Acute bronchitis

Question 1

What is acute bronchitis?

Answer 1

a type of chest infection

Inflammation of the large airways of the LRT where the pulmonary parenchyma is not affected

Question 2

What is a characteristic of acute bronchitis?

Answer 2

It is usually self-limiting in nature

Question 3

How long does acute bronchitis last?

Answer 3

Usually resolves within 3 weeks (1-3 weeks)

But in 25% patients, cough can last longer

Question 4

What is acute bronchitis a result of? And what is it associated with?

Answer 4

It is a result of inflammation of the trachea and major bronchi and is therefore associated with oedematous large airways and the production of sputum

Question 5

What kind of cough is acute bronchitis usually associated with?

Answer 5

cough worse at night or with exercise

May be a/w bronchospasm and/or excessive mucus

Question 6

Define acute bronchitis

Answer 6

a self-limiting LRTI

Question 7

What is the leading cause of acute bronchitis?

Answer 7

• Viral infection is the leading cause
• Uncertainty regarding the exact proportion of pathogens giving rise to acute bronchitis

Question 8

What can precede acute bronchitis?

Answer 8

URTI

Question 9

When do episodes usually occur?

Answer 9

~ 80% occur in autumn or winter

Question 10

What ages does acute bronchitis usually affect?

Answer 10

Children and adolescents more commonly affected

Question 11

How do patients with acute bronchitis usually present?

Answer 11

Acute onset of:
- Cough: may or may not be productive
- Sore throat
- Rhinorrhoea
- Wheeze

Question 12

What signs do patients present with?

Answer 12

• Most have a normal chest examination
• Some may have low-grade fever and wheeze

Question 13

How can acute bronchitis be differentiated from pneumonia?

Answer 13

1. History
   - Sputum, wheeze, breathlessness may be absent in acute bronchitis. At least one of these usually present in pneumonia.
2. Examination
   - Acute bronchitis: no other focal chest signs (dullness to percussion, crepitations, bronchial breathing) other than wheeze.
   - Acute bronchitis: systemic features absent (malaise, myalgia, fever) – these tend to be present in pneumonia.
3. Pathophysiology
   - Bronchitis: infections causing inflammation in bronchial airways
   - Pneumonia: infection in the lung parenchyma resulting in consolidation of the affected segment or lobe

Question 14

What investigations are involved?

Answer 14

• Typically clinical diagnosis
• CRP may be used to guide abx therapy
• Also ?CXR, Pulmonary function test

Question 15

How is acute bronchitis managed?

Answer 15

• Analgesia
• Good fluid intake
• ?abx

Question 16

When should abx therapy be considered in acute bronchitis?

Answer 16

If patient:
- Systemically unwell
- Pre-existing co-morbidities - CRP 20-100 mg/L –> offer delayed prescription
- CRP >100mg/L –> offer abx immediately

Question 17

What abx may be used in acute bronchitis?

Answer 17

1st line: Doxycycline

Alternative: amoxicillin

Question 18

When is doxycycline c/I?

Answer 18

Can’t be used in children or pregnant women

Question 19

MacFarlane criteria for diagnosis

Answer 19

1. Acute illness <21 days
2. Cough is predominant symptom
3. 1 or more other lower respiratory tract sx (g. sputum, wheeze, chest pain)
4. No other alternative diagnosis

Question 20

What are key diagnostic factors?

Answer 20

• presence of risk factors
• duration of cough <30 days
• productive cough
• no history of chronic respiratory illness

Question 21

What are other diagnostic factors?

Answer 21

fever
wheezes
rhonchi

Question 22

What are risk factors?

Answer 22

• viral or atypical bacterial infection exposure
• cigarette smoking
• household pollution exposure

Question 23

What are other causes for acute cough?

Answer 23

Pneumonia
Asthma
Postnasal drip

Question 24

What are complications of acute bronchitis?

Answer 24

Postbronchitis syndrome
(can produce a cough lasting several months)