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Excessive bruising and
Abdome
— Splenomegal
— Hepatomegaly
Muscl
— Haematom
Joints
— Deformity
— Hyperextensibility
— Haemarthrosis
Skin
— Petechiae
— Purpura
— Ecchymoses
—
Eyes
Lymph nodes
— Conjunctival pallor
Mouth
— Hereditary haemorrhagic
INTRODUCTION
Excessive bruising and bleeding (prolonged, spontaneous
or following an insignificant injury) arise when there is
abnormal haemostasis; this may occur because of abnormalities of the coagulation pathway, abnormalities of platelet number or function, or abnormalities of the blood vessel
(e.g. fragility of the vessel wall).
HISTORY AND EXAMINATION FINDINGS
When taking the history of and examining the patient with
abnormal bleeding, it is important to maintain a general approach with specific focus on the characteristics of bleeding.
When you are concentrating on the history, certain points
should be emphasized and these include:
• The pattern and extent of bleeding and bruising.
• Platelet abnormalities (deficiency or dysfunction)
• Vessel wall abnormalities cause petechiae and
• Coagulopathies cause haemarthrosis, muscle
• The underlying cause:
• Bleeding and bruising: determine whether it is
• Liver disease: intrinsic liver disease (coagulopathy)
• Drug history: blood thinning medication, including
• Symptoms of underlying bone marrow failure (e.g.
• Hyperextensibility of the skin or joints: Ehlers–
• Known AIDS or risk factors for HIV infection.
• Have complications occurred?
• Evaluate the severity of bleeding.
• Establish symptoms of anaemia.
cause skin or mucosal purpura and haemorrhage.
There is prolonged bleeding following minor
procedures or trauma.
ecchymoses due to bleeding from small vessels.
These are usually in the skin but are also in mucous
membranes.
haematomas, postoperative or traumatic bleeding
and palpable ecchymoses. If inherited they present
early in life.
within the spectrum of ‘normal’ (e.g. related to
trauma or recent haemostatic abnormality).
or biliary obstruction may cause reduced platelet
function and vitamin K deficiency.
aspirin, clopidogrel, heparin and warfarin, steroids
or previous chemotherapy.
recurrent infection, symptoms of anaemia).
Danlos syndrome, pseudoxanthoma elasticum.
bleeding
26
• Musculoskeletal symptoms (muscle and joint pain,
and deformity).
HINTS AND TIPS
Von Willebrand factor is necessary for platelet
adhesion and prevents degradation of factor VIII. Von
Willebrand factor deficiency causing von Willebrand
disease may therefore cause bleeding consistent
with both platelet abnormalities and coagulopathy.
Examination should be approached in a similar manner to
history taking. Fig. 26.1 summarizes the examination approach. Features to concentrate on include:
• the pattern and extent of bruising and bleeding;
• the sites and types of lesions (petechiae are smaller
than 2 mm, characterized by pinpoint bleeding into
telangiectasia
— Mucosal petechiae/
haemorrhage
Lymphadenopathy
n
y
e
a
General
— Site and extent of bleeding/bruising
— Cushingoid appearance
— Hereditary haemorrhagic telangiectasia
— Signs of liver disease
— Poor wound healing
Fig.26.1 Examining the patient with bruising and bleeding.
Blood pressure
and pulse
— Shock
Hands
— Signs of liver
disease
159
Excessive bruising and bleeding
skin or mucosa; ‘purpura’ denotes bruises between
2 mm and 1 cm; ‘ecchymosis’ refers to anything larger
than 1 cm).
• whether there are signs suggestive of a specific
underlying cause (e.g. liver disease);
• how severe the bleeding has been and if there are
complications.
• Look for evidence of anaemia, which may be due to
chronic bleeding or an acute haemorrhage. Finally, look
for joint deformities (haemarthrosis) or a muscle mass
(haematoma).
INVESTIGATIONS
When an abnormality of haemostasis is suspected, a full
blood count (FBC) and simple coagulation assays should be
performed first. More specific tests to diagnose the underlying cause can then be considered. Fig.26.2 summarizes the
normal coagulation pathway.
An algorithm for investigating the patient with bruising
and bleeding is given in Fig.26.3.
Common blood tests are described below and summarized in Table26.1. FBC and blood film may detect lym-
phoma, leukaemia, thrombocytopenia or abnormal platelet
levels. Checking renal function may detect an abnormal
urea level that can cause platelet disorder. Liver function
tests will detect a hepatic cause of abnormal bleeding, such
as alcohol abuse or acquired platelet disorders.
Recommended coagulation studies include:
• Prothrombin time (PT), which measures the extrinsic
system (tissue factor and factor VII) and the final
common pathway. It is prolonged in liver disease
and with warfarin therapy, and is generally
expressed as the international normalized
ratio (INR).
• Activated partial thromboplastin time (APTT), which
measures the intrinsic system (factors VIII, IX, XI
and XII) and the common pathway (fibrinogen,
prothrombin and factors V and X). It is prolonged with
unfractionated heparin therapy (not low-molecularweight heparins) and deficiency of factors such as
factor VIII (haemophilia A) and factor IX (haemophilia
B, Christmas disease), and measures overall
competence of the coagulation system.
• Thrombin time (TT), which measures the rate of clot
formation and therefore the activity of thrombin and
fibrinogen in the common pathway. It is prolonged in
disseminated intravascular coagulation (DIC) or in
other conditions causing fibrinogen deficiency (e.g.
liver disease).
• The levels of fibrin degradation products, including
D-dimers. The levels will be grossly elevated in DIC
and may be raised in other conditions, including
malignancy, renal disease and sepsis.
If these tests do not show an abnormality, most common
bleeding disorders would have been excluded. Further tests
to elucidate the nature of the problem include:
Intrinsic activation Extrinsic activation
Exposed collagen
XII
Fig.26.2 The normal coagulation pathway.
XIIa
XI XIa
IX IXa
Common
pathway
160
2+
Ca
Phospholipid
VIII
X Xa
Prothrombin
Tissue factor
VIIa VII
V
Fibrinogen
Thrombin
Fibrin
Bruising and bleeding
Investigations
2626
Recurrent, severe or spontaneous
Prolonged bleeding after trauma,
Normal
abnormality
episodes
surgery or dentistry
Possible haemostatic
abnormality
Normal platelet count
and clotting
Platelet function assay
results
Vessel
Abnormal
results
vWD
platelet
dysfunction
History
Examination
Platelet count
PT
APTT
TT
Abnormal
anticoagulation
test results
Single episode
due to trauma
No further tests
Thrombocytopenia
Repeat to exclude artefact
Blood film
Bone marrow aspirate
Marrow failure
Platelet consumption
Increased APTT Increased TTIncreased PT
Liver disease
Warfarin
Vitamin K deficiency
Heparin
DIC
Haemophilia A + B
Heparin
DIC
Fibrinogen
dysfunction
Fig.26.3 Algorithm for investigating the patient with bruising or bleeding. APTT, Activated partial thromboplastin time;
DIC, disseminated intravascular coagulation; PT, prothrombin time; TT, thrombin time; vWD, von Willebrand disease.
• Platelet function analyser (PFA), which measures
platelet adhesion and aggregation and has replaced
the bleeding time test. It is useful in the diagnosis of
von Willebrand disease (vWD) and other inherited
disorders of platelet function.
• Bleeding time, which measures the interaction
between platelets and the vessel wall. It is
nonspecific and therefore has now been largely
replaced by the PFA.
• Fibrinogen levels, which are usually measured if the
APTT and the PT are deranged, and are altered in
inherited fibrinogen disorders or liver disease.
• Specific factors assay.
• Genetic analysis.
161
Excessive bruising and bleeding
Table26.1 Summary of the common clotting tests in bleeding disorders
Platelet count PT APTT TT
Haemophilia A Normal Normal Prolonged Normal
Haemophilia B Normal Normal Prolonged Normal
vWD Normal Normal Prolonged/normal Normal
DIC Low Prolonged Prolonged Prolonged
Liver disease Low Prolonged Prolonged Prolonged
Warfarin Normal Grossly prolonged Prolonged Normal
Heparin Normal Mildly prolonged Prolonged Prolonged
NOAC Normal Prolonged/normal Prolonged Prolonged/normal
APTT, Activated partial thromboplastin time; DIC, disseminated intravascular coagulation; NOAC, novel oral anticoagulant; PT,
prothrombin time; TT, thrombin time; vWD, von Willebrand disease.
DIFFERENTIAL DIAGNOSIS
The differential diagnosis for bleeding disorders can be
based on a possible underlying abnormality. This can include platelets, coagulation cascade or vessel wall disease.
Platelet abnormality
Thrombocytopenia
This is described as a platelet count below 150 × 109/L. It
can have a variety of causes:
• Reduced production: bone marrow failure (e.g.
myelodysplastic syndrome), drugs (commonly
cytotoxic medication), chemotherapy or radiotherapy,
viral infections (including HIV infection), hereditary
syndromes (e.g. Fanconi anaemia).
• Decreased survival: immune thrombocytopenic
purpura, DIC, thrombotic thrombocytopenic purpura,
haemolytic uraemic syndrome, systemic lupus
erythematosus, HIV and hypersplenism.
• Abnormal distribution: splenic pooling in splenomegaly.
• Dilutional: massive transfusion.
• Factitious: isolated thrombocytopenia
may be related to aggregation caused by
EDTA(Ethylenediaminetetraacetic acid) used in full
blood count bottles.
HINTS AND TIPS
Heparin is the most common drug-related
cause of thrombocytopenia in hospitalized
patients. Heparin-induced thrombocytopenia is a
procoagulant state.
Platelet dysfunction
• Hereditary: Glanzmann thrombasthenia, vWD.
• Acquired: medication (aspirin, heparin, clopidogrel),
chronic kidney disease, myeloproliferative and
myelodysplastic syndromes, multiple myeloma and
paraproteinaemia.
Coagulation abnormality
Coagulopathies may be due to vitamin K deficiency, factor
deficiency (which can be specific or combined, inherited or
acquired) or acquired clotting factor inhibitors.
Vitamin K deficiency
Prothrombin and factor VII, IX and X are dependent on vitamin K. Deficiency may be caused by:
• malabsorption: bowel disease such as coeliac
disease or biliary obstruction (vitamin K is fat
soluble);
• antagonist drugs: coumarins (warfarin).
Factor deficiency
• Hereditary: haemophilia A (factor VIII), haemophilia
B (factor IX), vWD (von Willebrand factor).
• Acquired: liver disease (decreased production of
clotting factors as synthetic function fails), DIC
(massive consumption of clotting factors resulting in
deficiency).
Acquired factor inhibitors
These are most commonly directed against factor VIII:
• postpartum;
• autoimmune disease: systemic lupus erythematosus
and rheumatoid arthritis;
• malignancy.
162
Differential diagnosis
2626
Vessel wall abnormalities
Vessel wall abnormalities may be hereditary or acquired.
Hereditary
• Hereditary haemorrhagic telangiectasia (Osler– Weber–
Rendu disease).
• Connective tissue disease: pseudoxanthoma elasticum,
Ehlers–Danlos syndrome.
Acquired
• Trauma.
• Physiological: senile purpura.
• Drugs: corticosteroids.
• Infections: meningococcal septicaemia (damage due to
endotoxin and inflammation).
• Vitamin deficiency: scurvy (vitamin C).
• Endocrine: Cushing syndrome.
Chapter Summary
• Haemostasis is an important element in maintaining body function.
• Its disorder can come from abnormalities in the coagulation cascade, platelets and their
level or blood vessel walls.
• It can cause severe excessive bruising and bleeding but can also be a symptom of
potentially sinister underlying condition, such as a malignancy.
• History taking and examination should focus on the pattern of bleeding.
• Simple blood tests, including full blood count and coagulation screen, can elucidate the
disease involved, but more specific tests, such as genetic testing, are also available in more
complicated cases.
163
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DIAGNOSES
Chapter 27
Cardiovascular system . . . . . . . . . . . . . . . 167
Chapter 28
Respiratory system. . . . . . . . . . . . . . . . . .201
Chapter 29
Gastrointestinal and hepatobiliary systems . . . . 229
Chapter 30
Renal, genitourinary and sexual health medicine . .253
Chapter 31
Fluid balance and electrolyte disturbances . . . . . 275
Chapter 32
Nervous system . . . . . . . . . . . . . . . . . . .283
Chapter 33
Metabolic and endocrine disorders . . . . . . . . . 305
Chapter 34
Musculoskeletal system . . . . . . . . . . . . . . . 335
Chapter 35
Skin disease . . . . . . . . . . . . . . . . . . . . . 347
Chapter 36
Haematological disorders . . . . . . . . . . . . . . 357
Chapter 37
Infectious diseases . . . . . . . . . . . . . . . . . . 375
Chapter 38
Drug overdose and abuse . . . . . . . . . . . . . . 385
Cardiovascular system
27
CORONARY HEART DISEASE
General overview
Ischaemic heart disease (IHD) is a condition that falls under the umbrella term of ‘cardiovascular disease’ (CVD).
CVD is responsible for almost one-third of all deaths in
the United Kingdom, with IHD being the biggest contributor, accounting for more than 70,000 deaths each year.
The term covers a group of clinical syndromes, including
angina pectoris and acute coronary syndrome (ACS), which
includes ‘unstable angina’, non-ST elevation myocardial infarction (NSTEMI) and ST elevation myocardial infarction
(STEMI). The commonest underlying disease is atherosclerosis of the coronary arteries. More rarely, CVD can result
from coronary artery spasm, emboli, coronary ostial stenosis, aortic stenosis, hypertrophic obstructive cardiomyopathy (HOCM), arrhythmias causing decreased coronary
perfusion pressures and anaemia.
The prevalence of CVD has a geographical variation, reflecting both genetic and lifestyle factors. It is estimated that
1 in 7 men and 1 in 11 women die of CVD each year in the
United Kingdom. Prevalence is highly age dependent and is
highest in those older than 75years.
CLINICAL NOTE
CARDIAC SYNDROME X
Cardiac syndrome X is cardiac ischaemia in the
presence of normal coronary arteries. It is thought
to be due to abnormalities of small coronary
vessels resulting in a reduction of coronary
flow reserve and is therefore also referred to as
‘microvascular angina’.
Risk factors
Multiple factors are involved in the cause of CVD. The
disease results from an interaction of genetic, lifestyle and
environmental factors. A number of risk factors have been
found to be associated with an increased likelihood of developing CVD (Table 27.1). Typically, risk factors are di-
vided into modifiable and nonmodifiable. All modifiable
risk factors should be addressed as part of the assessment in
patients with suspected CVD. Baseline blood pressure (BP)
measurement and measurement of lipid profile and glucose levels should be performed. Smoking cessation advice
should be offered.
Table27.1 Major risk factors for coronary artery disease
Type Risk factors
Nonmodifiable Age
Male sex > female sex
Family history
Ethnicity
Modifiable Smoking
Poor nutrition
Hyperlipidaemia
Hypertension
Diabetes mellitus
Left ventricular hypertrophy
Infrequent exercise
Obesity
Other Social deprivation
Nonmodifiable risk factors
Age
The prevalence of CVD rises steeply with increasing age.
This may be due to the cumulative effects of risk factors
over time.
Sex
CVD is the leading cause of death in both men and women;
however, the rate in young men is higher than in women
of the same age, with 70% of deaths in those younger than
75 years occurring in men. Women develop CVD 10–
15years later in life than men on average, and the greatest
increase in risk of CVD in women occurs after menopause.
It is not clear exactly what feature associated with menopause is associated with this increased risk, and most attention has focused on the role of oestrogen in inflammation.
The difference in risk diminishes with increasing age, and
the rates of the disease are similar in both sexes after the
age of 75years.
Family history
A family history in first-degree relatives increases the risk of
developing CVD. A small proportion of cases are associated
with familial hypercholesterolaemia.
Ethnicity
The prevalence of CVD in British South Asians is high compared with that in their family members remaining on the
Indian subcontinent.
167