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Case of the Week 379

What sign is depicted on this image?

  • 58 year-old with abdominal pain and diarrhea

Axial CT view of abdomen with oral contrast

1. String sign
2. Egg-on-a-string sign
3. Accordion Sign
4. Mercedes Benz sign
5. Colon cut-off sign

Additional Images - None


Additional Images






3. Accordion sign



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Accordion Sign

General Considerations

  • The sign was originally described as alternating edematous haustral folds separated by mucosal ridges filled with oral contrast material
  • Simulated appearance of an accordion
  • It was first thought to be specific for severe Clostridium difficile–related colitis (pseudomembranous colitis)
    • Almost all cases of pseudomembranous colitis are associated with recent antibiotic therapy
  • C. difficile is the largest single cause of this sign

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