Small-bowel transplant patients with an ileostomy which is supposed to be an opening into their small bowel apparently have a very dissimilar population of bacteria existing in their gut as opposed to patients whose ileostomy has been closed. This is claimed by a research conducted in the UC Davis and Georgetown University Medical Center.
By analyzing the bacterial DNA, the research team discovered that in ileostomy patients, the gut bacteria were claimed to be mostly Lactobaccilli and Enterobacteria, groups that may utilize oxygen in their metabolism. In patients whose ileostomies had been closed, the bacterial populations may mostly consist of Bacteroides and Clostridia, bacteria to which oxygen may be lethal.
Patients who undergo a small-bowel transplant generally have a minute opening, or ileostomy, left to the outside so that doctors could observe the transplant for any indication of rejection. In this research, the experts could apparently follow changes in the gut bacteria of about 17 transplant patients for about two years by taking periodic samples from the small bowel through the ileostomy opening.
Jonathan Eisen, UC Davis Professor, commented, “ This project represented a very unique opportunity to study the recolonization of the ileum, or small bowel, after a disturbance — transplantation — much like studying regrowth of a forest after clearcutting.”
The researchers performed DNA analysis that apparently concentrated on a specific gene, for ribosomal DNA that may be there in all species of bacteria but supposedly differs in small ways among species. By means of both DNA sequencing and quantitative polymerase chain reaction analysis of this gene, the researchers could supposedly gauge the comparative proportions of different kinds of bacteria.
Among ileostomy patients, the population appeared to be somewhat steady over time and was apparently subjugated by bacteria that are ‘facultative anaerobes’ i.e. the bacteria which may use oxygen, but don’t need it.
In 10 patients, the ileostomy was shut in due course. Samples taken from some of these patients by colonoscopy apparently displayed that in severely anaerobic bacterial populations, oxygen may be lethal to them. This anaerobic mix of bacteria is said to be like that of a usual human bowel.
The outcome demonstrates that the gut may have two diverse, steady bacterial ecosystems. Usually, the gut may be low in oxygen. When oxygen may enter through an ileostomy, the population apparently transfers to a different but unwavering ecosystem. Neither kind of bacterial population appeared to be connected with any particular damage to the patient. But, a sudden change in population could be related to severe illness.
This research was published in the Proceedings of the National Academy of Sciences.