Synopsis
Recognise organising pneumonia as a clinicoradiological syndrome, exclude secondary causes and infection, and use specialist corticosteroid treatment with relapse-aware monitoring.
- Organising pneumonia is a tissue-repair pattern with intra-alveolar granulation tissue; cryptogenic organising pneumonia is diagnosed only when no cause is found.
- Secondary triggers include infection, connective-tissue disease, medicines, radiotherapy, malignancy, inflammatory bowel disease and transplantation.
- Patients often have weeks of dry cough, breathlessness, fever, malaise and weight loss that fail to resolve with routine antibiotics.
Key red flags
Rapidly spreading bilateral opacity, profound desaturation, tachypnoea or exhaustion can resemble ARDS and requires emergency respiratory and critical-care assessment.
Investigation priorities
Define extent, distribution and features requiring another pathway.
Management branches
Subacute multifocal consolidation persists despite appropriate initial antimicrobial care.
- Reassess physiological stability and obtain HRCT, looking for organising distribution while identifying pleural, nodal or mass-like features that require a cancer or infection pathway.
- Review all medicines, radiotherapy, systemic inflammatory symptoms, immune status and microbiology; do not use the word cryptogenic until secondary causes have been addressed.
Key medicines
PrednisoloneThere is no single current UK regimen for COP; specialist practice uses a daily induction tailored to physiological severity, followed by a slow response-guided taper over months under the local ILD protocol.
Long-term macrolide in selected casesNo routine COP dose should be copied across services; if an ILD specialist uses azithromycin or clarithromycin off label, follow the BTS macrolide and local antimicrobial protocol exactly.