PubMed HealthSearch

SEARCH · PubMed Health

Results for “Afibrinogenemia”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Coexistence of congenital afibrinogenemia and protein C deficiency in a patient.

A rare association of congenital afibrinogenemia and hereditary protein C deficiency is described in a 37-year-old female who suffered from ischemic necrosis in the left first toe. The diagnosis of afibrinogenemia was assessed by the absence of fibrinogen in clotting and immunological assays. The diagnosis of hereditary heterozygous type I protein C deficiency was based on the evidence of proportional decreases of activity and antigen of plasma protein C in the propositus, her mother, and two maternal aunts.

Adult

Platelet adhesiveness and aggregation in congenital afibrinogenemia. An investigation of three patients with post-transfusion, cross-correction studies between two of them.

Platelet adhesiveness and aggregation were studied in three patients with congenital afibrinogenemia. The results obtained may be summarized as follows: The retention of platelets to a glass-bead filter determined with the Salzman method was significantly decreased; it was normal after fibrinogen infusion. With a modification of the Hellem test the values obtained were slightly decreased. Adrenalin-induced aggregation was absent whereas ADP-and collagen-induced aggregation was near normal or slightly decreased. Thrombofax aggregation was absent in citrated plasma. The abnormalities of platelet aggregation were corrected after fibrinogen infusion or after addition in vitro of fibrinogen, hemofilia A plasma and PPP obtained from an afibrinogenemic patient after fibrinogen infusion. The abnormalities of platelet aggregation were corrected well by ADP, collagen and Thrombofax in heparinized blood, but only a slight correction of adrenalin-induced aggregation was noted. Thrombin aggregation proved to be normal with the higher concentrations, whereas it was defective with the lower ones. Ristocetin aggregation was normal in citrated plasma at the concentration of 1.5 mg per ml but it was absent at the lower concentration (1.0 mg per ml). Ristocetin aggregation was, on the other hand absent in heparinized blood regardless of the concentration. These findings are in agreement with the presence of a prolonged bleeding time in congenital afibrinogenemia and suggest that fibrinogen plays an important role in platelet aggregation and adhesiveness.

Adenosine Diphosphate

The effect of ionophore on platelet aggregation in von Willebrand's disease and in congenital afibrinogenemia. A comparison with ristocetin.

Platelet aggregation in citrated and heparinized plasma by ionophore A 23187 and Ristocetin was studied in normal subjects and in patients with von Willebrand's disease and congenital afibrinogenemia. Aggregation by ionophore was normal in all groups both in citrated and heparinized plasma. Aggregation by Ristocetin in citrated plasma was normal in congenital afibrinogenemia, in normal subjects and in types II and III of von Willebrand's disease. It was absent in classical von Willebrand's disease, type I. In heparinized plasma it was absent in all groups, except in some patients with von Willebrand's disease, type III. It is concluded that ionophore A 23187 behaves in a different way than Ristocetin and has no diagnostic implications.

Afibrinogenemia

Platelet fibrinogen: subcellular localization by means of immunofluorescent studies in normals and in congenital afibrinogenemia.

We have studied the site of fibrinogen localization in normal platelets and in the platelets of a patient with congenital afibrinogenemia (CA). The methods employed were: direct immunofluorescence technique (DIT) and indirect immunofluorescence technique (IIT). By means of the DIT normal platelets were shown to have a clear peripheral staining. Such staining disappeared after treatment with proteolytic enzymes and after specific blocking experiments. Such peripheral staining of platelets was absent in congenital afibrinogenemia even after fibrinogen infusion. By means of the IIT platelets were shown to have a considerable amount of fibrinogen. Such protein was demonstrated to represent an important part of platelet surface, since intact platelets were able to absorb completely a specific antifibrinogen antiserum.

Afibrinogenemia

Delayed-type hypersensitivity skin reactions in congenital afibrinogenemia lack fibrin deposition and induration.

Induration is a characteristic feature of delayed-type hypersensitivity skin reactions and is the usual measure of their intensity. The precise basis of induration has not been established, although activation of the clotting system with consequent fibrin deposition has been clearly implicated. In this study, two subjects with congenital afibrinogenemia, a genetic defect in fibrinogen synthesis, were skin tested with standard microbial antigens: streptokinase-streptodornase, monilia, mumps, and tuberculin purified protein derivative. One positive delayed reaction from each subject was biopsied at 40-48 h and compared with 23 biopsies of similar skin tests in normal volunteers. The eight skin tests in the afibrinogenic subjects lacked induration, although the erythema was similar in size (10-34 mm in diameter), intensity, and time-course to those in normals. Biopsies from the two strongest reactions from the afibrinogenemic subjects showed a typical perivascular mononuclear infiltrate. No more than traces of fibrin/fibrinogen were detected by immunofluorescence, in striking contrast to the abundant fibrin/fibrinogen deposition in 23 positive, indurated reactions in normal subjects. These findings indicate that fibrinogen itself is essential for the development of induration in delayed-type skin reactions in man. As judged by 1-mum sections and fluorescence, this is probably a result of the formation of an extravascular fibrin gel.

Adult

Platelet function by afibrinogenemia.

Platelet function was studied in two cases with congenital afibrinogenemia. In these two cases there was no aggregation by ADP, while, there was increased calcium-induced platelet aggregation and decreased platelet adhesiveness to glass. Platelet aggregation was corrected in vitro, by addition of fibrinogen. It can be concluded from the above findings that the fibrinogen is an important factor for platelet aggregation by ADP and for platelet adhesion to glass surfaces, while platelet aggregation by thrombin does not need fibrinogen. The increased calcium-induced aggregation can be explained by postulating that thrombin finds no substrate to act upon except the platelets.

Afibrinogenemia

[4 cases of congenital afibrinogenemia (author's transl)].

Report on 4 members of one family with afibrinogenemia. 2 of them died of cerebral hemorrhage at the age of 10. The 2 surviving children are 8 and 10 years old. Plasmafibrinogen was determined in 69 members of the family. Only in the parents of 2 patients was plasmafibrinogen found to be slinghtly reduced. But in other members of the family fibrinogen was low. In our cases, too, the ADP induced aggregation of thrombocytes in plasma obtained with citrate was weaker than normal.

Adenosine Diphosphate

Stimulation of fibrinogen synthesis by thrombin in rabbits with ancrod-induced afibrinogenemia.

The effect of intravenous infusions of thrombin on fibrinogen synthesis was evaluated in rabbits rendered afibrinogenemic by ancrod. Fibrinogen production and catabolism were measured simultaneously with 75Se-labeled selenomethionine (75SeM) and with 125I-labeled fibrinogen injected 5, 12, 18, or 26 h after ancrod. In normal rabbits the infusion of ancrod (2 U/kg body mass during 1 h) did not alter fibrinogen synthesis nor did it affect the rate of fibrinogen catabolism measured during a period of 5-120 h after ancrod administration. Normal rabbits that received purified bovine thrombin (100 U/kg body mass during 1 h) exhibited a twofold stimulation of fibrinogen synthesis as measured by the incorporation of 75SeM injected 5 h after thrombin. Rabbits made afibrinogenemic by infusion of ancrod 5 h before thrombin also showed a twofold increase in fibrinogen synthesis, as did animals that received ancrod immediately after thrombin. These experiments show that ancrod alone has no effect on fibrinogen production, and that thrombin stimulates fibrinogen synthesis in afibrinogenemic rabbits to the same extent as in controls.

Afibrinogenemia

The effect of heparin on platelet aggregation by common inductors and by ristocetin in congenital bleeding disorders due to factor VIII or fibrinogen defects.

Platelet aggregation by various inductors was studied in citrated and heparinized plasma of the following groups of subjects: Normal, hemophilia A, combined factor V and factor VIII deficiency, v. Willeprand's disease and congenital afibrinognemia. The results may be summarized as follows: A-platelet aggregation in citrated plasm 1) platelet aggregation by common inductors ADP, adrenalin and collagen was normal in all groups of subjects but for the patients with congential afibrinogenemia in whom adrenalin induced aggregation was absent or markedly refuced whereas ADP and collagen gave slightly reduced or near normal aggregation curves. 2) platelet aggregation by ristocetin was normal in all groups of subjects but for v. Willebrand's disease in which it was absent. B-platelet aggregation in heparized plasma. 1) platelet aggregation by common inductors resulted to be normal in all groups of subjects except in congenital afibrinogenemia. In this latter case the pattern was still mildly defective but here was an increased aggregation as compared to citrated plasma. These findings have been interpretemmon inductors. 2) platelet aggregation by ristocetin resulted to be absent in all groups of subjects investigated. The possible mechanism of action of the inhibitory effect exercised py heparin with regard to restocetin is discussed.

Adenosine Diphosphate

Inherited bleeding syndromes in Jordan.

This paper presents data on the occurrence and pattern of inherited bleeding syndromes (IBS) in Jordan, a hitherto unexplored problem. In 1978, during the first 12 months of a prospective study at a major medical center, 91 patients from 51 families were diagnosed as having IBS. All patients were referred because of moderate-to-severe bleeding diatheses; they included 52 hemophiliacs, 27 patients with von Willebrand's disease, 4 with hemophilia B (IX-deficit), 2 with afibrinogenemia, 1 with prothrombin deficiency, and 4 were thought to have platelet dysfunction. The clinical and laboratory features of the patients observed in Jordan do not seem to be significantly different from those of patients in Western Europe or North America.

Adolescent

Reaction of blood with artificial surfaces of hemodialyzers. Studies of human blood with platelet defects or coagulation factor deficiencies.

Heparinized human blood was exposed to the dialysis membranes of commercially available pediatric size hemodialyzers in an in vitro flow circuit. Bloods from normal subjects and from patients with various blood coagulation and platelet function deficiencies were tested in this model system. In most cases, there was a heavy linear deposit of leukocytes on the dialysis membrane overlying support structures. In other areas, the cellular deposit was less uniform and consisted of single platelets, platelet aggregates, leukocytes, and occasional fibrocellular microthrombi. The number of adherent platelets was smaller in tests with blood from patients with congenital afibrinogenemia, factor XII deficiency, severe von Willebrand's disease, and thrombasthenia then in tests with blood from normal subjects or hemophilic patients. Hence, fibrinogen, factor XII, the von Willebrand factor, and a normal platelet plasma membrane appear necessary for adhesion of platelets to dialysis membranes.

Afibrinogenemia

Inherited bleeding syndromes in Iraq.

This paper presents data on the occurence and pattern of inherited bleeding syndromes (IBS) in Iraq, a hitherto unexplored problem. During the first fourteen months of a prospective on-going study at a major university center, 116 patients from 62 families were diagnosed as having IBS. All patients were referred because of moderate to severe bleeding diatheses. They included 62 haemophiliacs 32 patients with von Willebrand's disease (VWD), 9 with Christmas disease (CD), 6 with afibrinogenemia, 1 with prothrombin deficiency, and 6 were thought to have platelet dysfunction. 32 other bleeders (16 hemophiliacs, 14 VWD, and 2 CD) were also recognized among the pedigrees studied but were not available for full investigations. The clinical and laboratory features of the patients observed in Iraq do not seem to be significantly different from those of patients in Western Europe or North America. Although the absolute incidence and relative distribution of these disorders in the entire population cannot yet be determined, the rate of occurence per segment population is likely to be high, most likely due to the high rate of consanguinity and large number of births per family, phenomena still prevalent in this country.

Adolescent