disorders such as von Willebrand disease
- True alpha2 - antiplasmin deficiency is a rare condition (< 20 cases)
- Most cases are caused by inhibitors (antibodies)
- Specimen:
- Plasma in citrate tube, without epsilon - aminocaproic acid, aprotinin, heparin or other fibrinolysis inhibitors
- Reference range:
- Approximately 48 - 80 mg / dL, lower during first 5 days of life
- Functional assays:
- Add specific amount of excess plasmin to patient’s plasma, measure plasmin that is unbound to antiplasmin in patient’s serum by detecting color change spectrophotometrically
- Amount of unbound plasmin detected is inversely proportional to patient’s antiplasmin level
- Antigenic (immunologic) assay:
- Patient’s plasma in placed in the cylindrical well of an agarose gel containing antiplasmin antibody, which defuses into the well and forms an antigen - antibody complex and precipitin ring
- The size of the ring is proportional to the patient’s antiplasmin
- Acquired causes of decreased antiplasmin:
- Liver disease, thrombolytic therapy, DIC
Additional references
