[Early administration of antibiotic susceptible strain of Escherichia coli in the intestine of the premature infant]

An antibiotic-susceptible, innocuous Escherichia coli strain of human origin was administered to premature infants in order to protect them from nosocomial colonization by antibiotic-resistant enteric organisms. The strain was given to 16 untreated patients in the first six hours of life, and to 11 patients treated with antibiotics in the first six hours after cessation of treatment. The strain was able to colonize the intestinal tracts of all treated infants and 14/16 untreated infants. Colonization of these patients by antibiotic-resistant enteric organisms was compared with results obtained in a control group of 15 unadministered and untreated infants. A significant difference was recorded in the first ten days after administration. Our results show that previous antibiotic treatments did not impair intestinal colonization by an antibiotic-susceptible strain, and demonstrate the in vivo antagonistic abilities of the administered strain. Such antagonistic strains might thus be used for control of nosocomial infections of intestinal origin due to antibiotic-resistant enteric organisms.