Fibrinogen Concentration

Purpose

• The Thrombin Time is used to screen for reduction in fibrinogen concentration.
• The Fibrinogen Titer Test can also be used. (Discussed below.)

Methods

• Thrombin Time (Click to go to Thrombin Time section)
• Fibrinogen Titer Test

1. Thrombin is added to serial dilutions of plasma in buffered saline.
2. The dilutions in which clot formation is visible are noted.

Interpretation

• Clot should normally be visible at a dilution of 1:64, and is usually seen at 1:128.
• Visible clot in these dilution rules out a clinically significant quantitative abnormality in fibrinogen and estimates the concentration to be greater than 100 mg/dL.