New Multidrug Resistant Strain of Escherichia coli Has Emerged.

2001 OCT 25 - (NewsRx.com & NewsRx.net) -- A new strain of Escherichia coli bacteria accounted for 38% to 50% of the drug-resistant forms of urinary tract infections in women from three distinct regions in the United States, according to a new study by researchers at the University of California, Berkeley.

In the study, published in the October 4, 2001, issue of the New England Journal of Medicine, researchers analyzed the records of female students at UC Berkeley, the University of Minnesota, and the University of Michigan. The women had come into university health centers for treatment of urinary tract infections, or UTIs.

The fact that the bacteria emerged in different parts of the country suggests that the source of the strain may have been introduced through contaminated foods, said Lee Riley, MD, professor of epidemiology and infectious diseases at UC Berkeley, and principal investigator of the study.

"Urinary tract infections are not considered epidemic infections," said Riley. "The only way this (community-acquired infection) could happen is if it's spread by a contaminated product."

A bladder infection, or cystitis, occurs when bacteria such as E. coli get into the urethra, or urinary canal. People with bladder infections often experience frequent and painful urination.

Bacteria was isolated from more than 300 urine samples and tested for resistance to different antibiotics commonly used to treat bladder infections.

The study found that 22% of the E. coli strains collected from the UC Berkeley site were resistant to trimethoprim-sulfamethoxazole, a first-line antibiotic used to treat bladder infections. Further tests revealed that 38% to 50% of the drug-resistant forms of cystitis from these three geographical regions were caused by a previously unrecognized strain of multidrug-resistant E. coli called clonal group A.