MONDAY, Sept. 30, 2002 (HealthDayNews) -- Doctors are over-prescribing Cipro and its kin when more modest treatments would be equally effective, and in the process they're exacerbating the problem of drug-resistant germs.
So say U.S. researchers who found that roughly a third of pneumonia patients are discharged from the hospital with orders for Cipro and other fluoroquinolone antibiotics, even when the strain of lung bacteria they have would succumb to penicillin-like drugs.
Ironically, the overuse doesn't appear to be making Streptococcus pneumoniae, a major cause of pneumonia, tougher to treat. But the researchers say it is having a major impact on the hardiness of several unrelated bugs, including E. coli and Pseudomonas aeruginosa, a common source of respiratory infections in people with cystic fibrosis.
At the University of California-San Francisco Medical Center, for example, the incidence of fluoroquinolone susceptible E. coli linked to bladder infections plunged from 98 percent in 1997 to 79 percent last year. "That's an enormous drop," said Joseph Guglielmo, director of the hospital's antimicrobial review program and a member of the study team.
Similarly, the share of Pseudomonas aeruginosa strains that resist the drugs climbed from just 5 percent to roughly 40 percent between 1992 and 2001. These trends hold true in other parts of the United States, too, added Guglielmo. He presented the study this weekend at the annual meeting of the Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) in San Diego.
The study analyzed treatment of more than 13,000 Americans in the hospital for pneumonia they'd picked up in the community. For most people, the strain of germ causing their infection wasn't identified. In these cases, prescribing fluoroquinolones is appropriate, the researchers said.
But in the group with successful lab tests to identify the offending organism, between 30 percent and 35 percent were sent home with a fluoroquinolone drug even though the strain of bacteria they had would have responded well to penicillin.
Dr. Dale Bratzler, principal clinical coordinator of the Oklahoma Foundation for Medical Quality in Oklahoma City, who helped conduct the study, said in these cases doctors should know better. He said specialty group guidelines support the notion of "empiric" therapy -- doing what you know will work in the absence of more evidence in cases where the cause of pneumonia is a mystery.
"But once you do know what the organism is, you should switch them to the narrowest effective drug," he said. That, he added, clearly isn't happening as often as it should.
Dr. Peter Houck, of the Centers for Medicare and Medicaid Services in Seattle and a collaborator on the research project, said there are reasons doctors choose so-called "broad spectrum" drugs like fluoroquinolones that kill a wide range of bacteria. They can be taken once a day, compared with up to four times a day for narrower-acting compounds like penicillin and amoxicillin. That's more convenient for patients. And while Cipro and its relatives are more expensive per tablet than those other drugs, it may be cheaper in the long run because administration costs are lower.
Still, Houck said, those reasons ultimately fall short. "Why use the big gun [when you don't have to], particularly when we're so concerned about the emergence of drug resistance?"
What To Do
For more on fluoroquinolones, try MEDLINEplus. For more on the problem of drug resistance, visit the World Health Organization.
