Can Oral Metronidazole Substitute Parenteral Drug Therapy in Acute Appendicitis?: A New Policy in the Management of Simple or Complicated Appendicitis with Localized Peritonitis: A Randomized Controlled Clinical Trial

To demonstrate the efficacy of oral metronidazole (OM) in simple or complicated appendicitis with localized peritonitis, a randomized prospective study was carried out in 1083 patients, ranging in age from 4 to 50 years (mean age, 21.38).

The patients were randomly divided into two groups. The study group (SG) (524 patients) received OM (500 mg for adults, 7–10 mg/kg if less than 15 years) 2–3 hours before operation. The drug was continued 4 to 5 hours after operation, every 8 hours, for three doses if the appendix was mild to severely inflamed. In the case of complicated appendicitis (114 patients), the same dose was given for 3 to 6 days, depending on the absence or presence of pus. Ceftizoxime was administered to the control group (CG) (559 patients) 2 to 3 hours before operation and then postoperatively every 6 hours for three doses if the appendix was mild to severely inflamed. The complicated cases in the CG (120 patients) received a combination of penicillin, chloramphenicol, and gentamicin for 3 to 6 days, depending on the absence or presence of pus.

The serum concentration of metronidazole measured in 43 patients was at bactericidal level in 40 (mean ± SD standard deviation, 10.65 ± 4.89 μg/mL).

The rate of wound infection was not significantly different in the SG and the CG with the same degree of pathology (3.17% vs 2.96% if uncomplicated; 15.78% vs 14.16% if complicated, respectively). Pelvic collection occurred in four adults and one child in the CG with perforated appendicitis (4.16%). The same complication developed in two adults and two children in the SG with perforated appendicitis (3.5%). All six adults and one of the children in the SG had to be re-explored, whereas the remaining two children responded to conservative management (OM and gentamicin). In uncomplicated cases, hospital stay and hospital charge were both almost the same in both groups. However, length of hospitalization was nearly 1 day shorter and hospital cost per day was about 30 per cent less in complicated cases in the SG as compared with the CG.

Conclusively, OM may not only substitute parenteral antibiotics in acute appendicitis as a prophylactic agent, but it may also be used as a cost-effective drug and is more convenient to the patient.