Comparison of therapeutic effectiveness of percutaneous drainage with antibiotics versus antibiotics alone in the treatment of periappendiceal abscess: is appendectomy always necessary after perforation of appendix?

BACKGROUND

The present study was designed to compare the therapeutic effectiveness of percutaneous drainage with antibiotics versus antibiotics alone in the treatment of appendicitis complicated by periappendiceal abscess.

METHODS

In a prospective study, 50 patients with acute appendicitis complicated by periappendiceal abscess > or = 3 cm in size were randomly assigned to two groups. The first group received treatment with ultrasound guided-percutaneous drainage and i.v. antibiotics (ampicillin, cefuroxime, and metronidazole), and the other group received antibiotics only. Patient's baseline characteristics, duration of hospital stay, and treatment outcome and complications were analyzed.

RESULTS

Appendectomy was avoided in 16/25 patients in the drainage group and 2/25 patients in the non-drainage group during follow-up with RR of 0.39 (95% CI = 0.22-0.62; p < 0.05). One patient in the drainage group and 8 patients in the non-drainage group underwent surgery in the first month after the beginning of treatment. Eight patients in the drainage group and 15 in the non-drainage group underwent interval appendectomy. There was no statistically significant difference between the two groups regarding patient demographics, abscess size, and pretreatment clinical symptoms. Hospital stay up to the subsidence of clinical and sonographic signs was significantly shorter (p < 0.001) in the drainage group, with a mean difference of 6.4 days (95% CI = 5.0-7.9; p < 0.05).

CONCLUSIONS

Percutaneous drainage with antibiotics is a safe and effective way of treating acute perforated appendicitis. The recurrence rate for these patients is relatively low, and very often interval appendectomy is not required. For patients with periappendiceal abscess > or = 3 cm in diameter, antibiotic therapy alone is insufficient and the recurrence rate is high.