Water-lily sign (hydatid cyst)

The water-lily sign, also known as the camalote sign,  is seen in hydatid infections when there is detachment of the endocyst membrane which results in floating membranes within the pericyst that mimic the appearance of a water lily.

It is classically described on plain radiographs (mainly chest X-ray) when the collapsed membranes are calcified but may be seen on ultrasound, CT and MRI.

Inspired signs
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Article information

rID: 2281
Section: Signs
Tag: lung
Synonyms or Alternate Spellings:
  • Camalote sign
  • Water lilly sign
  • Waterlily sign
  • Water-lilly sign
  • Water lily

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Cases and figures

  •  Case 1: chest radiograph
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  • Case 1: CT
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  • Case 2: liver ultrasound
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  • Detachment of End...
    Case 3: liver ultrasound
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  • Case 4: liver ultrasound
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  • Case 5
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