Synopsis
Recognise pulmonary parenchymal necrosis, identify sepsis, haemorrhage and an obstructing lesion early, and coordinate microbiology-led prolonged therapy with drainage or surgery only when source control is genuinely needed. Verify treatment against current antimicrobial, respiratory, radiology and thoracic-surgical guidance.
- A lung abscess is a localised pus-containing cavity; necrotising pneumonia is more diffuse parenchymal destruction with multiple small cavities and may progress rapidly.
- Aspiration, poor dentition, impaired consciousness, swallowing dysfunction, an obstructing tumour, immunosuppression and septic emboli are high-yield causes or contributors.
- CT with contrast usually characterises cavitation, distinguishes pleural empyema and looks for obstruction, infarction, foreign body or malignancy.
Key red flags
Rapid hypoxaemia, shock, high inflammatory burden, multilobar consolidation and evolving small cavities, sometimes after influenza. Escalate early because deterioration and organ failure can be abrupt.
Investigation priorities
Confirm consolidation or a cavity, identify an air-fluid level and detect pneumothorax or pleural fluid rapidly.
Management branches
Hypoxaemia, shock, altered mental state, major haemoptysis or rapidly progressive cavitation.
- Use an ABCDE approach, controlled oxygen to an individual target, blood cultures and lactate, prompt sepsis antimicrobials and early critical-care review.
- Obtain urgent contrast CT when the patient can safely transfer; involve respiratory medicine, microbiology and radiology, and call thoracic surgery or interventional radiology early for haemorrhage, fistula or non-viable lung.
Key medicines
Co-amoxiclavFor a stable adult, a locally approved oral or intravenous regimen selected for severity and renal function; verify current BNF and antimicrobial policy rather than copying a generic dose.
Piperacillin with tazobactamIntravenous hospital regimen adjusted for renal function and local extended-infusion policy; confirm current BNF and microbiology advice.