Studies with temocillin in the hamster model of antibiotic-associated colitis

The studies reported here were designed to ascertain whether or not the new beta-lactam antibiotic, temocillin, would produce antibiotic-associated colitis in the hamster. The experiments were controlled with clindamycin and cefoxitin, which are known to induce antibiotic-associated colitis experimentally and clinically. All three antibiotics were administered to groups of animals both parenterally and orally. Clindamycin, at 1 mg/hamster, caused a slow onset of antibiotic-associated colitis by both routes, with death occurring at between 4 and 8 days. 80 to 100% of the animals had diarrhoea and showed signs of haemorrhage and caecal distension, with the caecal contents being Clostridium difficile toxin-positive. The onset of antibiotic-associated colitis after administration of cefoxitin was less marked at the 1 mg parenteral dose, with only 40% of the hamsters showing signs of colitis. At the higher doses of cefoxitin, colitis was more severe and the animals exhibited dramatic weight loss, with death occurring at between 3 and 5 days. The majority of animals had diarrhoea and were C. difficile toxin-positive; 60 to 80% also showed signs of haemorrhage and caecal distension. In contrast, the hamsters receiving temocillin remained healthy with no signs of diarrhoea, and showed consistent weight gain. No pathological abnormalities were observed and the caecal contents were toxin-negative. These results suggest that temocillin therapy in humans is unlikely to cause significant disturbance of the gastrointestinal flora.