28 February 2004

---Why Fleming Is Rolling In His Grave

The following data has just been noted among British hospitals:

Deaths due to Superbug: 15 in 1993 and 800 in 2002

Cases due to Superbug: 210 in 1993 and 5309 in 2002

The Superbug discussed here is the methicillin-resistant staphylococcus aureus (MRSA). MRSA infections can lead to death, predominantly in hospitalized, debilitated patients. Methicillin is a penicillinase-resistant penicillin, meaning it is already an improved version of penicillin, one that is used against bugs that has penicillinase which is an enzyme produced by certain bacteria that inactivates penicillin and results in resistance.

"In 1940, Fleming discovered penicillin and this dramatically reduced the incidence of bacterial infections around the world. This single antibiotic was effective against a broad spectrum of bacteria for years, until S. aureus developed the ability to produce beta-lactamase, an enzyme that destroys penicillin. These mutations confer S. aureus with a remarkable ability to adapt to changing antibiotic environments. The resiliency of S. aureus motivated pharmacologists to create a class of semi-synthetic penicillins that could withstand beta-lactamase. These antibiotics became known as beta-lactam penicillins, with METHICILLIN as the prototype. For years, infections with S. aureus were reliably eradicated with methicillin and its analogs, nafcillin and cloxacillin. However, the resourceful bacterium soon became able to resist these beta-lactam antibiotics, and the first strain of MRSA was identified in 1961. Since the mid-1980s, antibiotic resistance among nosocomial (hospital-acquired) S. aureus isolates has been increasing appreciably" (from the Archives of Internal Medicine, 162, 2229-2235, 2002).

Superbug is 'super' in the sense that it is able to adapt by mutation to the current generations of antibiotics and penicillins, making it resistant to the said medications and able to inflict more harm.

Aside from the natural resiliency of the bugs, part of the mutation is caused by the manner of antibiotic prescription being given to patients.

Here in the Philippines, I have yet to meet a colleague who prescribes penicillin on the first sign of infection in a patient, even if its just a mild infection. Most doctors go for the big guns like the cephalosporins and quinolones. Cephalosporins come in four generations, with the fourth being the strongest, and nowadays, fellow doctors prescribe not the first, but already the second generation as the starting antibiotic, even for a mild complaint like fever and colds.

Sometimes its a culture thing. Some doctors fear that patients will prefer them if they prescribe medicines which are strong and sure to end the infection in a couple of days. Some patients prefer doctors who prescribe medicines they haven't heard of, and doctors sometimes succumb to this unspoken pressure.

In so doing, resilient bugs adapt to the gamut of strong antibiotics by mutating and becoming resistant. So the next time I prescribe amoxicillin to a patient, I notice non-improvement. Why? Because he is probably infected with a resistant bug. And so, I am forced to give a stronger antibiotic. And the cycle goes on with both patient and doctor emerging as losers, and the superbug as winner.

Of course, there are also side issues like the food we eat. There were reports in the past that the meat and poultry (dairy products included) we consume are laden with antibiotics also, further contributing to superbug resistance. Antibiotics are administered routinely to cattle and poultry before they are slaughtered for consumption. We ingest these antibiotics of course, when we eat hamburgers or chickenjoys or scrambled eggs. Although in minute amounts, reports say these are also enough to stimulate the bugs to mutate and become resistant.

The picture gets murkier in a hospital setting. With the variety of cases being handled in a hospital, it is almost a certainty that a whole lot of bugs, resistant or otherwise, are present there. Add to this the fact that antibiotics given here are more potent and almost always administered intravenously. The result? Powerful superbugs, indeed.

What can be done?

In my practice, unless it is very, very necessary, I DO NOT prescribe antibiotics. I tell the patients what to do supportively (bed rest, lots of juices, wash hands frequently, etc.) and that's about it. Patients who recover without the aid of antibiotics become tougher against infections whether these are superbugs or not. Nothing beats good old immunity. I also try to encourage colleagues not to fall into the trap of prescribing antibiotics wantonly. I can vouch that my close physician friends do the same thing I do.

But we are but a speck in this war. We fight the Superbug. We fight the profit-oriented antibiotic industry and the temptations they lay before us.

I hope we win. Please root for us.

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