[Prekallikrein (Fletcher Factor) Deficiency and Prolongation of APTT Reaction]

Prekallikrein (Fletcher factor) is a protein of the contact phase of the blood coagulation system. A deficiency is a very rare event. The clinical meaning is still unknown.

In a 24-year-old patient of Croatian nationality, who has never suffered from any kind of proneness to hemorrhage, a considerable prolongation of activated partial thromboplastin time (APTT) was diagnosed preoperatively. The prothrombin time (PT) was normal. The patient had to be subjected to horseshoe-kidney surgery. CLOTTING TESTS: A very seldom Fletcher factor (prekallikrein) deficiency type II was detected. The activity was < 1%, but the prekallikrein concentration was normal, comparable to that in normal plasma.

Complications were neither noticed during renal surgery nor postoperatively. The patient did not show clinical symptoms. This fact corroborates reports about similar cases published earlier.

Nevertheless, attention has to be paid to these exceptionally rare symptoms, as in some publications, thromboembolic or even bleeding complications were reported.