Pneumonia

Question 1

What is the most common bacterial cause of lobar pneumonia?

Answer 1

Streptococcus pneumonia

Other organisms - klebsiella and legionella

Question 2

What is the definition of lobar pneumonia?

Answer 2

Confluent consolidation involving a complete lung lobe

Question 3

What is the standard test for confirming suspicion of legionella infection?

Answer 3

Urine antigen testing

Question 4

What is the most useful antibiotic for clearing legionella infection?

Answer 4

Macrolides - erythromycin, clarithromycin, azithromycin
These inhibit protein synthesis in bacteria by binding to ribosome and stopping formation of peptide bonds. They are useful in legionella as they can cross cell membranes easily - they are lipophilic.
Using CURB65/ SIGN guidelines - add levofloxacin to standard treatment in moderate - severe cases

Question 5

Describe the inflammatory response involved.

Answer 5

Classical acute inflammatory response - exudation of fibrin rich fluid including neutrophil and macrophage infiltration.

Question 6

Name some of the complications of pneumonia.

Answer 6

Fibrous scarring
Bronchiectasis
Abscess
Empyema
Pleural effusion
Respiratory failure
Death

Question 7

Describe bronchopneumonia.

Answer 7

Infection starting in airways and spreading to adjacent alveolar tissue

Question 8

What investigations should be done if a diagnosis of pneumonia is suspected?

Answer 8

Blood culture
Serology
FBC
U&Es
LFTs
CXR
Arterial gases

Question 9

Describe the CURB65 scoring system.

Answer 9

C - confusion
U - urea >7
R - respiratory rate > 30
B - blood pressure  65
Score 1 point for each of these.

Question 10

Using the CURB65 system, how many points does each level of severity merit?

Answer 10

0 = low severity.
1/2 = moderate severity
3/4 = high severity. This requires urgent hospital admission.

Question 11

What is the standard treatment for low severity pneumonia?

Answer 11

Amoxicillin 500mg
OR
Doxycycline 200mg & clarithromycin 500mg

Question 12

What is the standard treatment for high severity pneumonia?

Answer 12

Co-amoxiclav & clarithromycin
Add levofloxacin for legionella
OR
Benzylpenicillin & ciprofloxin

Question 13

Which organism should be considered in an immunosuppressed patient?

Answer 13

Pneumocystis carinii is a fungus which causes pneumocystis pneumonia (PCP) in immunosuppressed patients. This tends to present with dry cough, SOB and pulmonary infiltrates on CXR.

Question 14

Which is the most common cause of community acquired pneumonia?

Answer 14

Pneumococcus/strep. pneumoniae
Other organisms - 
Haemophilus influenza
Klebsiella pneumonia (think alcoholics)
Group A streptococcus

Question 15

What type of organisms tend to cause hospital acquired pneumonia?

Answer 15

Gram negative

Also - staph. aureus

Question 16

Which organism can cause additional respiratory tract infection in those with influenza?

Answer 16

Staph. aureus

Question 17

Which antibiotic can be given initially to cover the possibility of atypical organisms such as mycoplasma pneumoniae?

Answer 17

Erythromycin

Question 18

Which is the best antibiotic for pneumococcal pneumoniae?

Answer 18

Penecillin i.e. amoxicillin

Question 19

What does a persistent swinging fever indicate?

Answer 19

May indicate that empyema has developed. This should prompt further examination and repeat CXR.

Question 20

Other than those indicated on the CURB65 score, what are other indicators of severe pneumonia?

Answer 20

Temperature - 40

Cyanosis - PaO2 30

Question 21

Describe strep. pneumoniae.

Answer 21

Gram-positive cocci in pairs or short chains

Alpha haemolytic

Question 22

How should severe nosocomial pneumonia be treated?

Answer 22

IV amoxicillin & gentamicin & metronidazole

Question 23

What are the main risk factors for developing community acquired pneumonia?

Answer 23

Winter months 
The very young and the very old 
Chronic lung, heart, renal and liver disease
Diabetes mellitus 
Immunosuppression

Question 24

In which patients in bronchopneumonia most common?

Answer 24

In patients with pre-existing disease

Question 25

What bacteria should be considered the cause of pneumonia in alcoholics?

Answer 25

Klebsiella