#radiology
see: [Cavitary Lung Diseases](bookends://sonnysoftware.com/ref/DL/3023), [Core Radiology - Cavitary and cystic lung disease](x-devonthink-item://C1EF00FD-576C-4C41-AE08-CA966611F572?page=29)
![[Pasted image 20241030225803.png]]
**DDx**
- infections
- [[Tuberculosis]] -- upper lobe cavitary consolidation
- fungal pneumonia
- cryptococcus
- aspergilliosis
- cavitary bacterial pneumonia
- eg staph, klebsiella, pseudomonas, staph auereus
- necrotising pneumonia
- lung abscess
- [[Endocarditis|septic emboli]] (usually multiple cacitary lesions)
- non-infectious
- *primary bronchogenic carcinoma* (usually SCC)
- vasculitis (eg granulomatosis w/ polyangiitis -- usually multiple cavitary lesions)
- metastasis from other malignancy -- multiple
- pulmonary infarction from pulmonary embolism or septic emboli
- [[Sarcoidosis]]
![[Pasted image 20241030224149.png]]
## DDx table
| Cavity | patient | radiographic findings | |
| -------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------- |
| lung abscess | - [[Alcohol-related disease\|alcoholism]]<br>- diabetes<br>- [[IVDU issues\|IVDU]]<br>- elderly | - unilateral and solitary cavities w/ thick, irregular walls<br>- often with an *air fluid level*<br>- usually posterior segments of upper lobes and superior segments of lower lobes | ![[Pasted image 20241030224733.png]] |
| necrotising pneumonia | - diabetes<br>- alcoholism<br>- immunosuppression<br>usually severely ill; may have resp failure and shock<br><br>often S aureus, S pneumoniae, klebsiella, H flue, pseudomonas | unilateral and solitary pulm consolidation w/ multiple foci of poorly-defined low density areas of necrosis | ![[Pasted image 20241030225211.png]] |
| septic emboli | - CVCs<br>- PPMs<br>- right-sided prosthetic valves<br>- IVDU<br>- [[Lemierre's syndrome]] | multiple, bilat, peripherally located cavitating nodules. usually different stages of cavitation | ![[Pasted image 20241030225238.png]]<br>![[Pasted image 20241030225724.png]] |
| nocardia | | | |
| cryptococcus | - pigeon droppings exposure<br>- [[HIV]]<br>fever, cough, dysponea, headache | multiple bilat, peripheral nodules and masses that cavitate<br> | |
| invasive pulm aspergilliosis | prolonged neutropenia, T-cell def, organ transplant<br>- may have [[Haemoptysis]] | solitary or multiple nodules with a halo sign | |
| [[Tuberculosis]] | [[HIV]], endemic region, exposure history<br>chronic cough, weight loss, fevers, night sweats, [[Haemoptysis]] | cavitation occurs in apical and posterior segments of upper lobes . solitary or multiple cavities with thick, irregular walls | ![[Pasted image 20241030230956.png]]<br>![[Pasted image 20241030225648.png]] |
| primary malignancy | smoking history, FMx lung cance, asbestos exposure. [[Haemoptysis]] | irregular internal wall. usually solitary with an upper lobe predominance | |
| metastatic malignancy | | multiple bilat pulm nodules | |
| rheumatoid arthritis | history of RA, joint pains, fevers | | |
| granulomatosis with polyangiitis | history of this. may have rhinosinusitis, epistaxis, fever, malaise, haemoptysis | multiple bilat pulm nodules | |
## Cavitary mimics
| mimic | definition | |
| ------------------------- | --------------------------------------------------------------------------------------------- | ------------------------------------ |
| cyst | round parenchymal lucency w/ well-defined thin wall | ![[Pasted image 20241030224304.png]] |
| emphysema | focal area or regions of low attenuation, usually w/o visible walls | ![[Pasted image 20241030224336.png]] |
| infected bullae | radiographic evidence of previous bullous disease and the development of an *air fluid level* | ![[Pasted image 20241030224418.png]] |
| cystic [[Bronchiectasis]] | lack of bronchial tapering and a ↑ bronchoarterial ratio | |