Imipenem therapy for perforated and gangrenous appendicitis.

A matched patient control study of imipenem therapy of patients with perforated or gangrenous appendicitis was performed. Thirty-three patients treated with imipenem and cilastatin were compared with 66 control patients treated with clindamycin and gentamicin. Patients were matched for age and surgical pathologic factors. Twenty-five of the 33 imipenem treated patients had perforated (two with abscesses) and nine had gangrenous appendicitis. Anaerobes were recovered from 23 of 32 (72 per cent), anerobes from 31 of 32 (97 per cent) and Pseudomonas from six (26 per cent) of the 23 with perforated appendicitis. Only one isolate, a Fusobacterium species was resistant to imipenem. Enterococci were isolated only from three imipenem treated patients, all were susceptible and were not associated with failures. Frequency of other pathogens isolated was similar for the imipenem and clindamycin and gentamicin patients. One failure occurred in the imipenem treatment group. Failures and adverse reactions were not different for the two groups. The study would have detected as significant (p equals 0.03) a 9 per cent difference in failure rates. Mean days of fever of more than 38 degrees C and days of hospitalization were fewer (p less than 0.05) for imipenem treated patients even when only patients with perforated appendicitis were compared. Days to return of intestinal function were fewer for control patients. Imipenem and cliastatin appeared to be an effective antimicrobial agent used as an adjunct to surgical treatment for peritonitis associated with appendicitis even when caused by Bacteroides fragilis group organisms or Pseudomonas species, or both.