Lower respiratory tract infections Flashcards
Should the lower airway be colonised with bacteria?
No
What is acute bronchitis?
Inflammation of the bronchi usually caused by infection
What pathogens usually cause acute bronchitis?
Viruses usually
Bacteria:
H. influenzae
Strep. pneumonia
Many more
What are the symptoms of acute bronchitis?
Cough: productive or non
SOB
Wheeze
Fever
Do you get systemic involvement in bronchitis?
No, but you do get a fever
What would you find on a CXR with acute bronchitis?
Not a lot
No focal consolidation like there would be with pneumonia
Investigations for acute bronchitis.
ABG: if O2 levels are low and CO2 levels high then consider admission
CXR: no consolidations signs of pneumonia
Treatment of acute bronchitis.
If viral, just supportive care: pain relief, fluids, rest.
If bacterial: antibiotics
What problems can occur if you have COPD or asthma and you get acute bronchitis?
How would you manage this?
Exacerbation
Manage with inhalers + steroids
What is augmentin?
An antibiotic containing amoxicillin and clavulanate
What is pneumonia?
Inflammation of lung parenchyma
Who is at risk of getting pneumonia?
Extremes of age
COPD and other chronic lung diseases
Immunocompromised
Nursing home residents
Impaired swallowing
Diabetes
Congestive heart failure
Alcoholics + drug users
How is pneumonia classified?
Anatomically:
- lobar
- bronchopneumonia
Aetiologically: by the pathogen causing it
What are the causes of pneumonia?
Infection:
- usually bacteria
- sometimes virus
Unknown
Chemical
- aspiration of vomit
Radiotherapy
Which pathogens most commonly cause pneumonia?
Bacteria
- S. pneumonia
- Mycoplasma species
- Chlamydophila pneumonia
- Legionella
- H. influenzae
- Mycobacterium tuberculosis
Where do people come across Legionella?
Water tanks
Stagnant water
Travel
What is consolidation?
Alveolar space that contains liquid instead of gas
It appears as white on an X-ray
It is a sign of pneumonia
How does consolidation occur?
When an infection occurs in the distal airways, an inflammatory response occurs
So neutrophils and inflammatory exudate fill the alveolar space
Fluid accumulates = consolidation
What are symptoms of pneumonia?
Fever Cough Sputum sometimes SOB Pleuritic chest pain Systemic features: fever, night sweats Extra-pulmonary features: neurological
What can sputum tell you about pneumonia?
Rusty sputum is suggestive of S. pneumonia
Non-productive suggests Mycoplasma, Chlamydophila, Legionella
What are the signs of pneumonia?
Abnormal vital signs:
- fever
- raised HR
- raised resp rate
- low BP
Signs of lung consolidation on percussion and auscultation
Hypoxia, signs of respiratory failure
What are the signs of lung consolidation you can hear?
Dull to percussion Decreased air entry Bronchial breath sounds Crackles plus wheeze Aegophony
What is aegophony and how do you test for it?
Ask the patient to say ‘e’ and listen to the lungs with a stethoscope
If they show aegophony the ‘e’ sound they are making will sound like an ‘a’
Investigations for pneumonia?
CXR: show areas of consolidation
Also look for cavities (TB) and signs of cancer
Sputum
Bloods:
- WBCs - marker for severity
- U&E
- LFT
- CRP - marker for severity
Pulse oximetry
ABG: low O2 and high CO2 means it is severe
Microbiological tests
Urinalysis
