LOBAR PNEUMONIA

Question 1

What is pneumonia?

Answer 1

Acute inflammation with an intense infiltration of neutrophils in and around the terminal bronchioles. The affected bronchopulmonary segment or the entire lobe may be consolidated by the resulting inflammation and oedema.

Question 2

What is CAP?

Answer 2

Pre-hospital or within 1st 24hrs

Question 3

What is HAP?

Answer 3

More than 24hrs post-admission

Question 4

What is the mortality rate?

Answer 4

21% in hospital

Question 5

What age group is most affected?

Answer 5

Elderly. Only 30% are <65 years

Question 6

What are the most common organisms?

Answer 6

S. pneumoniae, S. aureus, Mycoplasma pneumoniae, Haemophilus influenzae, Chlamydophila pneumoniae and respiratory viruses. Mixed pathogens occur up to 25% of the time.

Question 7

Most common Aetiology of CAP?

Answer 7

may be primary or secondary to underlying disease
o Streptococcus pneumoniae is commonest cause
o Then H influenzae, Mycoplasma pneumonia
o Staph A, Legionella speciies, Moraxella catarrhalis and Chlamydia = rest of bacteria
o Gram -ve and anaerobes are rare
o Viruses only 15%

Question 8

Aetiology of HAP?

Answer 8

o Acquired >48hrs after hospital admission
o Most commonly due to G -ve bacteria or Staph A
o Anaerobes
o Also Pseudomonas, Klebsiella, Bacteriodes, Clostridia

Question 9

Aetiology of aspiration pneumonia?

Answer 9

o Usually due to vomit
o Occurs in those with stroke, myasthenia, bulbar palsies, decreased consciousness (drunk), oesophageal disease (achalasia, reflux), poor dental hygiene
o Staph pneumoniae and anaerobes

Question 10

Aetiology in the immunocompromised patient

Answer 10

o Strep pneumoniae, H influenza, Staph A, M catarrhalis, M pneumoniae, G -ve bacilli, Pneumoncystic jiroveci (used to be named P carinii)
o Fungi
o Viruses

Question 11

2 other aetiology’s of

Answer 11

• Radiotherapy

* Allergic mechanisms

Question 12

What risk factors?

Answer 12

Age - elderly and very young
Lifestlye: smoking and alcohol
Prev. Viral infections: influenza or parainfluenza
Resp disease: asthma, COPD, malignancy, bronchiectasis, cystic fibrosis
Immunosuppresion: AIDS, cytotoxic therapy.
IV drug abuse (staph. Aureus infection)
Hospitalisation
Underlying comorbidities: DM, CV disease etc.

Question 13

What symptoms?

Answer 13

Cough, purelent sputum (rust-coloured or blood-stained), breathlessness, fever, malaise.
Elderly: malaise, faitugie, anorexia and myalgia.
Young children: unspecific or abdominal pain

Cough, purulent sputum, fever, rigors, malaise, anorexia, dyspnoea. Heamoptysis, pleuritic pain

Question 14

What signs?

Answer 14

Tachypneoa, bronchial breathing, crepitatoins, pleural rub, dullness with percussion.
Pyrexial, cyanosis
Confusion
Tachypnoea, tachycardia
Hypotension
Resp exam:
Reduced expansion. Dull to percussion. Increased tactile vocal fremitus. Bronchial breathing. Pleural rub. Bibasal crackles if pleural effusion

Question 15

What is CURB-65?

Answer 15

• Confusion
• Urea >7mmol
• Resp rate 30/min+
• Systolic pressure below 90, or diastolic below 60
• Age > 65yrs

Question 16

What does CURB-65 mean?

Answer 16

Score >2, admission to hospital. Less = treat at home. More = ?ICU
ABG/O2 sats of <8KPa/92%; co-morbidity; multilobar/bilateral involvement also indicate severe disease)

Question 17

What investigations?

Answer 17

Pneumococcal and legionella urinary antigen tests.
CXR. (A follow-up CXR six weeks after recovery from pneumonia is recommended.) - consolidation
Sputum examination and culture.
Pulse oximetry or blood gases.
Aspiration of pleural fluid (for biochemistry and culture).
Bloods:
FBC with differential white cell count.
Raised CRP/ ESR - CRP (to aid diagnosis and as a baseline measure).
Blood cultures
Renal function and electrolytes.
LFTs.
Bronchoscopy/ bronchoalveolar lavage

Question 18

What management?

Answer 18

Prevention:
•	Early antibiotic therapy
•	Influenza and pneumococcal vaccination
•	Targeted risk reduction i.e. Smoking cessation
Not to smoke, rest and drink lots of fluids
Oxygen for hypoxia
Fluids for dehydrators
Analgesics: NSAID's
Nebuliser saline may help expectoration
Chest physio therapy

Question 19

What antibiotic treatment do you offer?

Answer 19

Mild - 5 day course of Amoxicillin (macrolide or tetracycline if allergic to penicillin). Add Flucloxicillin if Staph infection suspected
Moderate: 7-10 day course of antibiotics. Amoxicillin with a macrolide
Severe: a beta-lactamase stable beta-lactate and a macrolide

Question 20

What is the progression of treatment?

Answer 20

Oral antibiotics – if not severe and not vomiting; amoxicillin/clarithromycin/doxycycline
IV antibiotics – if severe; co-amoxiclav/cephalosporin + clarithromycin
O2 - if low sats
IV fluids - if anorexia, shock or dehydration
Analgesia - if pleurisy
ITU - if shock, hypercapnia, uncorrected hypoxia; if CRP remains high or failure to improve then look for progression/complications

Question 21

What is the best way of preventing it?

Answer 21

Pneumoccocal vaccine – offer to at risk groups i.e. >65yo, chronic heart, liver, kidney or lung failure/conditions, DM, immunosuppressed, small spleen, AIDS, chemotherapy

Question 22

What are the differentials?

Answer 22

• Different organism responsible.
• Pulmonary oedema.
• Pleural effusion.
• Pneumothorax.
• Pulmonary embolus.
• Asthma.
• COPD.
• Bronchiectasis.
• Fibrosing alveolitis.
• Neoplasm.
• Sarcoidosis.
• Pneumonia complication - eg, empyema, lung abscess.

Question 23

What are the complications?

Answer 23

• Pleural effusion that is usually sterile.
• Empyema: a reactive effusion can occur but is trivial. Empyema is potentially more serious and presents as the persistence of fever and leukocytosis after 4-5 days of appropriate antibiotic therapy.
• Lung abscess: can occur in disease due to S. pneumoniae and is classically seen in patients with klebsiella or staphylococcal pneumonia.
• Pneumatocele.
• Pneumothorax.
• Pyopneumothorax - eg, following rupture of a staphylococcal lung abscess in the pleural cavity.
• Deep vein thrombosis.
• Septicaemia, pericarditis, endocarditis, osteomyelitis, septic arthritis, cerebral abscess, meningitis (particularly in pneumococcal pneumonia).
• Postinfective bronchiectasis.
• Acute kidney injury.

Question 24

What is the prognosis?

Answer 24

Mortality from CAP <1% of those well enough to be looked after in the community.
Hospital admissions: 5-10%
Incubated patients: 25%
ICU patients: 50%
Legionella has the most severe course and most significant morbidity