MEDICAL SURFARI: WHAT TO DO WHEN ANTIBIOTICS DON'T WORK

It is hard to imagine that just a little more than 50 years ago most people knew nothing of antibiotic medications and now almost everyone, including children, know that antibiotics are medicines used to treat bacterial infections. These medications range from treatments for strep throat, pneumonia, acne to meningitis and tuberculosis. Antibiotics are medications that have been designed to kill or harm bacteria, but they do not treat viruses.

Bacteria are remarkably adaptive to their environment and that may include an environment of antibiotics. These single celled organisms contain genes that create these adaptations. These are survival adaptations and bacteria quickly discover that antibiotics are harmful to them. Consequently some bacteria develop or call upon already developed resistance genes to create a mechanism to defeat the antibiotic. Bacteria can acquire these genes for resistance in three ways. They may develop a spontaneous gene mutation change in DNA that results in antibiotic resistance or they may transfer resistance genes to another bacteria in a form of microbial sects called transformation. Thirdly, one of the most frightening ways is by acquiring a gene from a small circle of DNA called a plasmid. Plasmids can transfer resistance genes among many, many different types of bacteria. Plasmids were the cause of the diarrhea epidemic in Guatemala in 1968 that killed 12,500 people. The bacteria responsible for this epidemic was resistant to four antibiotics.

Our world is now beginning to see the threat of incurable bacterial infections that could lead to an international public health nightmare. We already have some bacterial species that are capable of causing life-threatening illness and that resist every clinically available antibiotic in the physician's armamentarium.

The problem of antibiotic resistance is an exceedingly complex one that does not have a simple solution. When antibiotics are used in a preventative way or when they are used in too high of doses or for too long, they may kill off normal bacteria that would otherwise "crowd out" the life-threatening antibiotic-resistant bacteria. Other factors that have contributed to this problem include the broad preventative use of antibiotics in livestock farming and agriculture. Even jet travel plays a role in this as this has allowed the organisms like antibiotic-resistant tuberculosis to be spread to many different parts of the world. Reversal of antibiotic-resistant bacteria requires a new awareness of the broad consequences of antibiotic use. We must learn to accept that some bacteria are normal beneficial components of our world and we must make decisions about our use of antibiotics that will preserve these normal bacteria that resist the overrun of resistant bacterial strains. This will surely require the cooperation among many countries around the globe to educate their populations about the impact of improper antibiotic use and resultant antibiotic-resistant bacteria. Remember, antibiotics save lives. Take them wisely---don't take them for granted.

WORLD WIDE WEB RESOURCES

Scientific American

www.sciam.com/1998/0398issue/0398levy.html

This web page provides a reprint of a recent very informative article in the Scientific American entitled "The Challenge of Antibiotic Resistance".

Resistance Web Resistance

web.mfhs.edu/cit/Index.asp

The purpose of Resistance Web is to share timely, useful data on bacterial resistance with clinicians and researchers, to assist in the process of resistance awareness.

Dr. Scott Gibbs is a Cape Girardeau neurosurgeon and editor-in-chief of Mosby's Medical Surfari. You may e-mail questions to him at drgibbs@semissourian.com or write in care of the Southeast Missourian, P.O. Box 699, Cape Girardeau, Mo., 63701.