Treatments for urinary infections leave bacteria bald, happy and vulnerable
Treatment of Urinary Tract Infections
A different approach to treating urinary tract infections (UTIs) could defeat the bacteria that cause the infections without directly killing them, a strategy that could help slow the growth of antibiotic-resistant infections.
Instead of trying to wipe out bacteria, researchers in the laboratory of Scott Hultgren, Ph.D., the Helen L. Stoever Professor of Molecular Microbiology at Washington University School of Medicine in St. Louis, have been working to create pharmaceuticals that essentially "defang" the bacteria by preventing them from assembling pili, microscopic hairs that both enable the invasion of host cells and allow the bacteria to mount a cooperative defense against the host's immune system.
"We're leaving the bacteria bald but healthy and happy," says Jerome S. Pinkner, lab manager for Hultgren. "Rather than trying to kill them, we're working to make them non-pathogenic, so that they will be unable to adhere to or invade the bladder tissues and are readily eliminated from the body."
Pinkner and his colleagues think the bacteria will find it harder to evolve resistance to a treatment that does not directly impact their survival. According to an April 2006 National Institute of Allergy and Infectious Diseases fact sheet, resistance to at least one antibiotic has been detected in more than 70 percent of the bacteria that cause hospital-acquired infections.
In a recent paper in the Proceedings of the National Academy of Sciences, the Hultgren group and its collaborators reported on the successful development of a second generation of anti-pilus treatments or pilicides. A third generation is already undergoing tests now, and researchers are hoping to begin tests of their most potent pilicides in animal models in about a year.
Urinary tract infections mainly occur in women and are one of the most common infections, causing around $1.6 billion in medical expenses every year in the United States. Scientists believe 90 percent of all UTIs, which have been linked to poor hygiene, sexual behavior, and migration of intestinal flora, are caused by the bacterium Escherichia coli (E. coli).
Half of all women will experience a