26 - Lower Respiratory Tract Infections

Question 1

What is pneumonia

Answer 1

Pneunoitis + consolidation + exudation due to infection

Question 2

Respiratory symptoms of pneumonia

Answer 2

Cough + Pleural pain, dysponea, tachypnoea

Question 3

Systemic symptoms of pneumonia

Answer 3

Sweating, fevers, rigors, shivers, aches and pains

Question 4

Types of pneumonia

Answer 4

Hospital/community acquired

Atypical/typical

Question 5

Hospital acquired pneumonia bacteria

Answer 5

Gram neg - multi drug resistant
= Pseudomonas Aeruginosa
= Enterobacter
= Klebsiella
= Moraxella catarrhalis

Question 6

When do you get HAP

Answer 6

48-72 hours after being admitted

Question 7

Predesposing factors for HAP

Answer 7

Abnormal conscious state, intubation, ventilation, surgery, immunosuppression

Question 8

Symptoms of CAP

Answer 8

Sudden onset of chills –> Fever –> Pleuritic chest pain+ productive cough

Question 9

Chest X-ray in CAP

Answer 9

Lobar consolidation (due to strep pneumonia)

Question 10

Most likely cause of CAP

Answer 10

S. pneumoniae

ALL GRAM POS

Question 11

CAP Typical pathogens

Answer 11

	Streptococcus pneumoniae – most common
	Haemophilus influenzae
	Moraxella catarrhalis 
	(Staphylococcus aureus post influenza)
	Group A streptococcus (Upper RTI)
•	streptococcus pyogenes
	ONLY GET THIS IN CAP NOT HAP

Question 12

CAP Atypical pathogens

Answer 12

Mycoplasma pneumoniae (15-20%)
Chlamydophilia pneumoniae (5%)
C.psittaci (2-5%)
Legionella pneumophillia (5%)
Coxiella burnetii (1%)
Pneumocystis carinii/PCP <1%

Question 13

Mycoplasma pneumoniae

Answer 13

• Droplet transmission
• Epidemics
• Occurs in the young
• CXR shows patchy bilateral bronchopneumonia
o S. AUREUS causes a bilateral CAVITATING bronchopneumonia

Question 14

Chlamydophila pneumoniae

Answer 14

• Intracellular pathogen

* Implicated as potential pathogen / co-pathogen in coronary artery disease and cerebrovascular disease

Question 15

C.psittaci

Answer 15

• Zoonosis acquired from birds

Question 16

Legionella Pneumophilia

Answer 16

• Preferred habitat – WARM WATER
• Large outbreaks associated with cooling towers/spas/air cond.
• History – exposure to cooling towers

Question 17

Clinical features of Legionella pneumophilia

Answer 17

multi-system disease with confusion, muscle aches, pneumonia, renal failure, liver involvement + diarrhoea

Question 18

Lab features of legionella pneumophilia

Answer 18

o CXR - Patchy interstitial involvement or consolidation
o Hyponatraemia often present
o Urea frequently raised
o Liver function tests abnormal

Question 19

Coxiella burnetii

Answer 19

• Causes Q FEVER

* Transmitted via infected animals through milk, excreta

Question 20

 Pneumocystis carinii/PCP

Answer 20

• Important cause of pneumonia in the severely immunocompromised ie HIV
• Presents with non productive cough
• Treat with co trimoxazole or pentamidine by slow iv for 2-3 weeks

Question 21

What is atypical pneumonia

Answer 21

Pneumonia not due to sprep pneumoniae
Doesn’t respond to conventional b-lactam therapy
More insidious
Difficult to culture
= Non-productive cough, fever, headache, chest x-ray more abnormal than suggested by clinical examination
 inflammation restricted to alveolar septa and interstitial tissues - essentially interstitial pneumonitis
 bilateral - patchy CXR
 typical- unilateral

Question 22

Complications of pneumonia

Answer 22

Pleural effusion
Empyema thoracis
Lung abcess
= Single - psudomonas
= Multiple - staphylococcus aureus

Question 23

Diagnosing pneumonia

Answer 23

Hx + clinical
Chest examination
Sputum
Serodiagnosis

Question 24

How to determine severity of pneumonia

Answer 24

CURB 65 score

Question 25

What does CURB 65 stand for

Answer 25

``` C - confusion U - urea >7mmol R - resp rate >30 B - BP <90mmhg 65 - age >65 ```

Question 26

Treatment of mild, moderate, severe pneumonia

Answer 26

o Mild – amoxicillin o Moderate – add clarithromycin o Severe – as above + co-amoxiclav

Question 27

Treatment of HAP

Answer 27

Tazocin

Question 28

Treatment of pneumonia due to Legionella

Answer 28

fluoroquinolone

Question 29

Tx pneumonia due to chlamydophila

Answer 29

tetracycline

Question 30

Tx of pneumonia due to PCP

Answer 30

High dose co-trimoxazole