Pneumonia

Question 1

What type of organism most commonly causes pneumonia?

Answer 1

Bacteria

Viruses and fungi also cause pneumonia but rarely

Question 2

Which organism accounts for 80% of cases of pneumonia?

Answer 2

Strep. pneumoniae

Community acquired

All treatment and investigation strategies need to cover this

Question 3

Which pneumonia causing organism is especially common in patients with COPD?

Answer 3

H. influenzae

Question 4

Which pneumoniae causing organism is most commonly found in alcoholics?

Answer 4

Klebsiella pneumoniae

Question 5

Which pneumonia-causing organism is typically found in patients with HIV?

Answer 5

Pneumocystis jiroveci

Question 6

What is atypical pneumonia?

Answer 6

AKA walking pneumonia

Pneumonia caused by any organism outside of the usual causes

Examples: mycoplasma pneumoniae and legionella pneumophilia

Question 7

Why is it important to differentiate between community and hopsital acquired pneumonia?

Answer 7

They have different causative organisms and therefore different antibiotics as first line treatments

Question 8

What is the classical x-ray finding in pneumonia?

Answer 8

Consolidation (air is replaced with something else)

Question 9

In whom is community acquired pneumonia most common?

Answer 9

Extremes of ages… think Stan

Question 10

Risk factors for community acquired pneumonia

Answer 10

<16yrs or >65yrs

Co-morbidities e.g. HIV, DM, CKD

Other respiratory conditions

Lifestyle: smoking, IV drug use

Iatrogenic: immunosuppressants

Question 11

Clinical features of community acquired pneumonia

Answer 11

Cough

Breathlessness: alveoli become full of crap and gas exchange is impaired 😰

Fever: if swinging fever present this suggests empyema

Chest pain: commonly pleuritic

Other: in the elderly can present as confusion nor recurrent falls

Question 12

Are bacteria that cause community acquired pneumonia usually gram positive or negative?

Answer 12

Gram positive

Question 13

How is the severity of pneumonia assessed?

Answer 13

CURB 65 score

• Gives a guide to the likely risk of fatal outcome

*CRB-65 is used in the communtiy when the level of urea is not available

Question 14

What does the CURB-65 score encompass?

Answer 14

C = confusion present +1

U = plasma urea >7mmol/L +1

R = respiratory rate >30 +1

B = systolic BP <90 diastolic <60

65 = age 65+

Question 15

Which organisms cause community acquired pneumonia?

Answer 15

1. Strep pneumoniae (most common) 55-75%
2. Mycoplasma pneumoniae 5-18% - epidemics every few years in young people
3. Influenza 8% - usually affects people with underlying lung disease
4. Legionella pneumophila: gram negative, found in cooling towers, causes severe pneumonia with high mortality rates

Question 16

Are hospital acquired pneumonias usually caused by gram positive or negative bacteria?

Answer 16

Gram negative

Question 17

Which pathogens are associated with hospital acquired pneumonia?

Answer 17

1. Pseudomonas aeruginosa (spp = several species)
2. Escherichia spp
3. Klebsiella spp

Question 18

What should be done if community acquired pneumonia is suspected but chest x-ray is clear?

Answer 18

Repeat x-ray in a few days as radiological abnormalities can lag behind clinical signs

Question 19

Discuss blood tests for community acquired pneumonia

Answer 19

• FBC, U&E, biochemistry and CRP

Strep pneumoniae - white cell count very high

Mycoplasma - white cell count usually normal

Question 20

What organism causes rust coloured sputum in pneumonia?

Answer 20

Strep pneumoniae

Question 21

Which organism causes pneumonia in young people and cycles every 3-4yrs?

Answer 21

Mycoplasma pneumoniae