Congenital abnormal fibrinogens.

Congenital and hereditary abnormal fibrinogen is the most common of the inherited disorders of fibrinogen. There is no uniform clinical pattern which characterizes the disease and the diagnosis is evoked on the results of laboratory tests which show an abnormal conversion of fibrinogen to fibrin. This abnormality should be confirmed on the purified defective fibrinogen. Characterization of the abnormality includes physical, immunological, functional and structural analyses. Studies related to fibrinogen behavior upon plasmin digestion and those related to polymerization also provide useful information. Recognition of the specific nature of the molecular defect is dependent on molecular analysis. A single distinctive amino acid substitution is currently recognized for Fibrinogen Detroit, Lille and München.