Haemostatical and rheological aspects of dysfibrinogenemia.

Congenital dysfibrinogenemia is based on different alterations in the structure of the fibrinogen molecule leading to a variety of disturbances in the clotting process. Clinical manifestations of the disorder are showing a wide range from asymptomatic states to mild bleeding diathesis as well as thrombotic complications. In this study two of the 14 patients with dysfibrinogenemia showed a history of mild bleeding while the others showed no clinical symptoms. As fibrinogen is also an important factor of the blood fluidity not only haemostatic but also rheological parameters were measured. Included in the study were 14 patients with ascertained dysfibrinogenemia in comparison to 11 non-affected relatives and a control group of 297 apparently healthy subjects. Plasma viscosity (p < 0.0001) and erythrocyte aggregation index (p < 0.00001) were significantly higher in the patients than in their healthy relatives and the control group. A pathologically increased erythrocyte aggregation was found in 10 of the 14 patients but only in 1 of the 10 relatives. The dysfunction of the fibrinogen molecule thus influences the aggregation process of the red blood cells to a greater extent than normal fibrinogen. Moreover, there seems to be a stronger influence of the dysfunctional fibrinogen molecule on the aggregation process than on plasma viscosity. To date the question if the enhanced erythrocyte aggregation in dysfibrinogenemic patients may be of any diagnostic interest and if there are significant differences between patients with bleeding diathesis and thrombophilia cannot be answered and remains to be cleared in further investigations.