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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3120_Библиотеки_им_академика_М_И_Перельмана
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Case 69: Bruising after a Pneumonia
199
KEY POINTS
•
Any change in the patient’s condition needs to be discussed with senior col-
leagues prior to discharge.
•
Significant bruising needs to be investigated before reassuring the patient that
there is nothing wrong.
•
Acquired haemophilia A is a disorder of antibodies against factor VIII.
•
Treatment is immune suppression, with a bypassing agent to stop any bleeding.
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CASE 70: HEADACHE AND A RASH
A 34-year-old woman presents to the emergency department with a headache. She saw her
GP last week, who thought her symptoms may stem from stress at work. The headache is get-
ting worse and is not responding to analgesia. She has no vomiting, and her headache feels
like a band around her head. It was not made worse by lying flat or by straining. She also
complains of coryzal symptoms. She has no significant past medical history.
Examination
She has no skin rash and her observations are all normal. Respiratory and cardiovascular
examinations are both normal. Gross neurological assessments, including her reflexes, are
normal. She has no photophobia. The doctors arrange routine blood tests.
While waiting for the results, she develops a high temperature of 39.4°C, and the nurse
reports to the doctors that the patient has noticed a skin rash.
The doctor returns to reassess the patient, and he notices that she has become slightly vaguer
about her history. On examination, she has developed a small purpuric rash over both her arms.
INVESTIGATIONS
Haemoglobin 82
White cell count 20.1
Neutrophils 15.1
Lymphocytes 3.0
Platelets 17
Reticulocytes 3.1%
Mean corpuscular volume 75
Sodium 136
Potassium 4.0
Urea 5.0
Creatinine 70
Lactate dehydrogenase 1000
Haptoglobins Undetectable
C-reactive protein 70
Blood film shows thrombocytopenia and increased red cell fragments (
Figure 70.1).
QUESTIONS
1. What is the most likely diagnosis?
2. What test would you arrange to confirm the diagnosis?
3. What is your management plan?
DOI: 10.1201/9781003242697-73
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100 Cases in Clinical Pathology and Laboratory Medicine
202
ANSWERS
The patient has anaemia with a high reticulocyte percentage, raised LDH and undetectable
haptoglobins, which suggests haemolysis. Haptoglobins are produced by the liver, and they
are usually consumed by binding to free haemoglobin in the circulation.
Thrombocytopenia is confirmed on the blood film, which also shows increased red blood
cell fragments (Figure 70.1). This is suggestive of microangiopathic haemolytic anaemia
(MAHA), where the red cells are destroyed intravascularly by a mechanical force.
The presence of MAHA, thrombocytopenia, and the development of purpura with neu-
rological symptoms are all features of thrombotic thrombocytopenic purpura (TTP). The
other important dierential diagnosis would be haemolytic uraemic syndrome (HUS), which
in its typical type is associated with diarrhoea and renal failure.
The understanding of the pathophysiology of TTP has improved following the discovery
of the role of ADAMTS-13, which is the 13th member of a family of metalloproteases. The
function of this protease is to regulate the size of the von Willebrand (V W) factor molecule
by cleaving the ultra-large polymers of VW factor once they are released into circulation. A
deficiency in ADAMTS-13 leaves high numbers of large polymers of VW factor in circula-
tion. These polymers are prothrombotic: they adhere to vessel walls in the microcirculation
of many organs and activate passing platelets, leading to widespread platelet-rich thrombi
formation.
Figure 70.1 Blood film showing thrombocytopenia and increased red cell fragments.
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Case 70: Headache and a Rash
203
TTP has congenital and acquired forms. The congenital form usually presents at birth and
is due to an inherited deficiency of ADAMTS-13. The acquired form is secondary to either
autoantibodies against ADAMTS-13, which leads to low levels of the enzyme, or massive
endothelial activation releasing high numbers of the large-size VW factor molecules that
exceeds the ability of the normal levels of the enzyme to regulate them.
Measurement of ADAMTS-13 serum levels would establish the diagnosis of TTP, which is a
medical emergency and has a high mortality rate of 80–90%.
Plasma exchange is the treatment of choice, and it needs to be started as soon as possible. It
should not be delayed until serum ADAMTS-13 results are known.
Plasma exchange is usually done at renal units or at specialist haematology units. If the hos-
pital where the patient has presented does not have such facilities, then plasma infusion can
be started until the patient is transferred. Fresh frozen plasma (FFP) should be given at a high
dose; this would provide a source of functional ADAMTS-13.
KEY POINTS
•
TTP is a medical emergency which can lead to rapid deterioration of a patient.
•
Deficiency in the enzyme ADAMTS-13 or widespread endothelial activation which
exceeds its levels to regulate the size of VW factor polymers leads to widespread
platelet activation and thrombi formation in various organs.
•
Plasma exchange needs to be started promptly, and if not available, plasma infu-
sion should be started.
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CASE 71: SHORTNESS OF BREATH AND
WEIGHT LOSS
A 53-year-old woman presents to her local hospital with shortness of breath. This started
yesterday after she got back home from the school where she works as a dinner lady. She has
not been coughing and has no pain in her chest. She has osteoarthritis in her wrists, for which
she takes non-steroidal anti-inflammatory drugs (NSAIDs). She also reports some symptoms
of lethargy and weight loss over the last 6 months. Occasionally she experiences sweating
at night.
Examination
Her oxygen saturation is 85% on room air and 96% on 5 litres of oxygen. Her temperature is
36.5°C. She has a respiratory rate of 22 and pulse of 110. Auscultation reveals normal heart
sounds and a clear chest. Her abdominal examination reveals no organomegaly. Of note, she
has palpable lymph nodes in the cervical, axillary and inguinal areas.
INVESTIGATIONS
Chest radiograph is reported as normal. The emergency department team requests a
CT pulmonary angiogram (CTPA), which confirms a pulmonary embolus and enlarged
anterior mediastinal, pre-tracheal, hilar, para-aortic and axillary lymph nodes.
QUESTIONS
1.
What immediate action needs to be taken based on these investigations?
2. What further investigations need to be arranged to further assess the other
abnormality in the CTPA report?
3. Who else needs to get involved in the management of this patient?
4. What needs to be taken into account when treating this patient, given her initial
presentation?
DOI: 10.1201/9781003242697-74
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100 Cases in Clinical Pathology and Laboratory Medicine
206
ANSWERS
The patient has hypoxia, tachycardia, and tachypnoea, which is a typical presentation of
pulmonary embolism (PE). Based on these signs, low-molecular-weight heparin (LMWH)
should be started whilst waiting for results of the investigations to confirm or exclude the
PE—either CTPA or V/Q scan.
In provoked cases of PE, anticoagulation treatment should be continued for 3–6 months.
Typically, it starts in the form of an LMWH, followed by oral anticoagulation. Historically,
warfarin was the oral agent of choice. However, now direct oral anticoagulants (DOACs) can
be used with similar eectiveness but no need for monitoring; options include rivaroxaban
and apixaban. For patients started on warfarin, the target therapeutic INR is 2–3, and there
needs to be a bridging period of around 48 hours when both LMWH and warfarin are used,
as the onset of action of warfarin is 36–48 hours.
Many conditions are discovered as incidental findings. This patient presented with a medical
emergency, but this should not distract the team from the fact that another pathology may
have contributed to developing a PE.
The patient has a history of B-symptoms, including night sweats, significant weight loss
(equivalent to around 10% body weight loss over 6 months) and lethargy.
In view of this history and the fact that the patient has enlarged lymph nodes, the top two
dierential diagnoses are lymphoma and tuberculosis (TB). Both conditions are associated
with B-symptoms. However, malignancies increase the risk of developing a PE, which makes
lymphoma the most likely diagnosis here. The most definitive way to confirm the diagnosis
is to do a biopsy of the suspected lesion. For mediastinal lesions, cardiothoracic surgeons can
perform a mediastinoscopy with a biopsy.
While waiting for the biopsy to happen, a few other investigations need to happen:
•
LDH, indicating the degree of cell proliferation
•
Viral screening to exclude hepatitis A, B and C and HIV infection
•
Mantoux test, to screen for TB
•
CT scan of chest, abdomen, and pelvis. This is called a staging CT, and its function
is to exclude further lesions or lymphadenopathy. If the patient has lymph nodes in
the neck, then the CT needs to include the neck in the staging
This patient should be referred to the haematology team, and the case should be discussed in the
multi-disciplinary team meeting to confirm the diagnosis and decide on the management plan.
KEY POINTS
•
Lymphoma can present as an incidental finding, and all suspected patients need
to be screened for the presence of B-symptoms.
•
Verbal reports of imaging need to be followed by formal approved reports to
ensure no pathology is missed.
•
Tissue biopsy is the only test that would confirm the diagnosis of a suspected
lymphoma.
•
Multi-disciplinary team meetings are essential in the management of patients
with malignancies. Unnecessary delays usually happen in the diagnosis process
because of some staging/screening tests not being done.
•
Referral teams need to arrange such tests while awaiting reviews by the specialists.
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CASE 72: ANAEMIA RESISTANT TO A BLOOD
TRANSFUSION
A 32-year-old woman presents to the emergency department with dizziness and headaches.
She had a fainting episode the day before at the school where she works as a teaching assis-
tant. She also reports that her periods have been quite heavy lately. She has no significant
past medical history, and she is not on any regular medications.
Examination
She appears pale and has a tachycardia of 120 bpm. Her BP was 80/55, and her oxygen
saturation is 94%. Abdominal examination reveals splenomegaly. Examination of her heart
sounds and lungs is unremarkable.
INVESTIGATIONS
Haemoglobin 62
White cell count 4.5
Neutrophils 2.1
Lymphocytes 2.0
Platelets 1000
Reticulocytes 6.1%
Mean corpuscular volume 110
Serum iron 20
Total iron binding capacity 50
Transferrin saturation 30%
Bilirubin 90
Aspartate aminotransferase 55
Alkaline phosphatase 100
C-reactive protein 15
Normal levels of urea and electrolytes, B
12
and folate.
She was prescribed 2 units of packed red cells for transfusion. The following
morning she had a post-transfusion blood test:
Haemoglobin 64
Mean corpuscular volume 110
White cell count 4.9
Neutrophils 2.0
Lymphocytes 2.0
Platelets 1100
QUESTIONS
1. What is the most likely diagnosis?
2. How would you explain the post-transfusion blood results?
3. What further tests would you arrange to confirm your diagnosis?
4. What is your management plan?
DOI: 10.1201/9781003242697-75
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100 Cases in Clinical Pathology and Laboratory Medicine
208
ANSWERS
This patient has symptoms and signs consistent with anaemia. She has menorrhagia, which could
cause iron-deficiency anaemia, but her pre-transfusion blood tests showed a macrocytic anaemia.
Iron deficiency would cause microcytic anaemia with a low mean cell volume (MCV). This is not
a combined microcytic and macrocytic anaemia, as her folate and B
12
levels are normal.
The blood film shows polychromasia (Figure 72.1). This is a result of excessive reticulocytes,
which are the cells that precede mature red cells in the maturation stages. They are larger in
size, which explains the raised MCV, and are found in peripheral circulation, usually only
when the bone marrow is under stress to produce more red cells. Nucleated red cells are
another type of cell that are usually found only in the bone marrow, and their presence con-
firms that the bone marrow is under stress. The blood film shows no features of hypochromic
cells typical of iron deficiency.
Bleeding, inflammation, or haemolysis may explain her thrombocytosis. The isolated raised
bilirubin in addition to all of the earlier findings is supportive of haemolysis as the explana-
tion of anaemia.
The emergency department doctor rushed to give a blood transfusion without comprehen-
sively reviewing the results. This is a common problem in busy departments where doctors
are expected to make decisions quickly. The diagnosis in this patient is haemolysis, and giv-
ing a blood transfusion to such patients would not correct the pathology. It is likely that the
two units of transfusion that were given overnight were simply consumed by the haemolytic
process; hence the patient’s haemoglobin levels remained the same.
Figure 72.1 Blood film showing polychromasia, thrombocytosis and some nucleated red
cells.
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