Thursday, September 20, 2007

Antibiotic Resistance is on an "Alarming" Rise

Microbes develop fast, and changes can take place in them over a short period of time compared to other species of life on Planet Earth. When less than a decade ago, scientists first noticed an antibiotic resistant gene in bacteria taken from East Coast patients, they had no idea that the gene would be passed along so quickly to other strains of bacteria, and that it could actually be tracked as it marched across America.

Scientists found that this bacteria with an active copy of the gene could defeat carbapenems, a relatively young family of antibiotics that works on a wide variety of bacteria. Physicians generally reserve carbapenems for use in the most critically ill patients. That's why it is so distressing to doctors to find this gene popping up in more and more hospitals as it moves westward.

This new study, recently presented in Chicago at the Interscience Conference on Antimicrobial Agents and Chemotherapy is among the first to detect the resistance gene in samples taken from a Midwestern hospital.

Researchers found the gene in only four of 243 samples from 223 patients with bloodstream-based bacterial infections. But this gene, known as "BlaKPC" spreads easily among bacteria, and scientists found the method most hospitals use to check for resistance genes didn't detect all BlaKPC-positive strains.

It requires a very sophisticated high-tech method to detect this gene, something that most hospitals don't have. And detecting it in advance is necessary to save lives of those critically-ill patients whose lives could be threatened while in the hospital for other illnesses. To help slow the spread of this gene, scientists need to look at whether they can develop a more effective way to detect it using widely available equipment and procedures. In other words, something "low tech" that hospitals might already have or acquire easily.

This resistance gene was originally identified during an East Coast outbreak of the bacterium Klebsiella pneumoniae. What makes it so dangerous is that the gene can be easily copied and passed around not just among bacteria of the same species but also from one bacterial species to another. Subsequent studies found mortality rates climbing as high as 50 percent when bacteria with the resistance gene infected patients.

Many people believe that antibiotic resistance began when doctors would too easily prescribe broad-spectrum antibiotics to their patients. Others believe that this problem originates because of the many different consumer products such as soaps, kitchen products, etc, which have "anti-microbial" components. Regardless of the cause, it is a growing problem that we all need to contend with. See the excellent Wikipedia article linked to the headline of this post.


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