6 Patterns > Acute Lung Injury > Subpatterns

Acute Lung Injury Subpatterns

There are 8 subpatterns in the setting of acute lung injury. We use the pneumonic C-DEB-FISH to remember to look for all the causes of acute lung injury.

  • C = Connective Tissue Disease (lymphoplasmacytic infiltrates, pleuritis)

  • D = Drug Reaction (foamy cytoplasm in macrophages and pneumocytes)

  • E = Acute Eosinophilic Pneumonia (eosinophils, fibrin, reactive pneumocytes)

  • B =Diffuse Alveolar Hemorrhage (blood and capillaritis)

  • F = Foreign Material (food, embolized material)

  • I = Infection (necrosis, granulomas, neutrophils, viral cytopathic effect)

  • S = Background Fibrosing ILD (scarring)

  • H = Hypersensitivity Pneumonitis (granulomas and cellular infiltrates)

Click the image most similar to your case.  It may be okay to see more than one pattern. 

w/ Hyaline Membranes

  • Infection

  • Drug Reaction

  • Connective Tissue Disease

  • Idiopathic (DAD/ARDS)

w/ Eosinophils

  • Acute eosinophilic pneumonia

  • Drug Reaction

  • Infection

  • DAD in smokers

w/ Granulomas

  • Infection

  • Subacute HP

w/ Neutrophils

  • Infection

  • Alveolar Hemorrhage Syndrome with capillaritis

w/ Necrosis

  • Infection

  • ANCA-Associated Disease

  • Infarction

w/ Foreign Material

  • Aspiration

  • Embolized Drug/chemo

  • Silicone pneumonia

w/ Hemosiderin Macrophages  

  • Acute and Organizing Alveolar Hemorrhage Syndrome

Image_239 copy.jpg

w/ Cellular Interstitial Infiltrates

  • Connective Tissue Disease

  • Subacute HP

w/ Background Fibrosis

  • Acute exacerbation of underlying ILD

Sample Signout of the Acute Lung Injury Biopsy

If no additional specific histologic features are identified, consider the following approach to signing the case out:

Acute and organizing lung injury (see comment).

Comment:  The biopsy shows acute and organizing lung injury.  There is a broad differential diagnosis including infection, drug reaction, CTD, aspiration, and as an idiopathic entity.  No additional specific histologic features to indicate an etiology are identified.  The diagnosis of ILD requires a multidisciplinary approach.  Correlation with microbiology studies, imaging studies and clinical history is suggested.