ristocetin and Blood-Coagulation-Disorders

Topics: Adult; Antigens; Blood Coagulation Disorders; Blood Transfusion; Child; Child, Preschool; Factor V Deficiency; Factor VIII; Factor XI Deficiency; Female; Hemophilia A; Hemophilia B; Humans; Male; Pedigree; Ristocetin; Syndrome

Topics: Adenosine Diphosphate; Adenosine Triphosphate; Anemia, Megaloblastic; Anti-Inflammatory Agents; Blood Coagulation Disorders; Blood Coagulation Tests; Blood Platelet Disorders; Blood Platelets; Carbenicillin; Collagen; Epinephrine; Hemorrhage; Humans; Isoantibodies; Leukemia; Myeloproliferative Disorders; Platelet Aggregation; Postoperative Complications; Purpura, Thrombocytopenic; Ristocetin; Stress, Psychological; Uremia; von Willebrand Diseases

We report an unusual case of severe abdominal arterial thrombosis in a young woman using oral desmopressin. Only a few cases with cerebrovascular accidents and coronary syndromes have been described so far, which could be attributed to intravenous administration of desmopressin. Because extensive diagnostic and laboratory investigations for (un)common coagulation disorders could not identify an alternative explanation associated with arterial thrombosis, we hypothesise that desmopressin in an oral dose of at least 200 ug once daily must have been sufficient to cause this dramatic vascular complication. Supportive of our hypothesis, we found remarkably high levels of factor VIII activity, Von Willebrand factor (vWF) antigen and vWF ristocetin cofactor activity (268%, 740%, 590% respectively). To the best of the authors' knowledge, this is the first report suggesting a relationship between oral desmopressin use and life-threatening abdominal arterial thrombosis.

Topics: Abdominal Pain; Adult; Blood Coagulation Disorders; Cerebrovascular Disorders; Deamino Arginine Vasopressin; Echocardiography; Factor VIII; Female; Hemostatics; Humans; Ristocetin; Thrombosis; Tomography, X-Ray Computed; von Willebrand Factor

The Impact-R [Cone and plate(let) analyzer (CPA)] is useful to assess platelet adhesion in different diseases and to monitor antiplatelet therapy. The purpose of the present study was to adapt this system to test agonist-induced platelet aggregation. Blood samples were tested by light transmission platelet aggregometry (LTA), Impact-R regular test and Impact-R agonist-response test. In the latter, samples were pre-incubated for 1 min with an agonist leading to platelet activation, micro-aggregates formation and reduced adhesion. Impact-R regular test of ten healthy volunteers demonstrated platelet adhesion (surface coverage, SC) of 11.2 +/- 2.6% while LTA induced by ADP, ristocetin, epinephrine, collagen and arachidonic acid (AA) yielded maximal aggregation (81% to 93%). In the Impact-R agonist-response test, SC was reduced to 2.2 +/- 1.0%, 1.2 +/- 0.9%, 2.3 +/- 1.0%, 2.2 +/- 0.8% and 2.4 +/- 0.4%, respectively. Prostaglandin E(1) treatment weakened SC reduction in response to ADP and epinephrine (SC of 8.8 +/- 1.8% and 9.5 +/- 2.0%, respectively). Inhibition of P2Y(12) receptor with 2MeSAMP resulted in a dose-dependent decrease in maximal aggregation in the ADP-induced test, which inversely correlated to SC in the Impact-R ADP-response test. The Impact-R agonist-response tests detected aggregation defects in patients with storage pool disease, severe von Willebrand disease and epinephrine response deficiency, and may be useful to assess the effect of different agonists on platelet aggregation.

Topics: Adenosine Diphosphate; Adult; Alprostadil; Arachidonic Acid; Blood Coagulation Disorders; Collagen; Epinephrine; Female; Humans; Male; Middle Aged; Platelet Activation; Platelet Aggregation; Platelet Function Tests; Ristocetin; Young Adult

Four hundred and ninety seven patients were referred to our center for platelet aggregation studies because of spontaneous mucocutaneous bleeds. All these patients had normal complete blood count, platelet count and peripheral smears except in ten patients of Bernard Soulier Syndrome where platelet count was marginally reduced in the presence of giant platelets. Two hundred and eighty patients were found to have normal platelet aggregation to ADP, collagen, ristocetin and arachidonic acid. Out of the remaining 217 patients, 62 patients were diagnosed to have Glanzmanns thrombasthenia, 10 Bernard Soulier Syndrome, 6 storage pool deficiencies, 7 cyclooxygenase deficiencies and 72 von Willebrand disease. In all the patients with GT and BSS, diagnosis was confirmed with flow cytometry using multiple monoclonal antibodies to GPIIb-IIIa and GPIb-IX. There were sixty patients where initial platelet aggregation studies showed reduced (<30%) aggregation to either ADP, collagen, ristocetin or arachidonic acid in its various combination, however in 12 such patients (20%) the platelet aggregation studies were normal on repetition. All our platelet aggregation studies were done only after assuring that the patient is not taking any medicine for at least 7-10 days which may affect the platelet function tests. The present study shows that single atypically abnormal platelet aggregation studies should always be repeated. Finally in 48/217 patients (22%) some aggregation abnormality to one or more of the agonists persisted, although we could not categorize these patients into any clear-cut platelet disorder. None of these 48 patients platelet associated immunoglobulin was increased by flow cytometry. It is possible that large number of patients from that disorder will finally prove to be some form of platelet secretory defect. In north India similar group of defect in a large number of patients have been reported as isolated PF3 abnormality or thrombasthenic thrombopathy.

Topics: Adenosine Diphosphate; Arachidonic Acid; Bernard-Soulier Syndrome; Blood Coagulation Disorders; Blood Platelets; Collagen; Flow Cytometry; Humans; Platelet Aggregation; Prostaglandin-Endoperoxide Synthases; Reference Values; Ristocetin; Thrombasthenia; von Willebrand Diseases

Uremia causes a bleeding tendency associated with platelet dysfunction, and previous studies have shown abnormalities of platelet glycoprotein (GP) Ib or GPIIb/IIIa and a tendency for platelet activation in uremia. The present study compared the abnormalities of platelet function in uremia with (n = 1) or without (n = 18) associated Glanzmann's thrombasthenia. There was a significant difference between ristocetin-induced agglutination of platelets from the uremic patients without Glanzmann's thrombasthenia and platelets from healthy controls (n = 15). In addition, a reduction of GPIb expression by uremic platelets along with normal GPIIb/IIIa expression was confirmed using flow cytometry. Many coagulation markers were increased in the uremic patient with Glanzmann's thrombasthenia, suggesting that the coagulation was enhanced and the platelets were prone to activation. However, the thrombasthenic platelets actually showed little increase in the binding of a monoclonal anti-CD63 antibody directed against lysosomal integral membrane protein (which is expressed after platelet activation), while uremic platelets showed a marked increase. In addition, the expression of GPIb by thrombasthenic platelets was normal, while that of GPIIb/IIIa was markedly decreased. Our results suggest that thrombasthenic platelets are resistant to activation and to the degradation of GPIb under uremic condition and that this difference from 'ordinary' uremic platelets be related to the difference in GPIIb/IIIa.

Topics: Adult; Blood Coagulation; Blood Coagulation Disorders; Blood Platelets; Female; Fibrinolysis; Flow Cytometry; Fluorescent Antibody Technique; Humans; Platelet Aggregation; Platelet Membrane Glycoproteins; Renal Dialysis; Ristocetin; Thrombasthenia; Uremia

We examined, platelet adhesive function in vivo by comparing the platelet retention rate (PRR) with other laboratory tests. In 71 patients, PRR did not correlate with bleeding time (BT), ristocetin-induced platelet agglutination (RIPA), vWF:AG, vWF:RCo, FVIII:C, fibrinogen, platelets counts or platelet aggregation tests. Among them, the coincidence rate of PRR with BT seems relatively better than that of other tests. In patients with Bernard-Soulier syndrome (BSS), PRR, RIPA and high shear-induced platelet aggregation (SIPA), measured using a cone-plate type instrument, were decreased, while platelet adhesion in a static system and SIPA at a low shear rate were normal. In patients with Glanzmann's thrombasthenia (TA), PRR and SIPA were decreased at both high and low shear rates, while RIPA and platelet adhesion were normal in a static system. In patients with deficient glycoprotein Ia/IIa complex which is one of the putative receptors for collagen, platelet adhesion in a static system is markedly decreased. In patients with von Willebrand disease, the pattern of platelet adhesion tests was similar to that of BSS patients, while in patients with afibrinogenemia, it was similar to that of TA patients except for SIPA at a high shear rate. The various experiments using monoclonal antibodies support these abnormalities. These findings, suggest that PRR is a suitable screening test, but further rapid and easy tests will be necessary to diagnose the defects of platelet adhesion at various shear rates.

Topics: Bleeding Time; Blood Coagulation Disorders; Factor VIII; Humans; Platelet Adhesiveness; Platelet Aggregation; Platelet Function Tests; Platelet Membrane Glycoproteins; Ristocetin; von Willebrand Factor

We examined an inhibitor to factor VIII in non-haemophilic patient who had been developed widely spread ecchymosis and intramuscular bleeding. He had no previous personal or family history of abnormal bleeding tendency. His laboratory data was all normal except examination for blood coagulation. Coagulation studies showed prolonged activated partial thromboplastin time (48 sec) and decreased factor VIII activity (8%). The activity of the inhibitor to factor VIII was demonstrated to be 4.0 Bethesda unit. By the studies of dilution and time response curve, this inhibitor was found to inhibit up to 90% of factor VIII activity but not 100%. This inhibitor was shown to be IgG by protein-A affinity chromatography. In addition, bleeding time was prolonged in the patient. The value of von Willebrand factor antigen was 200%, but that of Ristocetin cofactor was 93%. Since the gel filtration analysis indicated that this inhibitor also suppressed Ristocetin cofactor activity, the relatively low value of Ristocetin cofactor might occur through the action of the inhibitor. These data suggest that patient's inhibitor react to factor VIII high molecular subunit.

Topics: Blood Coagulation Disorders; Factor VIII; Humans; Male; Middle Aged; Ristocetin; von Willebrand Factor

Thirty-four cases of inherited bleeding disorders are reported. All are Saudi patients from the Eastern Province of Saudi Arabia. There were 15 haemophiliacs, 1 factor VII deficiency, 1 factor X deficiency, 12 Glanzmann's thrombasthenia, and 5 unidentified platelet function disorders. Consanguinity was common among the families of these patients. Different age groups were affected and the severity of bleeding varied in the different conditions reported.

Topics: Adenosine Diphosphate; Adolescent; Adult; Arachidonic Acid; Arachidonic Acids; Blood Coagulation Disorders; Blood Platelet Disorders; Child; Child, Preschool; Collagen; Consanguinity; Epinephrine; Female; Humans; Infant; Male; Platelet Aggregation; Ristocetin; Saudi Arabia

Topics: Adult; Blood Coagulation Disorders; Child; Collagen; Estrogens, Conjugated (USP); Female; Humans; Kidney Transplantation; Male; Platelet Aggregation; Ristocetin

Topics: Adolescent; Adult; Blood Coagulation Disorders; Child; Female; Heterozygote; Humans; Male; Middle Aged; Platelet Aggregation; Ristocetin

A method is described for measuring platelet aggregation by serial counting of platelets in whole blood, using the Ortho ELT 8/ds blood cell counter. The method is simple, rapid, reproducible and more sensitive to low concentrations of ADP and other agonists than conventional aggregometry on platelet-rich plasma. It can be used as a diagnostic test for disorders of platelet function using as little as 2 ml of whole blood: results in thrombasthenia, Hermansky-Pudlak and Bernard Soulier syndromes and von Willebrand's disease are shown.

Topics: Adenosine Diphosphate; Blood Coagulation Disorders; Epinephrine; Humans; Platelet Aggregation; Platelet Count; Ristocetin

Platelet aggregation to common inductors and to Ristocetin, Thrombofax and Ionophore is normal in congenital factor X deficiency and in factor X Friuli coagulation disorders. Washed normal platelets resuspended in the patient's plasma and in adsorbed normal plasma showed a normal aggregation. On the contrary, normal platelets resuspended in normal serum failed to aggregate. These studies indicate that factor X plays no role in normal platelet aggregation.

Topics: Adenosine Diphosphate; Blood Coagulation Disorders; Calcimycin; Collagen; Epinephrine; Factor X Deficiency; Humans; Hypoprothrombinemias; Platelet Adhesiveness; Platelet Aggregation; Ristocetin; Thromboplastin

A case of Glanzmann's thrombasthenia is documented in a Melanesian child, and the diagnosis and treatment of this disorder are discussed. This is the third inherited bleeding disorder to be reported in Papua New Guinea, haemophilia A (Factor VIII deficiency) and Factor XIII deficiency having been described previously.

Topics: Blood Coagulation Disorders; Blood Coagulation Tests; Blood Platelets; Child, Preschool; Epistaxis; Female; Humans; Male; New Guinea; Platelet Aggregation; Ristocetin

Treatment of von Willebrand disease with two plasma antihemophilic factor (AHF) concentrates, cryoprecipitate and glycine-precipitated AHF, was compared. Both concentrates were equally effective in immediately raising the plasma levels of factor VIII, the factor VIII-related antigen, and the ristocetin-related von Willebrand factor (vWF) and in stimulating a secondary rise in plasma factor VIII. Given either concentrate, the vWF activity, the antigen, and factor VIII levels were normalized in a patient with von Willebrand disease. However, correction of the prolonged bleeding time and control of bleeding occurred only with the cryoprecipitate. The bleeding-time corrective factor and the ristocetin-related vWF or platelet-aggregating factor are dissociable, distinct activites.

Topics: Antigens; Blood Coagulation Disorders; Blood Coagulation Tests; Chemical Precipitation; Factor VIII; Glycine; Hemostasis; Humans; Male; Middle Aged; Ristocetin; von Willebrand Diseases

Normal subjects, patients with various bleeding disorders, and patients with von Willebrand's disease were studied. All patients with von Willebrand's disease had decreased levels of ristocetin-Willebrand factor (range, 0 to 41%) as compared with all other subjects (range, 79 to 202%). Ristocetin-induced platelet aggregation of platelet-rich plasma was abnormal in all patients with von Willebrand's disease tested, and it was possible to correct this abnormal response by addition of normal platelet-poor plasma. Abnormal ristocetin-induced platelet aggregation was seen in patients with intrinsic platelet disorders or, on some occasions, in normal patients who had ingested aspirin. Ristocetin-induced platelet aggregation is not diagnostic, but it may be useful as a simple screening test for patients with possible von Willebrand's disease. In conjunction with other tests, the assay for ristocetin-Willebrand factor will be useful in diagnosis and evaluation of these patients.

Topics: Anticoagulants; Antigens; Blood Coagulation Disorders; Blood Coagulation Factors; Blood Platelets; Factor VIII; Humans; Platelet Adhesiveness; Platelet Aggregation; Ristocetin; von Willebrand Diseases

Topics: Adolescent; Adult; Antigens; Blood Coagulation Disorders; Child; Child, Preschool; Factor VIII; Female; Humans; Male; Middle Aged; Platelet Aggregation; Ristocetin; Thrombocytopenia; von Willebrand Diseases

C-PRP clotted by reptilase does not retract due to the lack of activation of platelets. In order to support retraction, the platelets must undergo membrane changes resulting in contractile system activation. Only in the presence of aggregating agents capable of eliciting these membrane changes in vitro (e.g. ADP, adrenaline and collagen but not bovine fibrinogen or ristocetin), strong reptilase clot retraction (RCR) occurs. During RCR an aggregating activity, platelet factor 4, and retraction stimulating factor (RSF) were released, but acid phosphatase was not available. Not only inhibitors of platelet adhesion-aggregation reaction (PAAR) but also specific blockers of release are capable of inhibiting RCR. In coagulation disorders RCR was normal in most cases, but in thrombopathies different abnormalities of RCR were found. The RCR defect may be associated not only with a defect in the initial stages of PAAR, but in some instances also with a specific defect in release reaction. Besides inducer--"activated" platelets and their adhesion to polymerizing fibrin, the presence of divalent cations and free thrombocytar--SH groups is necessary for the retraction of reptilase clots.

Topics: Adenosine Diphosphate; Batroxobin; Blood Coagulation Disorders; Blood Platelets; Cations, Divalent; Clot Retraction; Collagen; Epinephrine; Fibrinogen; Humans; Peptide Hydrolases; Platelet Adhesiveness; Platelet Aggregation; Ristocetin; Sulfhydryl Compounds

Ellagic acid solutions, regardless of the concentration, failed to alter platelet aggregation induced by ADP, Adrenalin, Collagen, Thrombofax and Ristocetin in normal and in factor XII deficient plasma. A moderate inhibition was noted after addition of ADP both in normal and in factor XII deficient plasma but this was present also in the control systems and was therefore due to the buffer-dextrose solution and not to ellagic acid. These data indicate that Hageman factor plays on role in platelet aggregation.

Topics: Adenosine Diphosphate; Benzopyrans; Blood Coagulation Disorders; Collagen; Ellagic Acid; Epinephrine; Factor XII Deficiency; Female; Humans; Male; Platelet Adhesiveness; Ristocetin

Topics: Animals; Antigens; Blood Coagulation Disorders; Blood Platelets; Factor VIII; Humans; Immunoelectrophoresis; Purpura, Thrombocytopenic; Rabbits; Ristocetin; Syndrome; von Willebrand Diseases

Topics: Adenosine Diphosphate; Aged; Blood Cell Count; Blood Coagulation Disorders; Blood Coagulation Tests; Blood Platelets; Blood Proteins; Collagen; Electrophoresis; Female; Fibrinogen; Gastrointestinal Hemorrhage; Humans; Male; Microscopy, Electron; Middle Aged; Platelet Aggregation; Ristocetin; Sialic Acids; Stimulation, Chemical; Thrombocytopenia