Management of Postoperative Intra-abdominal Abscess/Phlegmon After Laparoscopic Appendectomy

Diagnostic Approach

A step-up approach should be used for diagnosis, starting with clinical and laboratory examination, followed by imaging studies tailored to hospital resources 3
Clinical features suggestive of postoperative abscess include persistent fever, tachycardia, palpable mass, and extension of tenderness and rebound in the right lower quadrant 4

The first-line management for postoperative intra-abdominal abscess or phlegmon after laparoscopic appendectomy is percutaneous image-guided drainage combined with appropriate antibiotic therapy, with surgical intervention reserved for cases where percutaneous drainage is not available or feasible 1, 2
For larger abscesses, percutaneous image-guided drainage is the preferred first-line intervention, combined with appropriate antibiotic therapy 1, 2, 3
Consider conservative management with close clinical monitoring for smaller abscesses 2, 5

Piperacillin/tazobactam or alternative regimens such as Metronidazole plus a broad-spectrum antibiotic may be used for stable patients 1, 3
For critically ill patients, Meropenem, Doripenem, or Imipenem/Cilastatin, plus Metronidazole, may be used, with consideration of adding Vancomycin if MRSA is suspected 1, 3

Routine use of intra-operative irrigation during the initial appendectomy does not prevent intra-abdominal abscess formation and may be avoided 6

Interval appendectomy is not routinely necessary following successful non-operative treatment of complicated appendicitis, but should be performed for patients with recurrent symptoms 5
For patients ≥40 years old with complicated appendicitis, both colonoscopy and interval full-dose contrast-enhanced CT scan are recommended for follow-up, according to the Praxis Medical Insights guideline society 7