An Approach to a Patient with Bleeding Disorder

CHAPTER An Approach to a Patient with Bleeding Disorder 62 Nidhi Sharma, Sandhya Gulati, Sudhir Mehta, Shaurya Mehta ABSTRACT History taking: A good detailed comprehensive history is Hemorrhagic diathesis can be caused by disorders in the best predictor of a bleeding problem. primary hemostasis (von Willebrand disease, inherited NATURE OF BLEEDING platelet function disorders), secondary hemostasis If the bleeding involves the skin (cutaneous) and mucous (hemophilia A, B, other coagulant factor deficiencies) membranes i.e. petechiae, purpura bruises, epistaxis, and fibrinolysis, and in connective tissue or vascular gingival bleeding, menorrhagia and/or hematuria, it formation. This review summarizes the approach to would suggest a platelet and/or vascular abnormality. a bleeding patient starting from structured patient Bleeding into deep tissue, joints and muscles suggest a history, to applying bleeding assessment tools (BATs), coagulation factor defect4. the utilization of currently available diagnostic methods for bleeding disorders and finally investigating with HISTORY SUGGESTING CONGENITAL/ACQUIRED BLEEDING highly specialized tests. A comprehensive framework A history of easy bruising or exaggerated bleeding after for a genetic diagnostic work up to inherited bleeding injury suggests an inherited bleeding problem. There disorders is the need of the hour. The discovery of a wide should be questions on any childhood history of epistaxis, spectrum of mutations in the various genes associated umbilical stump bleeding, bleeding after circumcision with coagulation and their association with different hinting an inherited bleeding disorder. Any history of severity of the disease has allowed for the development blood transfusion or other blood components is very of a rational strategy for mutation detection in clinical important. Information on all surgeries including tooth settings. Characterization of the genetic defects is also extractions and any history of abnormal bleeding during required for carrier detection, antenatal testing, and or after surgery should be evaluated. The response to predicting risk of factor inhibitor development. trauma is an excellent screening test. Any significant injury KEYWORDS without abnormal bleeding is good evidence against the presence of an inherited haemorrhagic disorder. bleeding disorder, approach, investigations, genetics A very careful family history is critical; any family history INTRODUCTION of abnormal bleeding in parents, maternal grandparents, Hemostasis involves interactions between the blood aunts, uncles, and siblings as well as any history of vessels, platelets and coagulation factors1. A defect in any consanguineous marriage (or among relatives) should be of these phases of coagulation can result in a bleeding taken. However, a negative family history does not exclude problem which may be inherited or acquired. The aim of an inherited coagulation disorder. As an example, up to hemostasis is to prevent blood loss following injury by the 30-40% of patients with hemophilia A have a negative formation of a stable blood clot. Blood clots are eventually family history. A comprehensive history will guide the dissolved by the fibrinolytic system. A delicate balance direction and extent of the laboratory evaluation and also between formation and dissolution of a blood clot is help in determining management. maintained2,3. A disruption of this unique balance results in bleeding or thrombosis. The objectives of this review MEDICATION USE is to provide primary care physicians with a systematic A careful history of medication use is important, diagnostic approach in dealing with patients suffering including prescribed medications, over-the-counter from bleeding disorders, and demonstrate the importance medications and herbal products. Drugs cause bleeding of clinical and laboratory evaluation as highlighted in due to thrombocytopenia or platelet dysfunction, aplastic Table 1. anemia or vascular purpura. Table 1: Evaluation of a patient with bleeding disorder Bleeding scores (BSs) have been proposed for obtaining standardized quantitative histories5. Because symptoms Clinical History might be subtle, especially in younger children, a detailed evaluation Family history clinical history is crucial. In order to standardize this, Bleeding assessment tools (BATs) questionnaires have been drafted and are known as Physical examination bleeding assessment tools (BATs). The main advantages Laboratory First line investigations (screening tests) of using BATs are: evaluation Second line investigations (confirmatory 1. As a screening tool, particularly for mild bleeding test) disorders. Third line investigations (genetic workup) 340 2. To assess disease severity. occurring” platelet autoantibody directed against a 3. To address phenotypic heterogeneity and normally concealed epitope on the platelet membrane, correlations between clinical and laboratory which becomes exposed by EDTA. Use of alternative phenotype, and between genotype and phenotype anticoagulants (eg, citrate or heparin), may circumvent this technical problem. 4. To improve communication in a clinical setting. Bleeding time — The bleeding time (BT) is a measure of PHYSICAL EXAMINATION the interaction of platelets with the blood vessel wall. A From the clinical assessment, one should be able to assess prolonged bleeding time may occur in thrombocytopenia whether: (1) the bleeding is the result of a local anatomic (platelet count usually below 50,000/microL), qualitative defect or part of a systemic defect in hemostasis, (2) the platelet abnormalities (eg, uremia), von Willebrand bleeding is due to a vascular defect, platelet abnormality disease (VWD), some cases of vascular purpura, and or coagulation disorder, or (3) the haemostatic defect is severe fibrinogen deficiency, in which it is probably inherited or acquired. the result of platelet dysfunction. Among patients with a normal platelet count who are not taking aspirin, the DISORDERS OF PLATELETS OR BLOOD VESSELS bleeding time is used primarily to screen patients for They are characteristically associated with mucosal inherited disorders of platelet function. An abnormal test HAEMATOLOGY (epistaxis, gingival) and cutaneous bleeding (petechiae, in a patient with mucocutaneous bleeding would justify ecchymoses). Patients with platelet abnormalities tend further testing for platelet dysfunction or specific tests for to bleed immediately after vascular trauma and rarely von Willebrand disease (VWD). However, a normal value experience delayed bleeding, which is more common in for the BT should not preclude testing for VWD. Platelet the coagulation disorders. Function Analyzer is more sensitive for detection of VWD COAGULATION DISORDERS than is the BT. The typical manifestations of bleeding in the coagulation A normal BT does not predict the safety of surgical disorders are large palpable ecchymoses and large procedures, nor does an abnormal BT predict for spreading deep soft tissue hematomas. Haemorrhage excessive bleeding. Since assessment of the BT is subject into synovial joints most often indicates a severe inherited to considerable variation due to technical factors in coagulation disorder such as hemophilia. executing the test, a normal range for the test varies LABORATORY INVESTIGATIONS from laboratory to laboratory, and cannot be generalized here. Of importance, the BT is not recommended as a For each phase of hemostasis, screening tests which help preoperative screening test. Because of considerable in distinguishing a platelet disorder from a coagulation variation due to technical factors in executing the test, the defect are available. The use of these tests are never a BT plays a limited role, if any, in evaluating hemostatic substitute for clinical assessment, as there is enough defects. evidence that screening tests are unhelpful in the prediction of a bleeding disorder especially when applied The Platelet Function Analyzer — The commercially- indiscriminately. The quality of the report issued from available Platelet Function Analyzer (PFA-100) is an the laboratory will depend on the quality of the sample. alternative technology that assesses platelet function with Clotted, hemolyzed and inappropriately collected sample greater sensitivity and reproducibility than the bleeding will lead to erroneous results. Sodium citrate is the anti- time (BT). Because the BT is insensitive, invasive, time coagulant of choice. consuming, and subject to variation due to technical factors, many centers have adopted the PFA-100 in place First line investigations (screening tests) include a of the BT as their screening test of platelet function. This complete blood count (CBC) to assess platelet count, test may be performed on citrated samples of whole peripheral blood smear examination, prothrombin time blood that have been stored at room temperature, and is (PT), activated partial thromboplastin time (APTT), a considerably faster to perform than platelet aggregation thrombin time (TT) and a bleeding time (BT) or platelet studies. Normal PFA-100 test results may obviate the need function analysis (PFA)6,7,8. Second line investigations for further expensive platelet function testing. Unlike the include mixing studies, factor levels, platelet aggregation in vivo BT, the PFA-100 test does not provide a measure studies and von Willebrand factor level. of vascular function. Platelet counting and the peripheral smear — Platelets Prothrombin time — The production of fibrin via the may be counted

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