Effect of Preventive Administration of a Nonpathogenic <i>Escherichia coli</i> Strain on the Colonization of the Intestine with Microbial Pathogens in Newborn Infants

TLDR

In a randomized, double‑blind trial, 27 newborns received daily oral inoculations of 1 ml containing 10⁸ cells of nonpathogenic E. coli Nissle 1917 for the first five days, while 27 controls received placebo; stool samples were collected on days 1, 2, 3, 5, 21, and 6 months and tested for the strain and for pathogenic bacteria.

Abstract

In a randomized, double-blind study, 27 healthy newborn infants were colonized with the nonpathogenic <i>Escherichia coli</i> strain Nissle 1917 (E. <i>coli</i> DSM 6601, Mutaflor®) during the first 5 days of life by daily oral inoculation of 1 ml of a suspension with 108 living cells. A second group of 27 newborns, used as controls, received a placebo suspension (1 ml of phosphate-buffered saline) instead. Stool samples were taken on days 1,2, 3, 5, and 21, and 6 months after birth. All samples were examined for the presence of the nonpathogenic E. <i>coli</i> strain and of pathogenic and potentially pathogenic microorganisms. The administered E. <i>coli</i> strain was detected in the stools of the colonized newborns from day 2 and remained present throughout the study in more than 90% of these infants. Colonization with true and potential bacterial pathogens was significantly reduced in infants receiving <i>E.</i><i>coli</i> strain Nissle 1917 compared to the placebo group – both with respect to numbers of pathogens and to the spectrum of species.