Saturday, October 20, 2012

CASE 4: SHORTNESS OF BREATH


History
A 26-year-old teacher has consulted her general practitioner (GP) for her persistent cough.
She wants to have a second course of antibiotics because an initial course of amoxicillin
made no difference. The cough has troubled her for 3 months since she moved to a new
school. The cough is now disturbing her sleep and making her tired during the day. She
teaches games, and the cough is troublesome when going out to the playground and on
jogging. In her medical history she had her appendix removed 3 years ago. She had her
tonsils removed as a child and was said to have recurrent episodes of bronchitis between
the ages of 3 and 6 years. She has never smoked and takes no medication other than an
oral contraceptive. Her parents are alive and well and she has two brothers, one of whom
has hayfever.

Examination
The respiratory rate is 18/min. Her chest is clear and there are no abnormalities in the nose,
pharynx, cardiovascular, respiratory or nervous systems.

INVESTIGATIONS
• Chest X-ray is reported as normal.
• Spirometry is carried out at the surgery and she is asked to record her peak flow rate at
home, the best of three readings every morning and every evening for 2 weeks.
Spirometry results are as follows:
Actual Predicted
FEV1 (L) 3.9 3.6–4.2
FVC (L) 5.0 4.5–5.4
FER (FEV1/FVC) (%) 78 75–80
PEF (L/min) 470 440–540
FEV1: forced expiratory volume in 1 s; FVC, forced vital capacity; FER, forced expira-
tory ratio; PEF, peak expiratory flow.

Questions
• What is your interpretation of these findings?
• What do you think is the likely diagnosis and what would be appropriate treatment?

ANSWER 4
The peak flow pattern shows a degree of diurnal variation. This does not reach the diag-
nostic criteria for asthma but it is suspicious. The mean daily variation in peak flow from
the recordings is 36 L/min and the mean evening peak flow is 453 L/min, giving a mean
diurnal variation of 8 per cent. There is a small diurnal variation in normals and a vari-
ation of 15 per cent is diagnostic of asthma. In this patient the label of ‘bronchitis’ as a
child was probably asthma. The family history of an atopic condition (hayfever in a
brother), and the triggering of the cough by exercise and going out in to the cold also sug-
gest bronchial hyper-responsiveness typical of asthma.

Patients with a chronic persistent cough of unexplained cause should have a chest X-ray.
When the X-ray is clear the cough is likely to be produced by one of three main causes in
non-smokers. Around half of such cases have asthma or will go on to develop asthma over
the next few years. Half of the rest have rhinitis or sinusitis with a post-nasal drip. In around
20 per cent the cough is related to gastro-oesophageal reflux. A small number of cases will
be caused by otherwise unsuspected problems such as foreign bodies, bronchial ‘adenoma’,
sarcoidosis or fibrosing alveolitis. Cough is a common side-effect in patients treated with
angiotensin-converting-enzyme (ACE) inhibitors.

In this patient the diagnosis of asthma was confirmed with an exercise test which was
associated with a 25 per cent drop in peak flow after completion of 6 min vigorous exer-
cise. Alternatives would have been another non-specific challenge such as methacholine
or histamine, or a therapeutic trial of inhaled steroids.

After the exercise test, an inhaled steroid was given and the cough settled after 1 week.
The inhaled steroid was discontinued after 4 weeks and replaced by a 2-agonist to use
before exercise. However, the cough recurred with more evident wheeze and shortness of
breath, and treatment was changed back to an inhaled steroid with a  2-agonist as
needed. If control was not established, the next step would be to check inhaler technique
and treatment adherence and to consider adding a long-acting 2-agonist. In some cases,
the persistent dry cough associated with asthma may require more vigorous treatment
than this. Inhaled steroids for a month or more, or even a 2-week course of oral steroids
may be needed to relieve the cough. The successful management of dry cough relies on
establishing the correct diagnosis and treating it vigorously.


Monday, October 15, 2012

CASE 3: CHRONIC COUGH


History
A 19-year-old boy has a history of repeated chest infections. He had problems with a cough
and sputum production in the first 2 years of life and was labelled as bronchitic. Over the next
14 years he was often ‘chesty’ and had spent 4–5 weeks a year away from school. Over the past
2 years he has developed more problems and was admitted to hospital on three occasions with
cough and purulent sputum. On the first two occasions, Haemophilus influenzae was grown
on culture of the sputum, and on the last occasion 2 months previously Pseudomonas aerugi-
nosa was isolated from the sputum at the time of admission to hospital. He is still coughing up
sputum. Although he has largely recovered from the infection, his mother is worried and asked
for a further sputum to be sent off. The report has come back from the microbiology labora-
tory showing that there is a scanty growth of Pseudomonas on culture of the sputum.
There is no family history of any chest disease. Routine questioning shows that his appetite
is reasonable, micturition is normal and his bowels tend to be irregular.
 
Examination
On examination he is thin, weighing 48 kg and 1.6m (5 ft 6 in) tall.
• The only finding in the chest is of a few inspiratory crackles over the upper zones of
both lungs. Cardiovascular and abdominal examination is normal.

Questions
• What does the X-ray show?
• What is the most likely diagnosis?
• What investigations should be performed?

ANSWER 3
The chest X-ray shows abnormal shadowing throughout both lungs, more marked in both
upper lobes with some ring shadows and tubular shadows representing thickened bronchial
walls. These findings would be compatible with a diagnosis of bronchiectasis. The pul-
monary arteries are prominent, suggesting a degree of pulmonary hypertension. The distri-
bution is typical of that found in cystic fibrosis where the changes are most evident in the
upper lobes. Most other forms of bronchiectasis are more likely to occur in the lower lobes
where drainage by gravity is less effective. High-resolution computed tomography (CT) of
the lungs is the best way to diagnose bronchiectasis and to define its extent and distribu-
tion. In younger and milder cases of cystic fibrosis, the predominant organisms in the spu-
tum are Haemophilus influenzae and Staphylococcus aureus. Later, as more lung damage
occurs, Pseudomonas aeruginosa is a common pathogen. Once present in the lungs in cys-
tic fibrosis, it is difficult or impossible to remove it completely.

Cystic fibrosis should always be considered when there is a story of repeated chest infec-
tions in a young person. Although it presents most often below the age of 20 years, diag-
nosis may be delayed until the 20s, 30s or even 40s in milder cases. Associated problems
occur in the pancreas (malabsorption, diabetes), sinuses and liver. It has become evident
that some patients are affected more mildly, especially those with the less common genetic
variants. These milder cases may only be affected by the chest problems of cystic fibrosis
and have little or no malabsorption from the pancreatic insufficiency.

!
The differential diagnosis in this young man would be other causes of diffuse
bronchiectasis such as agammaglobulinaemia or immotile cilia. Respiratory function
should be measured to see the degree of functional impairment. Bronchiectasis in the
upper lobes may occur in tuberculosis or in allergic bronchopulmonary aspergillosis
associated with asthma.

The common diagnostic test for cystic fibrosis is to measure the electrolytes in the sweat,
where there is an abnormally high concentration of sodium and chloride. At the age of
19 years, the sweat test may be less reliable. It is more specific if repeated after the adminis-
tration of fludrocortisone. An alternative would be to have the potential difference across
the nasal epithelium measured at a centre with a special interest in cystic fibrosis. Cystic
fibrosis has an autosomal recessive inheritance with the commonest genetic abnormality
F508 found in 85 per cent of cases. The gene is responsible for the protein controlling
chloride transport across the cell membrane. The commoner genetic abnormalities can be
identified and the current battery of genetic tests identifies well over 95 per cent of cases.
However, the absence of F508 and other common abnormalities would not rule out cys-
tic fibrosis related to the less common genetic variants.
In later stages, lung transplantation can be considered. Since the identification of the
genetic abnormality, trials of gene-replacement therapy have begun.

Friday, October 12, 2012

CASE 2: CHEST PAIN


History
A 34-year-old male accountant comes to the emergency department with acute chest
pain. There is a previous history of occasional stabbing chest pain for 2 years. The current
pain had come on 4 h earlier at 8 pm and has been persistent since then. It is central in
position, with some radiation to both sides of the chest. It is not associated with shortness
of breath or palpitations. The pain is relieved by sitting up and leaning forward. Two
paracetamol tablets taken earlier at 9 pm did not make any difference to the pain.
The previous chest pain had been occasional, lasting a second or two at a time and with
no particular precipitating factors. It has usually been on the left side of the chest
although the position had varied.
Two weeks previously he had an upper respiratory tract infection which lasted 4 days. This
consisted of a sore throat, blocked nose, sneezing and a cough. His wife and two children
were ill at the same time with similar symptoms but have been well since then. He has a his-
tory of migraine. In the family history his father had a myocardial infarction at the age of
51 years and was found to have a marginally high cholesterol level. His mother and two sis-
ters, aged 36 and 38 years, are well. After his father’s infarct he had his lipids measured; the
cholesterol was 5.1mmol/L (desirable range 5.5mmol/L). He is a non-smoker who drinks
15 units of alcohol per week.

Examination
His pulse rate is 75/min, blood pressure 124/78mmHg. His temperature is 37.8°C. There is
nothing abnormal to find in the cardiovascular and respiratory systems.

INVESTIGATIONS
A chest X-ray is normal. The haemoglobin and white cell count are normal. The creatine
kinase level is slightly raised. Other biochemical tests are normal.

Questions
• What is the diagnosis?
• Should thrombolysis be given?

ANSWER 2
The previous chest pains lasting a second or two are unlikely to be of any real signifi-
cance. Cardiac pain, and virtually any other significant pain, lasts longer than this, and
stabbing momentary left-sided chest pains are quite common. The positive family history
increases the risk of ischaemic heart disease but there are no other risk factors evident
from the history and examination. The relief from sitting up and leaning forward is typical
of pain originating in the pericardium. The ECG shows elevation of the ST segment which
is concave upwards, typical of pericarditis and unlike the upward convexity found in the
ST elevation after myocardial infarction.
The story of an upper respiratory tract infection shortly before suggests that this may well
have a viral aetiology. The viruses commonly involved in pericarditis are Coxsackie B
viruses. The absence of a pericardial rub does not rule out pericarditis. Rubs often vary in
intensity and may not always be audible. If this diagnosis was suspected, it is often worth
listening again on a number of occasions for the rub. Pericarditis often involves some adja-
cent myocardial inflammation and this could explain the rise in creatine kinase.
Pericarditis may occur as a complication of a myocardial infarction but this tends to occur
a day or more later – either inflammation as a direct result of death of the underlying heart
muscle, or as a later immunological effect (Dressler’s syndrome). Pericarditis also occurs
as part of various connective tissue disorders, arteritides, tuberculosis and involvement
from other local infections or tumours. Myocardial infarction is not common at the age of
34 years but it certainly occurs. Other causes of chest pain, such as oesophageal pain or
musculoskeletal pain, are not suggested by the history and investigations.
Thrombolysis in the presence of pericarditis carries a slight risk of bleeding into the peri-
cardial space, which could produce cardiac tamponade. This arises when a fluid (an effu-
sion, blood or pus) in the pericardial space compresses the heart, producing a paradoxical
pulse with pressure dropping on inspiration, jugular venous pressure rising on inspiration
and a falling blood pressure. In this case, the evidence suggests pericarditis and thrombol-
ysis is not indicated. The ECG and enzymes should be followed, the patient re-examined
regularly for signs of tamponade, and analgesics given.

A subsequent rise in antibody titres against Coxsackie virus suggested a viral pericarditis.
Symptoms and ECG changes resolved in 4–5 days. An echocardiogram did not suggest any
pericardial fluid and showed good left ventricular muscle function. The symptoms settled
with rest and non-steroidal anti-inflammatory drugs.

Tuesday, October 9, 2012

case1 dizziness

CASE 1: DIZZINESS

History
A 75-year-old man is brought to hospital with an episode of dizziness. He still feels unwell
when he is seen 30 min after the onset. He was well until the last 6 months, since when
he has had some falls, irregularly. On some occasions he lost consciousness and is unsure
how long he has been unconscious. On a few occasions he has fallen, grazing his knees,
and on others he has felt dizzy and has had to sit down but has not lost consciousness.
These episodes usually happened on exertion, but once or twice they have occurred while
sitting down. He recovers over 10–15 min after each episode.

He lives alone and most of the episodes have not been witnessed. Once his granddaughter
was with him when he blacked out. Worried, she called an ambulance. He looked so pale
and still that she thought that he had died. He was taken to hospital, by which time he had
recovered completely and was discharged and told that he had a normal electrocardiogram
(ECG) and chest X-ray.

There is no history of chest pain or palpitations. He has had gout and some urinary fre-
quency. A diagnosis of benign prostatic hypertrophy has been made for which he is on no
treatment. He takes ibuprofen occasionally for the gout. He stopped smoking 5 years ago.
He drinks 5–10 units of alcohol weekly. The dizziness and blackouts have not been asso-
ciated with alcohol. There is no relevant family history. He used to work as an electrician.

Examination
He is pale with a blood pressure of 96/64mmHg. The pulse rate is 33/min, regular. There
are no heart murmurs. The jugular venous pressure is raised 3 cm with occasional rises.
There is no leg oedema; the peripheral pulses are palpable except for the left dorsalis pedis.
The respiratory system is normal.

INVESTIGATIONS
Questions
• What is the cause of his blackout?
• What does the ECG show?

ANSWER 1
The blackouts do not seem to have had any relationship to posture. They have been a mix-
ture of dizziness and loss of consciousness. The one witnessed episode seems to have been
associated with loss of colour. This suggests a loss of cardiac output usually associated with
an arrhythmia. This may be the case despite the absence of any other cardiac symptoms.
There may be an obvious flushing of the skin as cardiac output and blood flow return.
The normal ECG and chest X-ray when he attended hospital after an episode do not rule out
an intermittent conduction problem. On this occasion the symptoms have remained in a
more minor form. The ECG shows third-degree or complete heart block. There is complete
dissociation of the atrial rate and the ventricular rate which is 33/min. The episodes of loss
of consciousness are called Stokes–Adams attacks and are caused by self-limited rapid tachy-
arrhythmias at the onset of heart block or transient asystole. Although these have been
intermittent in the past he is now in stable complete heart block and, if this continues, the
slow ventricular rate will be associated with reduced cardiac output which may cause
fatigue, dizziness on exertion or heart failure. Intermittent failure of the escape rhythm may
cause syncope.

On examination, the occasional rises in the jugular venous pressure are intermittent ‘can-
non’ a-waves as the right atrium contracts against a closed tricuspid valve. In addition,
the intensity of the first heart sound will vary.

!
The differential diagnosis
of transient loss of consciousness splits into neurological
and vascular causes. A witness is very helpful in differentiation. Neurological causes
are various forms of epilepsy, often with associated features. Vascular causes are
related to local or general reduction in cerebral blood flow. Local reduction may
occur in transient ischaemic attacks or vertebrobasilar insufficiency. A more global
reduction, often with pallor, occurs with arrhythmias, postural hypotension and
vasovagal faints.

The treatment should be insertion of a pacemaker. If the rhythm in complete heart block
is stable then a permanent pacemaker should be inserted as soon as this can be arranged.
This should be a dual-chamber system pacing the atria then the ventricles (DDD, dual
sensing and pacing, triggered by atrial sensing, inhibited by ventricular sensing) or pos-
sibly a ventricular pacing system (VVI, pacing the ventricle, inhibited by ventricular sens-
ing). If there is doubt about the ventricular escape rhythm then a temporary pacemaker
should be inserted immediately.