LRTI and Pneumonias

Question 1

What common microbiota are found in the respiratory tract?

Answer 1

Viridans streptococci, Neisseria species, Candida species

Question 2

What defences does the respiratory tract have against pathogens?

Answer 2

Mucociliary clearance mechanisms,
Cough and sneeze reflex,
Respiratory mucosal secretion of IgA and IgG,
Alveolar commensal microorganisms.

Question 3

What virulence factors are presented by mycoplasma pneumoniae?

Answer 3

Shear off cilia to prevent action of the mucociliary elevator

Question 4

What virulence factors allow streptococcus pneumoniae and neisseria meningitides to colonise the lower respiratory tract?

Answer 4

Able to split IgA and as such impair the mucosal immune response.

Question 5

What risk factors are common for lower respiratory tract infections?

Answer 5

Smoking,
Age >65,
Chronic lung disease eg COPD,
Cystic fibrosis,
Aspiration.

Question 6

What drugs may increase the risk of lower respiratory tract infection?

Answer 6

PPI - pneumonia,
H2 antagonists - myelosuporession,
Antipsychotics,
Glucocorticoids.

Question 7

What are the most common causes of acute bronchitis?

Answer 7

Viruses,
Streptococcus pneumoniae,
Haemophilus influenzae.

Question 8

How is acute bronchitis treated?

Answer 8

Bronchodilators and physiotherapist +- antibiotics.

Question 9

What is the difference between lobar pneumonia and bronchopneumonia?

Answer 9

Lobar pneumonia affects an entire lobe, whereas bronchopneumonia shows diffuse patches of damage to the lung.

Question 10

What are the most common causative organisms of typical pneumonia?

Answer 10

Streptococcus pneumoniae,
Haemophilus influenzae,
Viruses such as RSV and Rhinovirus.

Question 11

What are the most common causative organisms of atypical pneumonia?
What are the associations common in the presenting patients history?

Answer 11

Mycoplasma (crowded places such as prisons or boarding schools),
Legionella (contaminated water).

Question 12

What might be heard on auscultation and percussion of chest in a patient with pneumonia?

Answer 12

Crackles, bubbles and dull percussion, all related to fluid within the lungs.

Question 13

What abnormalities are seen on X-ray with pneumonia?

Answer 13

Consolidations, infiltrates and cavitations. May see fluid lines.

Question 14

What is CURB 65 score?

Answer 14

Used to asses severity of pneumonia.
Confusion? Urea above 7mmol/L, resp rate above 30, BP below 90/60, above 65 years. If score over 2, manage as severe pneumonia

Question 15

What investigations may be carried out for pneumonia?

Answer 15

FBC, UandE, CRP, Arterial blood gas, CXR, sputum and blood culture

Question 16

What tests would best confirm a viral cause of pneumonia?

What about legionella and pneumococcus?

Answer 16

Nose and throat swabs.

Urine antigen tests.

Question 17

What are some differential diagnoses for pneumonia?

Answer 17

Heart failure with pulmonary oedema,
Pulmonary embolism,
Atelectasis,
Lung cancer.

Question 18

How is pneumonia managed in UHL?

Answer 18

Moderate: Amoxicillin first line or doxycyline/clarithromycin if allergic for 5-7 days.

Severe: admit with coamoxiclav + clarithromycin/doxycyline for 7-10 days.

Question 19

What complications may be seen in pneumonia?

Answer 19

Empyema (infection spreads to pleural space), lung abscesses, bacteraemia and sepsis.

Question 20

What are the most common causes of hospital acquired pneumonia?

Answer 20

Staphylococcus aureus, MRSA, Pseudomonas species.

Question 21

How is hospital acquired pneumonia managed differently?

Answer 21

Coamoxiclav first line, piperacillin/tazobactam/meropenem second line

Question 22

Where is aspiration pneumonia commonly seen?

Answer 22

Epileptics, drowning, nursing home residents.

Question 23

What atypical organisms might cause pneumonia in the immune suppressed?

Answer 23

HIV - Pneumocystis Jirovecci, TB.
Neutropenia - Aspergillus species.
Splenectomy - encapsulated bacteria such as streptococcus pneumoniae

Question 24

What prevention options are there for pneumonia?

Answer 24

Flu vaccine annually for high risk patients,
Pneumococcal vaccines every 5 years,
Chemoprophylaxis for very high risk eg splenectomy.