CPC 3 pleural effusion

Question 1

Clinical examination findings suggesting pleural effusion

Answer 1

Dull percussion
Decreased vocal fremitus
Decreased breath sounds
Decreased vocal resonance. 
Asymmetrical decreased chest expansion.

Question 2

Mechanisms for the formation of pleural fluid

Answer 2

Increase hydrostatic
pressure
 Decreased oncotic
pressure
 Increased permeability
of pleura
 Increased pulmonary
interstitial fluid
 Movement from other
cavities (peritoneal)
 Vascular rupture into thorax
 Rupture of thoracic duct

Question 3

Does cardiac failure cause right, left or bilateral pleural effusions?

Answer 3

Any of the above, though equal ones are slightly more common.

Question 4

What are the BTS guidelines for how to manage a pleural effusion?

Answer 4

Take a history, clinical examination and CXR. If a transudative causes is likely from the clinical picture, then treat the cause. If not, or if treatment is unsuccessful, refer to a chest physician.

Question 5

What are Light’s criteria to diagnose exudative pleural fluid?

Answer 5

Pleural fluid is an exudate if one or more of the following
criteria are met:
 Pleural fluid protein divided by serum protein is >0.5
 Pleural fluid lactate dehydrogenase (LDH) divided by
serum LDH is >0.6
 Pleural fluid LDH >2/3 the upper limits of laboratory
normal value for serum LDH.

Question 6

Basic rule of thumb to differentiate an exudative from a transudative pleural fluid.

Answer 6

Pleural fluid protein >30 g/l has indicated an exudate and

Question 7

Common causes of exudative pleural fluid.

Answer 7

Parapneumonic effusions,

Malignancy.

Question 8

Causes of transudative pleural fluid.

Answer 8

All the failures: 
LVF
liver failure (cirrhotic disease), hypoalbuminaemia and peritoneal dialysis. 
nephrotic syndrome
hypothyroidism. 

Also:
PE
mitral stenosis
constrictive pericarditis.

Question 9

If pleural fluid has NT-proBNP level of >1500, what does this mean?

Answer 9

Suggests cause of transudative effusion is cardiac failure.

Question 10

What does a pleural fluid pH

Answer 10

Malignant effusion, pleural infection, connective tissue disorder esp rheumatoid arthritis, TB or oesophageal rupture.

Question 11

If pleural fluid glucose is low what is likely to be the cause?

Answer 11

Infection, arthritis or cancer:
complicated parapneumonic
effusions, empyema, rheumatoid pleuritis and pleural effusions
associated with TB, malignancy and oesophageal rupture

Question 12

Pleural amylase can be useful when?

Answer 12

in suspected cases of oesophageal rupture or effusions associated with pancreatic diseases.

Question 13

Microbiology of community acquired pneumonia

Answer 13

Strep spp are more than half.

The rest are Staph aureus, enterobacteriaceae, or anaerobes.

Question 14

Microbiology of HAP

Answer 14

Staph (25% MRSA)
Gram neg aerobes e.g. E. coli, Pseudomonas and Klebsiella.
Anaerobes.

Question 15

Routes by which bacteria can enter the pleural space.

Answer 15

1) Across the pleura from the adjacent lung.
2) Via visceral pleural defects of fistulae e.g. in cancer, necrotising pneumonia etc.
3) Haematogenous spread
4) Penetrating injury
5) Spread from mediastinum e.g. oesophageal rupture.
6) Across the diaphragm.

Question 16

Neutrophils in pleural fluid suggest what condition?

Answer 16

Underlying pneumonia.

Question 17

Frank pus in pleural fluid suggests what condition?

Answer 17

Empyema

Question 18

What cells in pleural fluid can mimic malignancy?

Answer 18

Reactive mesothelial cells.

Question 19

Eosinophils in pleural fluid suggest what condition?

Answer 19

Pneumothorax or haemothorax. Rarely, drug reactions, parasitic infection, pulmonary infection, or Churg-Strauss syndrome.

Question 20

Lymphocytes in pleural fluid suggest what condition?

Answer 20

Inflammatory disease such as RA,
Infection, including mycobacterial,
Malignancy,
previous CABG.

Question 21

Usual imaging on presentation of mesothelioma.

Answer 21

Nodular or extensive pleural thickening, large unilateral pleural effusion, contraction of affected hemithorax,
invasion of surrounding structures,
focal pleural plaques.

Question 22

CT features of an empyema

Answer 22

 Lenticular shape
 Uniform enhancing wall
 Compression of adjacent lung
 Obtuse angle with chest wall
 ‘Split pleura’-separation of pleural layers
 May have air fluid level

Question 23

Pleural tumours other than malignant mesothelioma

Answer 23

Mesenchymal including sarcoma

Lymphoma

Question 24

Usual presentation of mesothelioma

Answer 24

Chest pain and dyspnoea

Bloody pleural effusion

Question 25

Progress of malignant mesothelioma.

Answer 25

 May be locally invasive (similar to lung
cancer)
 Nodules –> plaques –> encase lung
 Metastasises to nodes and distant sites late

Question 26

Tissue diagnosis of mesothelioma requires…

Answer 26

Targeted needle biopsy or thoracoscopic biopsy

May need repeated attempt to get confirmation

Question 27

Histological types of mesothelioma

Answer 27

 Epithelioid
 Sarcomatoid
 Biphasic
 Desmoplastic

Question 28

Prognosis of mesothelioma.

Answer 28

94% die within 2 years of onset of symptoms
 Median survival 10 months
 Prognosis for epithelioid subtype slightly
better than for sarcomatoid or biphasic types

Question 29

Benign lung tumours

Answer 29

Hamartoma.

Question 30

Definition of hamartoma.

Answer 30

A tumour formed of mature
but disorganised elements normally found at
that site.

Question 31

Key points about a hamartoma.

Answer 31

 Circumscribed peripheral ‘coin’ lesion
 Symptomless, incidental
 Composed of cartilage, epithelium and connective
tissue
 No malignant potential

Question 32

Factors predisposing to lung cancer.

Answer 32

SMOKING!!!
Urban living
Asbestos
Radon gas
Radiotherapy

Question 33

Basic division of lung cancers

Answer 33

Non-small cell
Endocrine
Rarities

Question 34

Types of non-small cell lung cancer.

Answer 34

Adenocarcinoma (common in non-smokers)
Squamous cell carcinoma (nearly half all lung cancers),
Large cell undifferentiated

Question 35

Types of lung endocrine tumour

Answer 35

Small cell (metastasises early). 
Large cell neuroendocrine
Carcinoid (typical and atypical, NOT related to smoking.)

Question 36

What age do people present with carcinoid lung cancers? Which type has a better prognosis.

Answer 36

Mean of 50 yrs.

Typical.

Question 37

Is carcinoid lung cancer common?

Answer 37

No, it makes up less than 1% of lung cancers.

Question 38

Complications of carcinoid lung cancers.

Answer 38

Bronchial obstruction inc distal collapse, bronchiectasis or pneumonia.
Haemoptysis

Question 39

Key points about small cell lung cancer (endocrine)

Answer 39

Approx 16% of lung cancer
 Metastasises early
 Mediastinal lymph nodes often larger than
primary lung tumour

Question 40

Prognosis for small cell lung cancer (endocrine)

Answer 40

Chemotherapy is the main treatment
 Only rarely operable
Prognosis is poor
 Approx 3 months untreated
 1-2 years with chemo

Question 41

Key points of squamous cell carcinoma (non-small cell)

Answer 41

40-50% lung cancer and falling
 Arises on a main or segmental bronchus
 May cavitate
 Often directly invades hilar lymph nodes but
metastasises late

Question 42

Precursor lesion for squamous cell carcinoma.

Answer 42

 squamous metaplasia
 squamous dysplasia
 carcinoma in situ

Question 43

Key points for adenocarcinoma

Answer 43

 20-30% of lung cancer and rising proportion
 Female predilection
 Lung cancer in non-smokers often
adenocarcinoma
 May be central or peripheral

Question 44

Precursor lesions for adenocarcinomas

Answer 44

 Atypical adenomatous hyperplasia

 Adenocarcinoma in situ (‘lepidic’)

Question 45

Key points of large cell carcinoma

Answer 45

Crosses the non-small cell/endocrine divide.
 10-20% lung cancer
 No evidence of squamous or glandular
differentiation
 Variety of subgroups
 Large cell neuroendocrine carcinoma best known
 Usually aggressive tumours

Question 46

Spread of lung cancer: local, lymph and distant

Answer 46

Local: any local structure - if symp chain involved, Pancoast’s. Can also spread to recurrent laryngeal nerve or phrenic nerve.
Lymph: Hilum of lung then mediastinal and supraclavicular. Later, neck and abdominal nodes.
Distant: liver, brain, adrenal, bone, kidney, contralateral lung.

Question 47

Staging of tumours

Answer 47

T = how big, how much invaded, how far from carina?
N = lymphnodes, ipsi or contra.
M = contralateral lung, malignant pleural effusion, distant.