Research for infection protection

Interview: “Resistant Gram-negative bacteria supersede MRSA as main problem-causing microorganism”

Prof. Dr. rer. nat. Paul-Michael Kaulfers, Head of Hospital Hygiene, University Medical Center Hamburg-Eppendorf, Germany
Prof. Dr. rer. nat. Paul-Michael Kaulfers, Head of Hospital Hygiene, University Medical Center Hamburg-Eppendorf, Germany

Three questions to Prof. Dr. rer. nat. Paul-Michael Kaulfers, Head of Hospital Hygiene, University Medical Center Hamburg-Eppendorf, Germany


Highly resistant bacterial pathogens are on the rise. What are the greatest risks?

Paul-Michael Kaulfers: While the MRSA incidence has remained relatively stable in our clinic with 0.4 to 0.5 MRSA cases per 100 patient-days, the number of resistant Gram-negative pathogens with extended-spectrum beta-lactamases (ESBLs) has increased strongly. Escherichia coli and Klebsiella pneumoniae are typical examples. Another problem is the occurrence of nonfermenters such as Pseudomonas and Acinetobacter species that exhibit resistance to carbapenems, which are considered as reserve agents.  


Your clinic was complimented on the management of EHEC, also an ESBL. What was the key to success?

Paul-Michael Kaulfers: During the EHEC epidemic until the end of June 2011, throughout Germany around 3 800 people acquired an infection, 53 died, In the UKE, we treated more than 1 500 patients with suspected EHEC, including almost 150 with HUS. In addition to good medical care, we implemented a strict hygiene protocol with isolation and protective clothing. For hand hygiene, we observed a very high compliance. Thus, we had no transmissions of the pathogen and all our environmental examinations were negative.


Do bacteria also become resistant to hand disinfectants when these preparations are used increasingly?


Paul-Michael Kaulfers:
At the UKE, we have delved into resistances to active ingredients in disinfectants intensively. There is no evidence that alcohol, the main active ingredient in common hand disinfectants, causes resistances. This can be explained by the alcohols’ mode of action. The more unspecific the mechanism of action, the lower the risk of the development of resistance. Alcohols have an unspecific mechanism of action: the alcohol molecules damage the outer cell membrane, penetrate the cytoplasm and destroy the inner structure of the cell molecules and of the cytoplasm’s proteins. This process (referred to as denaturation) leads to a loss of cellular activity and, finally, to the cell’s death.


Source:
Speech by Prof. Dr. rer. nat. Paul-Michael Kaulfers, Head of Hospital Hygiene, University Medical Center Hamburg-Eppendorf, Germany. Lunchtime Symposium: Hospital-acquired infection and hand hygiene: How research findings improve infection protection, Berlin, Germany, 9 November 2012, arranged by the BODE SCIENCE CENTER, Hamburg, Germany, scientific centre of excellence of PAUL HARTMANN AG, Heidenheim, Germany.