- Last Update On : 2013-01-13
Factor XIII, fibrin stabilizing factor, is necessary for crosslinking molecules of fibrin to form a stable clot. Clots formed in the absence of activated Factor XIII lack stability and are easily lysed by proteolytic enzymes.
Normal clots do not dissolve in less than 24 hours. A level of less than 1‑2% Factor XIII will produce a clot which dissolves in concentrated urea or weak acid. A positive test (dissolution of the clot in < 24 hours) indicates severe Factor XIII deficiency (the homozygous state). Clinically, patients with homozygous Factor XIII deficiency present with soft tissue bleeding, postoperative bleeding, umbilical cord hemorrhage in neonates, and delayed wound healing.
Specimen requirement is one light blue top (sodium citrate) tube of blood.