under the microscope
By Paul J . Pearce , PhD
Predators Within the Microbial Jungle : The Deadly Rise of Drug-Resistant Bacteria
Discovery of antimicrobials in the past century represented one of the most important advances in public health . Unfortunately , the massive use of these compounds in medicine and many other human activities has promoted the selection of pathogens that are resistant to one or several antibiotics . The current antibiotic crisis is creating an urgent need for research into new biological weapons with the ability to kill these superbugs .
A year ago , Frank Wills had taken his good health for granted . Forty years old , lean and fit , he was a recently divorced accountant living with his mother while he tried to put his life together again . Wills had been feeling weak and tired when he went to his doctor for a checkup . He told his doctor he ’ d been having stomach pains and chronic colds . A routine blood test revealed that he was suffering from leukemia . Although
The current antibiotic crisis is creating an urgent need for research into new biological weapons with the ability to kill these superbugs .”
Wills was shocked and frightened by his cancer diagnosis , his doctor explained that most forms of leukemia responded well to chemotherapy . Most probably , Wills would be able to undergo the chemotherapy regimen and soon resume a normal life .
That was the beginning of the end . Wills ’ oncologist initiated chemotherapy almost immediately . While often effective against leukemia and other cancers , the drastic treatment – with its toxic chemicals that course through the body like drain cleaner – can have the undesired effect of suppressing the immune system as well , frequently leading to bacterial infections that the weakened immune system cannot control . Antibiotics are used to help eradicate potentially life-threatening infections . Sometimes these bugs prove to be resistant to the initial antibiotic , in which case the doctor simply switches to another one . But for Wills , the antibiotic reserve had been exhausted .
Wills ’ infection was caused by the bacterium known as Enterococcus faecium , a Gram-positive coccus that is routinely found in the patient ’ s intestinal tract .
One expert calls E . faecium the cockroach of microbial pathogens : proliferating freely in the intestinal tract , it usually causes no more trouble than roaches colonizing a cupboard . But when breakdowns in the immune system allow the bugs to escape , they begin to cause serious infections , anywhere from the heart down to the urinary tract . After proving resistance to the initial antibiotics used , Wills ’ Enterococcus faecium also showed resistance to vancomycin , an older but still powerful antibiotic that represented the last-chance treatment for resistant
enterococci when all else failed . This time vancomycin also failed ; vancomycin-resistant Enterococcus faecium had appeared in Wills ’ bloodstream , a dangerous escalation .
Wills recovered from the VRE infection , and his leukemia went into remission . He slowly regained his strength and was able to return to his normal life for a year . After that year his leukemia returned , as did his Enterococcus faecalis . Chemotherapy was once again discontinued , and with rest and supportive care , Wills ’ better health returned – for another nine months . The bug that had been Wills ’ companion once again infected his bloodstream . Back came the high fever , the chills and irregular heartbeat , the shortness of breath . But this time there was no rebound , even when the chemotherapy was halted . Wills began vomiting , and his blood pressure plunged . As the flow of blood to his brain slowed to a trickle , his vision dimmed , and he became disoriented . At the same time , his ever-weakening heart pumped less and less blood to his other vital organs . One by one they began shutting down , like lights in neighbors during power blackouts . As the kidneys and liver stopped working and cleansing his body of waste material , Wills , in effect , poisoned himself . Finally came full blown septic shock . Wills went pale and delirious , cold and clammy to the touch . He suffered a series of small heart attacks and began to suffocate as his lungs filled with fluid . Ten days after VRE infected his bloodstream a final time , Wills died at the age of 43 .
For the past several years , a grim new era of multidrug-resistant bacteria is unfolding in the global healthcare system , making Wills ’ case seem all too typical . Unchecked , these hardy , virulent , and invisible bugs are proliferating all around us , some festering on bedrails and seat cushions , telephones , thermometers and computers , while others passing through the air from one human host to the next . Silently , they colonize even the healthiest of us , coating our skin , invading our noses , spreading to our throats , swimming through our stomachs and gastrointestinal tracts – until it can now be said that any of us is ever without at least some highly drug-resistant bugs , waiting for the chance to infect those among us who grew suddenly weak and sick .
These predators within the microbial jungle are everywhere , rapidly multiplying . And with each passing year , fewer drugs are available to stop them .
Paul J . Pearce , PhD , is principal of The Pearce Foundation for Scientific Endeavor .
References :
Pearce PJ . 2002 . Personal communication . 2002 . Shnayerson M and Plotkin M . 2002 . The Killers Within – The Deadly Rise of
Drug Resistant Bacteria .