An appendicolith is a calcified deposit within the appendix. They are present in a large number of children with acute appendicitis and may be an incidental finding on an abdominal radiograph or CT. Incidence may be increased among patients with a retrocecal appendix. Overall they are seen in 10% of patients, with 90% subsequently going on to develop appendicitis 3.


Although the cause of appendicolith formation is uncertain, some case reports have mentioned an ingested foreign body or a dislodged gallstone eroding through the gallbladder as possible etiologies. 

Radiographic features

If identified on ultrasound, an appendicolith will appear cast an acoustic shadow. On abdominal radiograph or CT, a high attenuation stone may be seen in the right iliac fossa. CT is more sensitive than plain film. Up to 25% show laminated calcification.

Article information

rID: 5635
Synonyms or Alternate Spellings:
  • Appendicoliths

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Cases and figures

  • Case 1: CT
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  • Case 2: on abdominal radiograph
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  • Case 3: ultrasound
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  • Appendicolith
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  • Case 5: appendicitis and appendicolith
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  • Case 6
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