Onion peel sign

The onion peel sign (also called the Cumbo sign or double arch sign) is a feature seen with complicated pulmonary hydatid cyst in which the gas lining between the endocyst and pericyst has the appearance of an onion peel. It is pathognomonic for a ruptured hydatid cyst.

History and etymology

It was first described by Cumbo in 1921 2.

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Article information

rID: 21007
System: Chest
Section: Signs
Synonyms or Alternate Spellings:
  • Cumbo sign
  • Onion peel sign in pulmonary hydatid didease
  • Double arch sign (hydatid)

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