Lobster claw sign (kidney)

Lobster claw sign refers to a urographic pattern of papillary excavation that may be seen with renal papillary necrosis.

The lobster claw sign occurs when there is excavation around the edge of the papilla and the contrast material that extends into this excavated region looks like the "claws" of a lobster when viewed en face.

This patterns of papillary excavation is most often seen with 


Inspired signs
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Article Information

rID: 21577
System: Urogenital
Tags: refs, cases
Synonyms or Alternate Spellings:

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Cases and Figures

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    Figure 1: lobster
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    Normal renal calyx
    Figure 2: normal calyx
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    "Lobster claw" mo...
    Figure 3: lobster claw papillary necrosis
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