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Coagulation Disorders
Awareness of Mild Bleeding Disorders
a report by
Pieter W Kamphuisen
Department of Vascular Medicine, Academic Medical Centre, Amsterdam
Inherited bleeding disorders are rare in the general population. Table 1: What Questions Should Be Asked to Investigate a
Nevertheless, the most common bleeding disorders, haemophilia and von
Bleeding Diathesis?
Willebrand disease (VWD), occur in one in 5,000 males and 1% of the
Is a pathological bleeding tendency present?
general population.
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Since fibrin formation or platelet aggregation in these
Is it congenital/familial or acquired?
patients is insufficient, prophylaxis with clotting factor concentrate or
Is it principally a defect of primary haemostasis or of fibrin formation?
desmopressin (DDAVP) prevents severe bleeding complications in situations
Is there a systematic disease causing or exacerbating any bleeding tendency?
where optimal haemostasis is crucial, such as surgery. Most patients with In the increased bleeding tendency induced or exacerbated by medication?
either haemophilia or VWD have a relatively mild phenotype, and their
disease may well become apparent only after abnormal bleeding post- For instance, the majority of women with menorrhagia do not have a
operatively. In addition, many patients may not be aware of having a bleeding disorder, and gynaecological evaluation is required to evaluate
bleeding abnormality, since relatives may have the same symptoms. other causes of bleeding even in women with a known bleeding disorder.
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Therefore, it is of the utmost importance to identify patients with In a situation where physicians actively screen patients for bleeding
underlying bleeding disorders before they undergo surgery. In particular, disorders, the correlation between coagulation abnormalities as measured
dentists, gynaecologists and paediatricians should investigate patients for in the plasma and the severity of bleeding symptoms is usually very low.
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potential bleeding abnormalities. Therefore, the predictive value of an abnormal clotting test alone has
hardly any value. Considering these complexities in both clinical and
In general, patients with haemophilia can be distinguished from those with laboratory diagnosis, a systematic approach to the diagnosis of bleeding
VWD by the difference in bleeding symptoms. VWD is caused by a disorders is a prerequisite.
deficiency in or a dysfunction of von Willebrand factor (VWF). VWF is a
multimeric protein synthesised in megakaryocytes and endothelial cells. It The clinical approach usually consists of taking a complete medical history
has two main haemostatic functions. In primary haemostasis at the site of and laboratory screening tests. However, there is very little evidence
injured vessel walls, it facilitates platelet adhesion to subendothelial assessing the diagnostic efficacy of clinical history-taking or laboratory
structures, such as exposed collagen fibres, and supports platelet screening in order to predict an individual’s bleeding risk or to guide clinical
aggregation and thrombus formation. As part of secondary haemostasis, management. Nevertheless, it will be worthwhile to identify subjects at risk
VWF acts as a carrier protein for coagulation factor VIII, stabilising and of excessive bleeding with the use of a simple bleeding history in
protecting factor VIII pro-coagulant activity. Since VWD has an autosomal combination with basic laboratory tests.
dominant inheritance pattern, both men and women can be affected.
Individuals with VWD are at increased risk of mucocutaneous bleeding Taking Medical History for Bleeding Disorders
including epistaxis, easy bruising, prolonged bleeding after trivial cuts and A bleeding history should consist of questions regarding the location and
dental procedures and reproductive tract bleeding, notably menorrhagia.
1,3
severity of bleeding, familial tendency, co-morbidity and medication such as
Haemophilia is an X-linked recessive disorder caused by a partial or non-steroidal anti-inflammatory drugs (NSAIDs) or aspirin. Table 1 depicts
complete deficiency of clotting factor VIII (haemophilia A) or factor IX five important items that should be addressed to investigate the presence of
(haemophilia B). Males are typically affected, and bleeding mostly occurs in an increased bleeding tendency.
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A pathological bleeding tendency can
joints and muscles. consist of large haematomas, menorraghia (preferably since menarche),
frequent nose and other mucosal bleeds, easy bruising and excessive
How Can Patients with Mild Bleeding bleeding after surgery or trauma. Tonsillectomy or tooth extractions are two
Disorders Be Detected? examples of frequently occurring forms of surgery that may induce a severe
First, one has to be certain that bleeding manifestations are due to an bleeding. A thorough investigation of bleeding symptoms during the whole
abnormal bleeding diathesis. This is not simple, since the discrimination lifetime should be undertaken, preferably based on objective information.
between patients with mild bleeding disorders and normal subjects is For instance, the physician could ask about the maximum size of
often unclear. In the case of evaluation of a bleeding disorder, patients can ecchymoses or the number of tampons used during menstrual cycles;
be referred because of abnormal bleeding or physicians can actively screen pictorial charts have also been proposed to assess the amount of menstrual
patients pre-operatively for a defect in haemostasis. In the first instance, blood losses better.
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As a negative bleeding history could also be relevant for
patients themselves may have suffered from excessive bleeding after the exclusion of a bleeding tendency, all instances of surgery or tooth
trauma or surgery or have spontaneous bleeding or a family history of extraction should also be recorded, even if no haemorrhages occurred.
increased bleeding tendency. One should remember that most of the Finally, subjects should also be asked about the type of medical intervention
time, bleeding symptoms are not caused by a specific bleeding disorder.
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that was required to control bleeding episodes.
12 © TOUCH BRIEFINGS 2008
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