Table 2.

Diagnostic procedures of quantitative fibrinogen disorders.

Diagnostic Procedures	Afibrinogenemia	Hypofibrinogenemia
Prothrombin time (PT)	extremely prolonged	prolonged/normal—depending on fibrinogen levels
Activated partial thromboplastin time (aPTT)	extremely prolonged	prolonged/normal—depending on fibrinogen levels
Thrombin time (TT)	extremely prolonged	prolonged/normal—depending on fibrinogen levels
Reptilase time (RT)	extremely prolonged	prolonged/normal—depending on fibrinogen levels
Fibrinogen activity (FBG: F (Clauss))	undetectable	proportional decrease
Fibrinogen antigen (FBG: Ag)	undetectable	proportional decrease
PT-derived fibrinogen assay	undetectable	decrease, proportional to fibrinogen levels
Genotype (FGA, FGB, FGG genes)
Global hemostasis tests (research laboratories)