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Bernard-Soulier disease (giant platelet syndrome, benign Mediterranean macrothrombocytopenia)

Etiology: deficiency in platelet glycoprotein Ib/IX [3] Epidemiology: 1) rare disorder 2) more common in whites & blacks Pathology: - congenital platelet defects - decreased platelet adhesion - platelets cannot bind von Willebrand factor (vWF) Genetics: - autosomal dominant (benign Mediterranean macrothrombocytopenia) - recessive inheritance - associated with defects in platelet GP-1b-alpha (GP1BA, CD42a) - associated with defects in platelet GP-1b-beta (GP1Bb, CD42b) Clinical manifestations: 1) moderate to severe bleeding with surgery & menstruation 2) bleeding generally occurs from: a) mucous membranes b) gums c) gastrointestinal tract 3) autosomal dominant form (benign Mediterranean macrothrombocytopenia) - mild or no clinical symptoms Laboratory: 1) thrombocytopenia with giant platelets 2) bleeding time is markedly prolonged 3) platelet aggregation a) opposite to that of Glanzmann's thrombasthenia a) normal response to ADP, collagen, epinephrine & thrombin b) no aggregation with ristocetin 4) normal levels of von Willebrand factor (vWF) 5) autosomal dominant form (benign Mediterranean macrothrombocytopenia) a) normal platelet function b) normal megakaryocyte count in bone marrow biopsy Management: - platelet transfusions for active bleeding as needed - epsilon-aminocaproic acid for active bleeding as needed [3]

Related

platelet glycoprotein 1b von Willebrand factor; vWF; ristocetin cofactor; factor VIII related antigen; contains: von Willebrand antigen 2 (VWF, F8VWF)

General

platelet disorder; thromboasthenia

Database Correlations

OMIM correlations

References

  1. MedStudy
  2. Mayo Internal Medicine Board Review, 1998-99, Prakash UBS (ed) Lippincott-Raven, Philadelphia, 1998, pg 439
  3. Medical Knowledge Self Assessment Program (MKSAP) 11, 17, 18. American College of Physicians, Philadelphia 1998, 2015, 2018