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Bleeding History • Site of bleed • Duration of bleed • Precipitating causes, including previous surgery or trauma • Family history • Drug history • Age at presentation • Other medical conditions, e.g. liver disease Examination There are two main patterns of bleeding: 1. Mucosal bleeding Reduced number or function of platelets (e.g. bone marrow failure or aspirin) or von Willebrand factor (e.g.von Willebrand disease) Skin: petechiae, bruises Gum and mucous membrane bleeding Fundal haemorrhage Post-surgical bleeding 2. Coagulation factor deficiency (e.g. haemophilia or warfarin) Bleeding into joints (haemarthrosis) or muscles Bleeding into soft tissues Retroperitoneal haemorrhage Intracranial haemorrhage Post-surgical bleeding Vessel wall abnormalities Vessel wall abnormalities; congenital, such as hereditary haemorrhagic telangiectasia • acquired, as in a vasculitis or scurvy Hereditary haemorrhagic telangiectasia(HHT) Autosomal dominant . Telangiectasia and small aneurysms are found on the fingertips, face and tongue, and in the nasal passages,lung and gastrointestinal tract. Pulmonary arteriovenous malformations (PAVMs) that cause arterial hypoxaemia due to a right-to-left shunt. These predispose to paradoxical embolism, resulting in stroke or cerebral abscess. = All patients with HHT should be screened for PAVMs; if these are found, ablation by percutaneous embolisation should be considered. • Recurrent bleeds, particularly epistaxis, or with iron deficiency due to occult gastrointestinal bleeding. TREATMENT • 1-Iron replacement for IDA 2-Local cautery or laser therapy may prevent single lesions from bleeding • Platelet function disorders Primary Hemostasis Platelet Plug formation Dependent on normal platelet number & function Initial manifestation of clot formation 1-Thrombocytopenia 2-Thrombasthenia Thrombasthenia Congenital • Deficiency of the membrane glycoproteins Glanzmann’s thrombasthenia (IIb/IIIa) Bernard–Soulier disease (Ib) Defective platelet granules deficiency of dense (delta) granule (storage pool disorders) Macrothrombocytopathies Alport`s syndrome Acquired • Iatrogenic; • Aspirin ;cyclo-oxygenase inhibitor Clopidogrel; adenosine inhibitor Dipyridamole;phosphodiesterase inhibitor Abciximab; IIb/IIIa inhibitor Laboratory Tests for Primary Hemostasis Function Platelet count Bleeding time Platelet Aggregation Studies clot retraction Flow cytometric studies for Glycoproteins Glanzmann thrombasthenia Background: Pathophysiology: Thrombasthenia was first describe in 1918 by Glanzmann when he noted purpuric bleeding in patients with normal platelet counts Typically, thrombasthenia is diagnosed at an early age Autosomal recessive trait The production and assembly of the platelet membrane glycoprotein IIb-IIIa is altered, preventing the aggregation of platelets and subsequent clot formation Treatment 1-local measure.2-antifibrinolytic agent such as tranexamic acid .3-platelet transfusion.4-Recombinant factor VII Idiopathic thrombocytopenic purpura Autoantibodies, most often directed against the platelet membrane glycoprotein IIb/IIIa, which sensitise the platelet, resulting in premature removal from the circulation by cells of the reticulo-endothelial system. 1-Isolated condition. 2-Association with connective tissue diseases,HIV infection, B cell malignancies, pregnancy and certain drug therapies. Clinical features Classification of ITP disease phases ITP phase Definition Newly diagnosed Persistent Chronic Within 3 months of diagnosis 3 to 12 months from diagnosis > 12 months from diagnosis In adults, ITP usually has an insidious onset, with no preceding illness. Nearly one-quarter of patients present asymptomatically and receive a diagnosis of ITP through incidental routine blood tests Petechiae or purpura • Unusual or easy bruising (haematoma)• Persistent bleeding symptoms from cuts or other injuries• Mucosal bleeding• Frequent or heavy nose bleeds (epistaxis) • Haemorrhage from any site (usually gingival or menorrhagia in womenn Purpura and haematomas Mucosal bleeding Petechie Recommended diagnostic approaches for ITP Patient history Family history Physical examination Complete blood count and reticulocyte count Peripheral blood smear Quantitative immunoglobulin level measurement* Bone marrow examination (in selected patients) Blood group (rhesus) Direct antiglobulin test Helicobacter pylori Human immunodeficiency virus (HIV) Hepatitis C virus (HCV) Bone marrow aspiration is indicated in older patients (particularly those over 60 years of age to exclude myelodysplastic syndrome), in those with an atypical presentation (e.g. abnormalities observed on peripheral blood smear suggestive of other haematological disorders), in those with a poor response to first-line therapy and in those being considered for splenectomy.. Treatment when to treat? If a patient has two relapses,or primary refractory disease, splenectomy is considered. Splenectomy produces complete remission in about 70% of patients and improvement in a further 20–25%, so that,following splenectomy, only 5–10% of patients require further medical therapy. Second-line therapy with the thrombopoietin analogue romiplostim or the thrombopoietin receptor agonist eltrombopag Rituximab, ciclosporin and tacrolimus should be consideredin cases where the approaches above are ineffective. Coagulation disorders Clinical Features of Bleeding Disorders Platelet disorder Coagulation disorders Site of bleeding Skin Deep in soft tissues Mucous membranes (joints, muscles) (epistaxis, gum, vaginal, GI tract) Petechiae Yes Ecchymoses (“bruises”) Small, superficial Large, deep Hemarthrosis / muscle bleeding Extremely rare Common Bleeding after cuts & scratches Yes No Bleeding after surgery or trauma Severity Immediate, usually mild No Delayed (1-2 days), often severe Haemophilia A Clinical features A prolonged aPTT: a normal aPTT does not exclude mild hemophilia A because the aPTT may not be sufficiently sensitive to detect slightly reduced levels of FVIII-C in the approximate 20-30% range Normal PT Treatment • Replacement of missing coagulation factor o Clotting factor replacements Clotting factor concentrates (CFCs) Plasma-derived Recombinant FVIIa Cryoprecipitate in developing countries o Other pharmacologic agents Desmopressin (DDAVP) Anti-fibrinolytic agent Tranexamic acid 8-aminocaproic acid (EACA) o Supportive measures Rest Ice Compression Elevation Two main Treatment Modalities *On -demand **Prophylaxis Complication of clotting factor therapy - Infection; HIV, HBV, HCV - Anti factor VIII inhibitor in 20 % , treated by infusion of activated factor VIIa OR factor VIII inhibitor bypass activity (FEIBA) Optimal dosage according to the site of Haemorrhag Site of haemorrhage Optimal factor level Dose (U/Kg BW) Duration (days) Joint 30-50 15-25 1-2 Muscle 30-50 15-25 1-2 GIT 40-60 30-40 7-10 Oral mucosa 30-50 15-25 Until healing Epistaxis 30-50 15-25 Until healing Hematuria 30-50 15-25 Until healing CNS 80-100 50 10-21 Retroperitoneal 50-100 30-50 7-14 Trauma/Surgery 50-100 30-50 Until healing Haemophilia B (Christmas disease) • Due to deficiency of factor IX . • X-linked • Clinical manifestation indistinguishable from haemophilia A • Treatment ; factor IX concentrate , indication and dosing same as to haemophilia A. • Complication of therapy similar to haemophilia A regarding transmission of infection BUT the incidence of inhibitor is < 1%. Von Willebrand disease von Willebrand factor – Synthesis in endothelium and megakaryocytes – Forms large multimer – Carrier of factor VIII – Anchors platelets to subendothelium – Bridge between platelets Lab Studies: Screening tests typically include prothrombin time (PT) activated partial thromboplastin time (aPTT), FVIII level ristocetin cofactor (RCoF) activity vWF antigen (vWF:Ag). Laboratory evaluation of von Willebrand disease Classification – Type 1 – Type 2 – Type 3 Partial quantitative deficiency Qualitative deficiency Total quantitative deficiency *Bleeding time ↑ *aPTT ↑ vWD type Assay vWF antigen vWF activity Multimer analysis 1 Normal 2 Normal Abnormal 3 Absent Disseminated intravascular coagulation (DIC) DIC is a clinicopathologic syndrome in which widespread intravascular coagulation is induced by procoagulant that are introduce or produce in circulation and overcome the natural anticoagulant mechanisms. DIC may cause tissue ischemia from occlusive microthrombi as well as bleeding from both consumption of platelet and coagulation factor and anticoagulation effect of product of secondary fibrinolysis Disseminated Intravascular Coagulation (DIC) Mechanism Systemic activation of coagulation Intravascular deposition of fibrin Thrombosis of small and midsize vessels with organ failure Depletion of platelets and coagulation factors Bleeding Pathogenesis of DIC Release of thromboplastic material into circulation Coagulation Consumption of coagulation factors; Fibrinolysis Fibrinogen Plasmin Thrombin Fibrin Monomers Fibrin Clot (intravascular) Fibrin(ogen) Degradation Products Plasmin aPTT PT TT Fibrinogen Presence of plasmin FDP Intravascular clot Platelets Schistocytes MAHA DIC Treatment Treatment of underlying disorder Platelet transfusion (6-10 U plat (ideally rise to more than 50000-100000 Fresh frozen plasma;1-2 unit For coagulation factor depletion Hypofibrinogenaemia; Anticoagulation 8-10 U cryopercipitate with heparin; unless there is a clear contraindication Coagulation inhibitor concentrate (ATIII) Patients with DIC should not be treated with antifibrinolytic therapy, e.g.tranexamic acid. Thrombotic thrombocytopenic purpura(TTP) thrombosis is accompanied by paradoxical thrombocytopenia, TTP is characterised by a pentad of findings, although few patients have all five components: • thrombocytopenia • microangiopathic haemolytic anaemia(MAHA) • neurological sequelae • fever • renal impairment TTP-Cont. It is an acute autoimmune disorder mediated by antibodies against ADAMTS-13 (a disintegrin and metalloproteinase with a thrombospondin type-1 motif). It is a rare disorder (1 in 750 000 per annum), which may occur alone or in association with drugs (ticlopidine, ciclosporin), HIV, shiga toxins and malignancy. It should be treated by emergency plasma exchange. Corticosteroids, aspirin and rituximab also have a role in management Untreated mortality rates are 90% in the first 10 days, and even with appropriate therapy, the mortality rate is 20–30% at 6 months THROMBOTIC DISORDERS Virchow’s Triad Pathogenesis of a Thrombus Endothelial injury Abnormal blood flow Hypercoagulability Genetic acquired Signs & Symptoms DVT: 50% with no clinical signs ?Edematous extremity Plethoric,Warm,Painful extremity PE: Cough, SOB, Hemoptysis Tachycardia Thrombophilia Hereditary Thrombophilias Physiologic Inhibitors of Protein C pathway coagulation Factor V Leiden Antithrombin Protein C deficiency Activated Protein C + protein S Protein S deficiency Inactivates Va and VIIIa (via Prothrombin G20210A proteolysis) mutation Thrombomodulin Antithrombin deficiency Binds to thrombin Hyperhomocystinemia activate Protein C C677T MTHFR mutation Hereditary Thrombophilias None of them is strongly associated with arterial thrombosis. • All are associated with a slightly increased incidence of adverse outcome of pregnancy,including recurrent early fetal loss, but there are no data to indicate that any specific intervention changes that outcome. • Apart from in antithrombin deficiency and homozygous factor V Leiden, most carriers of these genes will never have an episode of VTE; if they do, it will be associated with the presence of an additional temporary risk factor. • There is little evidence that detection of these abnormalities predicts recurrence of VTE. • None of these conditions per se requires treatment with anticoagulants Antiphospholipid Antibody Syndrome Autoimmune Acquired Prothrombotic Disorder Very High Risk for recurrent thromboembolic disease both venous and arterial Indefinite duration anticoagulation recommended +/immunosuppression Strict Diagnostic Criteria Antiphospholipid Syndrome Clinical criteria (≥1 must be present): 1.Vascular thrombosis: - ≥ 1clinical episode of, objectively confirmed, arterial, venous, or small vessel thrombosis 2. Pregnancy morbidity: - ≥ 1 unexplained fetal death @ ≥ 10 weeks EGA - ≥ 1 premature birth (≤ 34th week of gestation) due to eclampsia, severe pre-eclampsia, or placental insufficiency - ≥ 3 unexplained consecutive spontaneous abortions @ <10 weeks EGA Revised Sapporo/Sydney Criteria. JTH 2006;4:295-306 Antiphospholipid Syndrome Laboratory criteria (≥1 must be present): Lupus anticoagulant {LA} (+) ≥ 2 occasions, at least 12 weeks apart, according to ISTH guidelines: prolonged aPTT, lack of correction with 1:1 mix, and correction with Anticardiolipine antibody(ACLA) and/or anti-β2 glycoprotein-I antibody: medium or high IgG and/or IgM isotype titer ≥ 2 occasions, at least 12 weeks apart Standardized ELISA assays Revised Sapporo/Sydney Criteria. JTH 2006;4:295-306