Systemic metronidazole combined with either topical povidone-iodine or ampicillin in acute appendicitis.

One-hundred consecutive patients undergoing appendicectomy either electively or for clinically diagnosed acute appendicitis were studied to examine the difference between the use of topical povidone-iodine (PVP-I) and ampicillin in the wound given at the time of closure. All patients were treated with metronidazole suppositories for 48 h starting at the time of pre-medication in addition to a topical agent. The overall wound infection rate was 14%. If the appendix was histologically normal or inflamed, the rate fell to 10% whereas if gangrenous or perforated it rose to 24%. Sixty-six per cent of the patients with a perforated appendicitis developed a wound infection. There was no significant difference in the wound infection rate between those treated with PVP-I and those with ampicillin. Topical antisepsis using PVP-I is preferable to ampicillin as it abolishes the risk of antibiotic resistance or allergy developing and since it is comparatively more cost-effective.