Manejo del plastron apendicular

META-ANALYSIS

Nonsurgical Treatment of Appendiceal Abscess or Phlegmon
A Systematic Review and Meta-analysis
Roland E. Andersson, PhD, MD,*† and Max G. Petzold, PhD‡

Objective: A systematic review of the nonsurgical treatment of patients with appendiceal abscess or phlegmon, with emphasis on the success rate, need for drainage of abscesses, risk of undetected serious disease, and need forinterval appendectomy to prevent recurrence. Summary Background Data: Patients with appendiceal abscess or phlegmon are traditionally managed by nonsurgical treatment and interval appendectomy. This practice is controversial with proponents of immediate surgery and others questioning the need for interval appendectomy. Methods: A Medline search identified 61 studies published between January 1964and December 2005 reporting on the results of nonsurgical treatment of appendiceal abscess or phlegmon. The results were pooled taking the potential clustering on the study-level into account. A meta-analysis of the morbidity after immediate surgery compared with that after nonsurgical treatment was performed. Results: Appendiceal abscess or phlegmon is found in 3.8% (95% confidence interval (CI),2.6 – 4.9) of patients with appendicitis. Nonsurgical treatment fails in 7.2% (CI: 4.0 –10.5). The need for drainage of an abscess is 19.7% (CI: 11.0 –28.3). Immediate surgery is associated with a higher morbidity compared with nonsurgical treatment (odds ratio, 3.3; CI: 1.9 –5.6; P 0.001). After successful nonsurgical treatment, a malignant disease is detected in 1.2% (CI: 0.6 –1.7) and animportant benign disease in 0.7% (CI: 0.2–11.9) during follow-up. The risk of recurrence is 7.4% (CI: 3.7–11.1). Conclusions: The results of this review of mainly retrospective studies support the practice of nonsurgical treatment without interval appendectomy in patients with appendiceal abscess or phlegmon. (Ann Surg 2007;246: 741–748)

T

he inflammation in acute appendicitis may sometimes beenclosed by the patients own defense mechanisms, by the formation of an inflammatory phlegmon or a circumscribed abscess, often presenting some days after the onset of symptoms as a palpable mass. The management of these patients is controversial.1 Immediate appendectomy may be technically demanding because of the distorted anatomy and the difficulties to close the appendiceal stump because of theinflamed tissues. The exploration often ends up in an ileocaecal resection or a right-sided hemicolectomy due to the technical problems or a suspicion of malignancy because of the distorted tissues. The traditional management of these patients is nonsurgical treatment followed by interval appendectomy to prevent recurrence. The need for interval appendectomy after a successful nonsurgical treatment hasrecently been questioned as the risk of recurrence is relatively small.2–7 After successful nonsurgical treatment of an appendiceal mass, the true diagnosis is uncertain and an underlying diagnosis of cancer or Crohn’s disease may be delayed. Some authors therefore advocate immediate surgery with a rightsided hemicolectomy if needed, as the definitive treatment with acceptable morbidity.8 –12Recently, the conditions for conservative management of these patients has changed due to the development of computerized tomography (CT) and ultrasound (US), which has improved the diagnosis of enclosed inflammation and made drainage of intra-abdominal abscesses easier. New efficient antibiotics have also given new opportunities for nonsurgical treatment of appendicitis. This report aims at reviewing theresults of nonsurgical treatment of patients with enclosed appendiceal inflammation, with emphasis on the success rate, the need for drainage of abscesses, the risk of undetected serious disease, and the need for interval appendectomy to prevent recurrence.

From the *Department of Surgery, University Hospital, Linkoping, Sweden; ¨ †Department of Surgery, County Hospital Ryhov, Jonkoping,...