IS Case 577: Acute appendicitis and ureterolithiasis with mild right hydroureter

Narasimhachar G. Prativadi, MD

Imaging Sciences URMC

Imaging Sciences URMC 2010
Publication Date: 2011-11-17


Patient is a 36-year-old male with eleven hours of 10/10 right lower quadrant pain. He also complained of nausea. History is significant for numerous instances of nephrolithiasis requiring lithotripsy and basket extraction. Physical exam was positive for tenderness at McBurney's point.


Imaging findings included mild right hydroureter, right ureteral stone, inflamed appendix with surrounding fatty changes and appendicolith.


Acute appendicitis and ureterolithiasis with mild right hydroureter


This is a unique patient who had a story which sounded like both urolithiasis and appendicitis, and ended up having both at the same time.

Appendicitis is caused by obstruction of the appendiceal lumen, leading to venous obstruction, ischemia, bacterial invasion, and finally necrosis. CT features of acute appendicitis include appendiceal thickness of 6 mm, thickened walls, surrounding fat stranding, proximal filling and distal inflammation, asymmetric cecal wall thickening, adenopathy at the mesoappendix, and calcified appendicolith (seen in 28-30% of all cases).

In acute ureteral obstruction, a stone is seen within the ureter, most commonly at the UVJ or at the UPJ. Stones larger than 6 mm have difficulty passing on their own. The tissue rim sign is a good way of spotting ureteral stone; this is when a circle of soft tissue is seen surrounding the stone. Findings that may be associated with an obstructive ureteral stone include perinephric or periureteral fat stranding, hydronephrosis, dilated ureter proximal to the obstruction.


  1. Webb RW, Brant W, Major N. Fundamentals of Body CT. 3rd Ed. Philadelphia, PA: Saunders Elsevier, 2006.
  2. Weissleder R, Wittenberg J, Harisinghani MG. Primer of Diagnostic Imaging. Philadelphia, PA: Mosby Elsevier, 2007.

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