Haemorrhagic Diathesis as the Result of Severe Deficiency of Plasma Thromboplastin Antecedent (PTA, Factor XI)

Abstract

The coagulation mechanism in a patient with multiple cerebral formation of haematomas after a relatively slight trauma gave rise to diagnostic difficulties. In the beginning a diagnosis of Hageman factor (factor-XII-) deficiency was made, but the results had to be reconsidered and the diagnosis changed into PTA(factor-XI-) deficiency. The authors communicate their difficulties in detail and explain their wrong interpretations which are attributable to the fact that both factors XI and XII are involved in the process of glass activation. Further it was pointed out that the activation of the factors VIII and IX is dependent on both PTA and HF. The narrow relationship of both factors is stressed.