Pneumotox » Drug » Semustine (methyl-CCNU) » XV.i - Path: Pneumocyte atypia (reactive epithelial cells) (a.k.a. the "Napoleon Hat" sign)

Semustine (methyl-CCNU)

Last update : 17/12/2013

Diagnosing DIRD

Drug and radiation history

Drug singularity - Correct identification of the drug

Consistent timing of exposure v. onset of symptoms

Clinical, imaging, BAL, pathological pattern consistent with the specific drug

Careful exlusion of another cause

Remission of symptoms with removal of drug

Recurrence with rechallenge (rarely advisable)

Causality assessment