Changes in the intestinal flora after the administration of prophylactic antibiotics to patients undergoing a gastrectomy.
OBJECTIVE
Changes in the intestinal flora were investigated in patients administered antibiotics for 4 days after a gastrectomy.


METHODS
Twenty-four patients were divided into each of the following groups: cefazolin, 1 g every 8 h; cefozopran, 0.5 g every 8 h; flomoxef, 1 g every 8 h. All drugs were administered intravenously for a 4-day period.


RESULTS
Antibiotic prophylaxis caused no major change in the total number of anaerobes because of the preservation of the Bacteroides fragilis group. However, the number of Bifidobacterium, Lactobacillus, Eubacterium, and Veillonella spp. decreased by an average of 100-fold. These changes were accompanied by an overgrowth of Enterococcus spp. and Pseudomonas aeruginosa.


CONCLUSIONS
Four days of antibiotic prophylaxis after surgery caused a suppression of colonization resistance in the intestinal flora. Certain genera of anaerobes may thus play an important role in preventing overgrowth of antibiotic-resistant organisms after surgery. Surgeons should decide the duration of antibiotic use after carefully considering its influence on the intestinal flora.
First Department of Surgery, Hiroshima University School of Medicine, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan.
Yoshio
Y
Takesue
Takashi
T
Yokoyama
Shinji
S
Akagi
Hiroki
H
Ohge
Yuuji
Y
Imamura
Yoshiaki
Y
Murakami
Taijiro
T
Sueda
D000328:Adult; D000368:Aged; D019072:Antibiotic Prophylaxis; D001419:Bacteria; D002437:Cefazolin / Q000008:administration & dosage / Q000494:pharmacology*; D002511:Cephalosporins / Q000008:administration & dosage / Q000494:pharmacology*; D004064:Digestive System / Q000382:microbiology*; D004351:Drug Resistance; D005260:Female; D005743:Gastrectomy; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D011157:Population Dynamics; D011300:Preoperative Care; D000097586:Cefozopran
D002437:Cefazolin; D002511:Cephalosporins; D000097586:Cefozopran; C045693:flomoxef