You are here: MEDICA Portal. Our Topics in 2009. Topic of the Month September: Intensive Medicine. Antibiotics.
Seek and You Will Find
Pretty, but very dangerous
Staphylococcus aureus means the "golden cluster seed". This rather beautiful translation decorates a nasty pyogenic organism that enjoys living on skin. Around 50 per cent of all humans carry the bacteria around with them - most of them not aware of being "colonised" since the germ does normally not cause any problems. It may only turn dangerous when the bacteria enters the body through, for example, a cut possibly causing a severe infection that needs to be treated with antibiotics.
However, by now 20 to 25 per cent of all Staphylococcus aureus contracted in hospitals are resistant against current antibiotics and therefore called MRSA (Methicillin-resistant Staphylococcus aureus). „These MRSA can only be fought by using expensive and often less well-tolerated antibiotics“, Herbert Hof explains. The scientist has until recently been the director of the Institute for Medical Microbiology and Hygiene at the University Hospital Mannheim. He adds that one day these antibiotics in reserve may not work anymore, too, since the bacteria keep evolving constantly.
MRSA infections most often occur in rest homes or in hospitals, especially in ICUs since germs have the possibility to enter the human body via the many tubes. Even though the good news is that the numbers of infections that are being reported voluntarily to the "German National Reference Centre for the Surveillance of Nosocomial Infections" have been constant for the past seven, the bad news is that it has not been possible to decrease them either.
The new obligation to inform only touches the tip of the iceberg
Therefore, an obligation to inform came into action on 1 July 2009. Medical laboratories since then have to inform local health authorities about positive MRSA findings in the blood or brain liquor of critically ill patients. „The more precise data on MRSA infections should provide us with a better overview on the problem and also help us to identify a cumulative occurrence of these bacteria as well as help us fight them more specifically“, Günther Dettweiler says, assistant press officer of the Robert Koch Institute in Berlin. In case of an alarmingly high number of MRSA infections in a hospital, experts from the local health authorities came in to check up on hygiene standards there.
„But this measure only touches the tip of the iceberg“, Hof criticises, „because the number of colonised patients without any symptoms is not being collected anywhere.“ Especially this group of people is important for effectively fighting MRSA since they are carriers of these multiresistant germs without knowing it. An easy way to detect the bacteria would be tissue samples such as a smear from the nose where the pathogens like to reside. Culturing the bacteria subsequently is a way to elucidate after a few days if the patient is a carrier of MRSA or not. PCR tests are quicker, delivering results after already one to two hours. But these tests are not being commonly used since they are more expensive than the cultivation procedure.
Prevention through screening
Dutch hospitals - on the contrary to Germany - rigorously test all new patients entering the hospital that exhibit a high risk of MRSA colonisation. People arriving from rest homes or other hospitals, for example. Or patients that have been to Germany before. Those testing positive on MRSA need to be isolated in single rooms with a subsequent special disinfecting treatment. That way the Dutch succeeded in pushing the portion of MRSA in hospitals down to less than five per cent.
„Such screenings are rarely undertaken in German hospitals since they put strain on the budget“, Hof explains. Costs for the tests and the subsequent isolation of positively tested patients as well as the more intensive care of MRSA infections. „Each patient contracting MRSA and falling ill will cost a clinic about 5,000 to 6,000 Euro. Culturing bacteria, on the other hand, costs about 10 Euros and a PCR test 25 Euros“, Hof adds. However, it is not just economical considerations that put screenings into favour: „Each hospital is ethically responsible for doing everything possible to reduce the risk of being threatened by such an infection as much as possible."