Abnormal Prothrombin Consumption (Pc) In Bernard Soulier-Syndrome (BSS)

1981 ◽  
Author(s):  
J Pizzuto ◽  
M P Reyna ◽  
A González-Angulo ◽  
M R Morales ◽  
S Dorantes

The abnormal PC in BSS is a defect that has not been extensively studied to date. For this reason 4 patients with BSS who had normal platelet aggregation tests (except with bovine fibrinogen and with Ristocetin), but abnormal bleeding times and PC on different occasions, during which they showed variable thrombocytopenia, were studied. The PC was normal in only one case and in only one occasion, which was coincidental with a circulating platelet count that also approximated normal.The abnormal PC in the 4 cases was corrected when platelet substitute, or washed platelets from normal subjects or from patients with BSS were added. These same platelets also corrected the abnormal PC in cases of ITP or aplastic anemia, and shortened the recalcification time of platelet-poor plasmas from normal subjects and patients with specific plasma deficiencies (Factors V, VIII and XI).The above suggests that the abnormal PC in some cases of BSS may be due to the thrombocytopenia rather than to a defect in the procoagulant activity of the platelets in this syndrome.

1987 ◽  
Vol 57 (02) ◽  
pp. 222-225 ◽  
Author(s):  
A H Soberay ◽  
M C Herzberg ◽  
J D Rudney ◽  
H K Nieuwenhuis ◽  
J J Sixma ◽  
...  

SummaryThe ability of endocarditis and dental strains of Streptococcus sanguis to induce platelet aggregation in plasma (PRP) from normal subjects were examined and compared to responses of PRP with known platelet membrane glycoprotein (GP) and response defects. S. sanguis strains differed in their ability to induce normal PRPs to aggregate. Strains that induced PRP aggregation in more than 60% of donors were significantly faster agonists (mean lag times to onset of aggregation less than 6 min) than those strains inducing response in PRPs of fewer than 60% of donors.Platelets from patients with Bernard-Soulier syndrome aggregated in response to strains of S. sanguis. In contrast, platelets from patients with Glanzmann’s thrombasthenia and from a patient with a specific defect in response to collagen were unresponsive to S. sanguis. These observations show that GPIb and V are not essential, but GPIIb-IIIa and GPIa are important in the platelet response mechanism to S. sanguis. Indeed, the data suggests that the platelet interaction mechanisms of S. sanguis and collagen may be similar.


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3960-3960
Author(s):  
Arash Rezazadeh ◽  
Sandra C. Hollensead ◽  
Damian A. Laber ◽  
Goetz H. Kloecker

Abstract A 42 year-old man with Osteogenesis Imperfecta (OI) had three episodes of spontaneous Subdural Hematoma (SH) after binge drinking. There is no remote history of abnormal bleeding or easy bruising despite multiple fractures. Medications included Aspirin (ASA). The first and second SH occurred within the preceding year and were treated conservatively. The third SH occurred while on ASA and drinking more than 500cc liquor/day. The Platelet Function Assay (PFA-100) was significantly abnormal (see table). After platelet transfusions the SH was surgically evacuated without complications. An MRA of the head showed no vascular abnormality. CBC, serum chemistries, PT, PTT, factor VIII and von Willebrand factor were normal. The patient stopped taking ASA, but continued to drink. The PFA-100, although abnormal, had improved. After a month-long alcohol abstinence his PFA-100 normalized. He has been without SH ever since. However the platelet aggregation study still shows a lack of second wave response to ADP. EVENT ASA ETOH Collagen/Epi Collagen/ADP Platelet Count SH3 (+) (+) >300 112 266 Plt transfusion n/a n/a 122 51 347 Follow up (−) (+) 219 108 231 Follow up (−) (−) 117 80 276 Reference Range 118–162 Seconds 59–103 Seconds 140–370 Discussion: Both OI and ETOH are known factors of causing intrinsic platelet defect. The Framingham Offspring Study showed that alcohol consumption is inversely associated with both platelet activation and aggregation, particularly in men. ETOH is capable of inhibiting collagen induced platelet aggregation, secretion, arachidonate mobilization, and TXA2 formation. Also it has been suggested that intracellular Ca2+ homeostasis and aggregation in platelets are impaired by ethanol through the generation of H2O2 and oxidation of sulphydryl groups. OI causes vascular fragility and intrinsic platelet defect. In one study the most frequent abnormalities were increased capillary fragility (35%), decreased platelet retention (33%) and reduced factor VIII R:Ag (23%). Reduced ristocetin cofactor, deficient platelet aggregation induced by collagen and prolonged bleeding time were less common findings. The combination of vascular, platelet related and plasmatic defects may reflect that OI is a heterogeneous group of disorders with common clinical expression. Conclusion: Patients with OI are at risk for intracranial bleeding due to vascular fragility and intrinsic platelet defect. Our patient had a normal PFA-100, off ASA and ETOH. The platelet aggregation study -a more sensitive test- was able to detect a platelet secretion defect in our patient. The abnormal platelet aggregation study was likely due to his OI, which never caused abnormal bleeding by itself. The additional affect of ASA and ETOH on his platelets led to recurrent episodes of SH. Many OI patients are on NSAID/ASA due to chronic bone pain. Special attention should be paid to alcohol abuse in this group of patients. Normal platelet counts and coagulation tests may not be sufficient to evaluate the risk of bleeding. We suggest performing a PFA-100 or a platelet aggregation study, when platelet dysfunction is suspected.


1980 ◽  
Vol 43 (02) ◽  
pp. 154-157 ◽  
Author(s):  
Bernard S Kaplan ◽  
Jack S C Fong

SummaryPlatelet aggregation was studied in three patients during the course of the hemolytic-uremic syndrome (HUS) when the platelet count was below 100,000/mm3 and after the platelet count had normalized. Platelet aggregation was examined in response to epinephrine, adenosine diphosphate (ADP) and collagen. Aggregation did not occur in response to epinephrine when the patients were thrombocytopenic but normal tracings were obtained when the platelet counts had returned to normal. In contrast, platelet-rich plasma from normal subjects diluted with platelet-poor plasma from patients to comparable platelet counts, showed normal aggregation responses. This study demonstrates that platelet aggregation is reduced in the early phase of the HUS.


1979 ◽  
Author(s):  
W. Hanna ◽  
C. McCarroll ◽  
J. Chen ◽  
T. McDonald ◽  
D. Lin ◽  
...  

This family carries multihematological inherited disorders; namely, von Wille-brand’s, vascular telangiectasia and hemoglobinopathy. Family members were studied by quantifying the following: Factor VIII pro-coagulant activity, Factor VIII related antigen, Factor VIII inhibitors, platelet adhesion, platelet aggregation (with ristocetin, collagen and ADP), bleeding time, platelet count, partial thromboplastin time, prothrombin time, hemoglobin electrophoresis, hemoglobin finger-printing, sickling preparation and the presence of telangiectasia.The affected members of this family with von Willebrand’s express their disease in a variable tendency to bleeding from almost clinically asymptomatic cases to cases with severe bleeding tendency.One member of this family had to have a hysterectomy at the age of 20 to control the abnormal uterine bleeding after conservative treatment failed. All affected members with von Willebrand’s disease had a normal platelet count, prolonged bleeding time, decreased Factor VIII pro-coagulant activity and related antigen, negative aggregation using the ristocetin co-factor for von Willebrand’s, defective platelet adhesiveness to glass beads, and normal platelet aggregation to collagen and ADP. Some members have vascular telangiectasia in the mucous membranes. An incidental finding was the presence of an abnormal hemoglobin S in some family members.Supported in part by the Cumberland Chapter of the National Hemophilia Foundation.


1970 ◽  
Vol 8 (2) ◽  
pp. 57-59
Author(s):  
Momotaj Begum ◽  
Ma Hai ◽  
ASM Lokman Hossain Chowdhury ◽  
Noorjahan Begum

This was a prospective study. The study was done from July 1997 to June 98. All the cases were selected from the outdoor patients of National Institute of Cardiovascular Diseases (NICVD), Controls were selected from healthy volunteers. The plasma fibrinogen level, platelet aggregation and platelet count were studied on a total number of 35 subjects with age ranged from 40-60 years of both sexes. Of these 20 were normal healthy subjects and 15 were patients with stable angina. Plasma fibrinogen level were normal as like as healthy subjects. Platelet aggreagations were increased in some cases but others show normal findings. The platelet count were slightly decreased but it was within normal range. Form this study it may be observed that normal plasma fibrinogen level and increased platelet aggregation with normal platelet count may occur in patients with stable angina. The increased platelet aggregation indicate hypercoagulable states which may aggravate the condition of patients with stable angina and this is the risk factor for the further development of severe ischemia of the heart. So, the routine investigation of plasma fibrinogen level, platelet aggregation and platelet count may be helpful to utilize them as background information both for therapeutic and preventive measures in patients with stable angina.     DOI = 10.3329/jom.v8i2.1408 J MEDICINE 2007; 8 : 57-59


1969 ◽  
Vol 22 (03) ◽  
pp. 482-495 ◽  
Author(s):  
L Grotto ◽  
Z Jerushalmy ◽  
A de Vries

SummaryPurified Vipera palestinae hemorrhagin (VPH) impairs thrombin formation, fibrinogen clottability, FSF activity, platelet clot retracting activity, ADP- and connective tissue-induced platelet aggregation and connective tissue - induced platelet ADP release. The effects of VPH became manifest or increased in intensity on incubation with the respective substrates prior to measurement of their activities. Inactivation of the VPH protease by DFP resulted in complete abolishment of the first four and partial inhibition of the last two of the above VPH activities.Administration of VPH to guinea pigs caused widespread hemorrhages, associated with moderate hypofibrinogenemia but normal platelet count, clotting time and clot retraction. DFP-treated VPH caused hemorrhage without hypofibrinogenemia.


2001 ◽  
Vol 86 (10) ◽  
pp. 1065-1069 ◽  
Author(s):  
Donna Pedicord ◽  
Dietmar Seiffert ◽  
G.A. Jamieson ◽  
Nicholas Greco ◽  
Ira Dicker

SummaryPlatelets activated by -thrombin express surface procoagulant activity (PCA) that accelerates the conversion of prothrombin to α-thrombin. Following activation with 10 nM α-thrombin, the PCA of normal platelets was approximately five-fold higher than that of Bernard-Soulier platelets (lacking GPIb). Normal platelet PCA was inhibited ~50 % by activation in the presence of the anti-GPIb MoAbs LJIb10 or TM60. Moreover, normal platelet PCA was completely abrogated in the presence of a combination of both LJIb10 and c7E3, a MoAb directed against αIIbβ3 (GPIIb/IIIa). In contrast, PCA expressed by Bernard Soulier or Glanzmann platelets was not inhibited by either LJIb10 or c7E3 MoAb. The platelet activating peptide SFLLRN at 10 μM, a concentration which fully activates platelet aggregation and Ca2+ mobilization, generated PCA activity one fifth of that generated by α-thrombin at 10 nM but anti-PAR1 antibodies did not affect thrombin-induced PCA expression. These results demonstrate that GPIb mediates, at least in part, the thrombin-induced activation of platelets that leads to PCA, and that αIIbβ3 is also involved in PCA generation, but these results do not support a major role for PAR1 in this activation.


2021 ◽  
Vol 156 (Supplement_1) ◽  
pp. S101-S101
Author(s):  
C A Cox ◽  
H Hastings

Abstract Introduction/Objective Acquired Glanzmann Thrombasthenia is a rare bleeding disorder that is characterized by inhibition of glycoprotein IIb/IIIa signaling, usually by an autoantibody, leading to an interference in platelet aggregation. Clinically, this disorder presents with spontaneous mucocutaneous bleeding in the setting of a normal platelet count. Acquired Glanzmann Thrombasthenia has been associated with primary immune thrombocytopenic purpura (ITP), several types of hematologic and solid malignancies, solid organ transplants, and other autoimmune disorders. Methods/Case Report A 4-year-old female patient with a history of Alagille Syndrome requiring liver transplant at age 3 was admitted to the hospital after presenting to the emergency department with complaints of bruising, nosebleeds, and a petechial rash. The patient was found to have a platelet count of 11 K/mm3 and was diagnosed with ITP. The patient received a single dose of IVIG at 1g/kg with subsequent resolution of bleeding and a recovering platelet count of 27 K/mm3 12 hours after administration. However, two months later, the patient presented again with worsening bruising, multiple nosebleeds per day, and worsening petechiae. Lab studies revealed the patient’s platelet count was within normal limits. A platelet antibody screen was positive with a subsequent Platelet Antibody Bead Array revealing anti-Gp IIb/IIIa HPA-1 and HPA-3 positivity. Results (if a Case Study enter NA) N/A Conclusion Acquired Glanzmann Thrombasthenia is a rare bleeding disorder that is the result of interference with platelet aggregation. Antibodies that may be associated with any of several underlying conditions lead to impaired platelet function and subsequent mucocutaneous bleeding. The present case represents an occurrence of Acquired Glanzmann Thrombasthenia in a patient with multiple risk factors for development of the disorder.


1973 ◽  
Vol 29 (02) ◽  
pp. 490-498 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Itsuro Kobayashi ◽  
Tadahiro Sano ◽  
Takio Shimamoto

SummaryThe authors previously reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of a small amount of adrenaline (0.1-1 µg per Kg, i. v.) in man and rabbit. In such circumstances, the sensitivity of platelets to aggregation induced by ADP was studied by an optical density method. Five minutes after i. v. injection of 1 µg per Kg of adrenaline in 10 rabbits, intensity of platelet aggregation increased to 115.1 ± 4.9% (mean ± S. E.) by 10∼5 molar, 121.8 ± 7.8% by 3 × 10-6 molar and 129.4 ± 12.8% of the value before the injection by 10”6 molar ADP. The difference was statistically significant (P<0.01-0.05). The above change was not observed in each group of rabbits injected with saline, 1 µg per Kg of 1-noradrenaline or 0.1 and 10 µg per Kg of adrenaline. Also, it was prevented by oral administration of 10 mg per Kg of phenoxybenzamine or propranolol or aspirin or pyridinolcarbamate 3 hours before the challenge. On the other hand, the enhancement of ADP-induced platelet aggregation was not observed in vitro, when 10-5 or 3 × 10-6 molar and 129.4 ± 12.8% of the value before 10∼6 molar ADP was added to citrated platelet rich plasma (CPRP) of rabbit after incubation at 37°C for 30 second with 0.01, 0.1, 1, 10 or 100 µg per ml of adrenaline or noradrenaline. These results suggest an important interaction between endothelial surface and platelets in connection with the enhancement of ADP-induced platelet aggregation by adrenaline in vivo.


1978 ◽  
Vol 39 (02) ◽  
pp. 346-359 ◽  
Author(s):  
P D Winocour ◽  
M R Turner ◽  
T G Taylor ◽  
K A Munday

SummaryA major limitation to single-cell protein (SCP) as a human food is its high nucleic acid content, the purine moiety of which is metabolised to uric acid. Rats given a Fusarium mould as a source of SCP in diets containing oxonate, a uricase inhibitor, showed elevated plasma and kidney uric acid concentrations after 21 d, which were related to the level of dietary mould. ADP-induced and thrombin-induced platelet aggregation was greater in the hyperuricaemic rats than in controls and a progressive increase in aggregation with increasing levels of dietary mould was observed. Furthermore a time-lag, exceeding the life-span of rat platelets, was observed between the development of hyperuricaemia and the increase in aggregation. A similar time-lag was observed between the lowering of the hyperuricaemia and the reduction of platelet aggregation when oxonate was removed from the diet.If human platelets react to uric acid in the same manner as rat platelets this might explain the link that has been suggested between hyperuricaemia and ischaemic heart disease. In that event diets high in nucleic acids might be contra-indicated in people at risk from ischaemic heart disease.In rats given a low protein diet (50 g casein/kg) for 21 d ADP-induced and thrombin-induced platelet aggregation and whole blood platelet count were reduced compared with control animals receiving 200 g casein/kg diet but not in rats given 90 or 130 g casein/kg diet. A study of the time course on this effect indicated that the reduction both in aggregation tendency and in whole blood platelet count occurred after 4 d of feeding the low protein diet. These values were further reduced with time.


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