Lung abscess is a localized cavity in the lung caused by infection, usually from Staphylococcus or Streptococcus bacteria. It can be putrid or non-putrid depending on whether anaerobic or aerobic bacteria are involved. Lung abscesses are commonly caused by aspiration of infected material from the mouth or throat, or following a pulmonary infection like pneumonia or bronchiectasis. Symptoms include coughing up copious purulent sputum. Management involves identifying the causative bacteria through culture and treating with appropriate antibiotics.

1. Respiratory Pathology
Lung Abscess
By W, Ruto

2. • Lung abscess is a localized supurative cavity of
infective origin resulting from patches of lung
tissue with surrounding pneumonitis; usually
caused by staphs or strepts.
• Lung abscess may be of putrid or non putrid
nature.
• Putrid has foul smelling abscess caused by
anaerobes whereas non putrid is caused by
aerobes.

3. Aetiology
1. Aspiration of infected material as in aspiration of
organisms which inhabit teeth or tonsils
following dental procedures, aspiration of
infected foreign body or aspiration of pus from
mouth to lungs.
2. May follow pulmonary infections as in
bronchopneumonia complicating to lung
abscess, bronchiectasis or rarely lobar
pneumonia.

4. 3. Bronchial obstruction secondary to conditions
including bronchial carcinoma.
4. Blood borne infection from a distant foci as in
septicaemia.
Appearance of Lung Abscess
• There is pus-filled cavity in the lung parenchyma
surrounded by variable sizes of fibrous scarring
tissue due to attempt of tissues to heal.
•

5. Results of Lung Abscess
• Abscess may open up to the brochus thus
patient produce copious purulent sputum.
• Abscess may perforate into pleural space
resulting in empyema.
• May cause metastatic abscesses formation
including abscess to the brain and other parts
of the body.

6. Differential Diagnosis
1. Bronchiectasis.
2. Chronic Bronchitis.
3. PTB.
4. Bronchogenic carcinoma.
5. Primary lung empyema.
6. Bronchopleural fistula.

7. Management
• Sputum/pus smear for culture & sensitivity.
• Appropriate antibiotics as per c/s.
• Postural drainage.
• Dissection of the lung- drainage of the
abscess.