Stump appendicitis is inflammation of the residual appendiceal stump following previous appendectomy. A rare but important clinical entity (incidence <0.01%). Diagnosis of appendicitis is typically delayed due to history of appendectomy. CT shows an enhancing residual structure at the cecal base, pericecal stranding, and cecal pole wall thickening.
Age Range
15-70
Peak Age
35
Gender
Equal
Prevalence
Rare
Stump appendicitis results from inadequate resection of the appendiceal base during appendectomy. The residual stump is typically 0.5-3 cm in length with preserved internal mucosal surface. The same pathophysiological process as primary appendicitis operates in this residual structure: obstruction of the stump lumen (fecalith, mucus accumulation, lymphoid hyperplasia), increased intraluminal pressure, mucosal ischemia, and bacterial superinfection. Laparoscopic appendectomy carries higher risk of leaving a longer stump than open surgery because visualization of the appendiceal base may be difficult. On CT, inflammation of the residual structure at the cecal base presents with the same findings as acute appendicitis (wall thickening, enhancement, pericecal stranding) but clinicians may not consider this diagnosis due to appendectomy history.
On CT, the combination of an enhancing, thick-walled tubular residual structure at the cecal base distal to appendectomy clips/stapler line with pericecal fat stranding is the pathognomonic finding of stump appendicitis. This finding must be kept in mind when evaluating right lower quadrant pain in patients with appendectomy history.
Enhancing tubular residual structure (stump) with thickened wall at the cecal base distal to surgical clips/stapler line. Stump length typically measures 0.5-3 cm with diameter >6 mm. Wall enhancement is as prominent as in inflamed appendix.
Report Sentence
An enhancing tubular stump structure measuring ... cm in length with thickened wall is identified at the cecal base distal to surgical clips, consistent with stump appendicitis.
Pericecal fat stranding is seen around the stump and adjacent to the cecal pole. Stranding is typically as prominent as in acute appendicitis but localized to the cecal base.
Report Sentence
Pericecal fat stranding is noted around the cecal base and stump.
Reactive thickening and enhancement of the cecal pole wall indicates spread of stump inflammation to the cecum. Focal asymmetric thickening may mimic cecal carcinoma and requires attention in differential diagnosis.
Report Sentence
Reactive thickening of the cecal pole wall is noted.
Surgical clips or stapler line from previous appendectomy are identified as metallic density structures at the cecal base. The residual stump structure distal to the clips is the diagnostic clue.
Report Sentence
Surgical clips from previous appendectomy are noted at the cecal base.
Calcified fecalith or fecal material accumulation in the stump lumen indicates the cause of obstruction. Appendicolith frequency in stump appendicitis is higher than primary appendicitis because the short stump lumen is more susceptible to obstruction.
Report Sentence
Calcified fecalith in the stump lumen is noted, supporting obstructive stump appendicitis.
On ultrasound, a tubular, non-compressible, thick-walled structure is identified adjacent to the cecal base. Surgical clips may be detected as hyperechoic structures. Pericecal hyperechoic fat stranding accompanies.
Report Sentence
A non-compressible tubular structure distal to surgical clips adjacent to the cecal base is noted; stump appendicitis should be considered.
Criteria
Developing within first year after appendectomy, typically associated with long stump (>1 cm)
Distinct Features
May have history of inadequate resection or technical difficulty (appendiceal inflammation, anatomical variation). On CT, the stump is more prominent and easily detected.
Criteria
Developing years-decades after appendectomy, may occur with shorter stump (<1 cm)
Distinct Features
Diagnosis is more difficult because appendectomy history may have been long forgotten. On CT, the stump may be short and difficult to detect; thin-section reconstructions and multiplanar reformats are critical.
Distinguishing Feature
Primary acute appendicitis lacks appendectomy history and surgical clips; in stump appendicitis, clips and short residual structure at the cecal base are diagnostic clues
Distinguishing Feature
Diverticulitis shows focal outpouching and localized inflammation; stump appendicitis has surgical clips and residual tubular structure
Distinguishing Feature
Adenocarcinoma shows irregular solid mass and regional lymphadenopathy; stump appendicitis lacks focal mass with predominant inflammatory pattern
Urgency
emergentManagement
surgicalBiopsy
Not NeededFollow-up
no-follow-upStump appendicitis is a surgical emergency like acute appendicitis. Treatment involves completion appendectomy (complete resection of the stump). Delayed diagnosis increases perforation and abscess risk. Stump appendicitis must be considered in right lower quadrant pain in patients with appendectomy history. Detailed description of surgical clips and stump structure in the radiology report is critical information for the surgeon. Leaving the stump shorter than 3 mm during appendectomy is recommended to prevent this complication.
Treatment of stump appendicitis is completion resection of the stump (stump appendectomy). Diagnostic delay can result in perforation and abscess. This diagnosis should be considered when evaluating RLQ pain in patients with appendectomy history. In laparoscopic appendectomies, leaving a stump less than 5 mm is recommended.