Which statement about fibrinogen degradation products (FDP) testing is true?

• A. It detects only cross-linked fibrin
• B. It detects any fibrin degradation products, not specific to cross-linked products
• C. It measures platelet aggregation
• D. It indicates factor VIII activity

Answer: (B)

Fibrinogen degradation product testing looks for the fragments produced when plasmin breaks down fibrin and fibrinogen. Because plasmin acts on both fibrinogen and fibrin, the assay detects a broad range of degradation products, not just those from crosslinked fibrin. That means it’s not specific to cross-linked fibrin, which is why the correct choice states that FDP testing detects any fibrin degradation products, not only cross-linked ones. This differs from tests like D-dimer, which specifically reflect breakdown of crosslinked fibrin. FDP testing has no relation to platelet aggregation or to factor VIII activity, so those statements aren’t true.