Abscess due to perforated appendicitis: factors associated with successful percutaneous drainage

• This is the largest retrospective study of percutaneous appendiceal abscess drainage.
• Low abscess grade was associated with success. Abscess size was not significant.
• CT guidance and transgluteal approach were associated with success.
• Postdrainage fistulas occur 13% of the time and most of them close spontaneously.

BackgroundPercutaneous drainage is the standard treatment for perforated appendicitis with abscess. We studied factors associated with complete resolution (CR) with percutaneous drainage alone.MethodsNinety-eight patients underwent percutaneous drainage for acute appendicitis complicated by abscess (October 1990 to September 2010). CR was defined as clinical recovery, resolution of the abscess on imaging, and drain removal without recurrence. Patients achieving CR were compared with patients not achieving CR.ResultsThe rate of CR was 78.6% (n = 77). Abscess grade was the only radiological factor associated with CR (P = .007). The CR rate was higher with transgluteal drainage (90.9% vs 79.2%) than with other anatomic approaches (P = .018) and higher with computed tomography-guided drainage than with ultrasound-guided drainage (82.7% vs 64.3%, P = .046).ConclusionCR was more likely to be achieved in patients with lower abscess grade, computed tomography-guided drainage, and a transgluteal approach.