Value of cultures of tissue samples taken at operation for lower intestinal perforation.

Tissue cultures from perforations of the lower intestinal tract commonly yield both aerobes (coliform organisms) and anaerobes (Bacteroides sp. and Clostridium sp.). To determine the consistency of this pattern and the value of intraoperative cultures, the authors reviewed the hospital records of 115 patients with perforation of the appendix (100 patients) or colon (15 patients), treated between 1987 and 1990, in whom organisms were cultured from tissue samples taken intraoperatively. Attention was paid to the organisms cultured, their distribution and antibiotic sensitivity in initial samples and in subsequent samples obtained when there were septic complications. On average, 4.7 bacterial isolates per patient were obtained. The common organisms were as expected: Bacteroides fragilis, Escherichia coli and Clostridium sp. Although the culture results did not affect the management of these patients, the sensitivity of Bacteroides fragilis to cefoxitin was found to be lower than expected, indicating a shift in sensitivity.