The effect of FCE 22891, a new oral penem, on faecal flora anaerobes and their fermentation end products in patients with chronic obstructive pulmonary disease.

The influence of FCE 22891 on the faecal flora was investigated in 11 patients with an acute exacerbation of chronic obstructive pulmonary disease (COPD). Colony counts of faecal (an)aerobes and concentrations of their short-chain fatty acids and organic acids were determined simultaneously in fresh faeces before, during and after administration of the drug, and compared to those of healthy human volunteers. The MIC of FCE 22891 for the 142 isolated anaerobes was determined, and compared to the biologically active concentration of the drug in faeces. The Bacteroides colony counts of the patients increased significantly by day 9 compared to day 3, but were significantly lower than those of the healthy controls before, during and after the study. Significant changes in short-chain fatty acids and organic acid concentrations occurred in faeces of the patients during and after treatment, and especially when compared to healthy controls. A strong increase in MICs during treatment was found in Clostridium species, other than Clostridium difficile. FCE 22891 had only a moderate effect on the composition of the anaerobic faecal flora, but bacterial fermentation was mainly disturbed before and early on in treatment, which could have been caused by the disease.