Rapid emergence of antibiotic resistance during standard therapy

First author Dr Leif Tüffers investigated the evolution of resistance in the pathogen Pseudomonas aeruginosa during antibiotic treatment in a cohort of cystic fibrosis patients. © Christian Urban, Kiel University

Antibiotic-resistant pathogens pose one of the greatest threats to public health worldwide. In the near future, harmless bacterial infections may no longer be treatable and may again become the most common non-natural cause of death.

At the same time, the available repertoire of antibacterial agents is becoming increasingly smaller as resistance rates rise. The basic mechanisms of resistance evolution, i.e. the adaptation of a disease germ to the mode of action of a drug, have been well researched experimentally. How such loss of drug susceptibility develops in individual patients in the course of standard antibiotic therapy has not yet been studied.

A research team from the department of Evolutionary Ecology and Genetics at Kiel University has now investigated the evolution of resistance in the pathogen Pseudomonas aeruginosa during antibiotic treatment in a cohort of cystic fibrosis patients as an example. For the first time, they researched to what extent resistance evolves during a single course of antibiotic therapy.

The researchers now found that resistance rapidly emerged in about one third of the patients. These findings were obtained within the Leibniz ScienceCampus “EvoLUNG” and the Cluster of Excellence “Precision Medicine in Chronic Inflammation” (PMI) and were recently published in the Journal of Antimicrobial Chemotherapy.

Cystic fibrosis lung infection as an example

In the study, the research team focused on a small cohort of cystic fibrosis patients. The disease, which is uncurable to date, is caused by impaired cellular water transport and leads to viscous body secretions and associated dysfunction of numerous organs. It affects the respiratory tract and lungs in particular. Frequent infections in adult patients are mainly caused by Pseudomonas. As a result, they have to be treated with antibiotics frequently or even permanently.

In order to assess whether resistance evolves in the course of a single standard treatment with two or more antibiotics, the scientists examined the bronchial secretions of the patients daily and isolated Pseudomonas bacteria. This enabled them to investigate how the bacteria adapted to therapy over a period of 14 days. “In every third patient the pathogen adapted surprisingly quickly to the administered drugs and antibiotic resistance evolved within one to three days,” summarised Dr Leif Tüffers, a researcher in the Department of Evolutionary Ecology and Genetics. “The rapid evolution of resistance mainly affected newly administered antibiotics from the betalactam drug class,” continued Tüffers.

Findings match evolutionary experiments

These findings were obtained in real time on patients during clinical routine therapy for the first time. They generally correspond well with experimental observations from previous laboratory experiments with the Pseudomonas pathogen. Although resistances evolve faster in the laboratory, sometimes within a few hours, the bacteria in the patient's body grow much more slowly. To date, it is not entirely clear how exactly bacteria in the patients achieve such rapid evolution of resistance to the betalactam antibiotics, including penicillin. “It is possible that this rapid adaptation to the drug occurs as a result of spontaneous, new mutations in resistance genes,” said Tüffers.

In current research within the Cluster of Excellence PMI, the scientists now investigate the clinical applicability of evolution-based treatment strategies, which proved successful under laboratory conditions in the past. “The processes of resistance evolution are often comparable, regardless of whether it is a laboratory experiment with a specific single bacterium or the treatment of a bacterial infection in patients,” said Professor Hinrich Schulenburg, head of the Department of Evolutionary Ecology and Genetics at Kiel University. “We therefore want to investigate in future studies to what extent, for example, the principle of collateral sensitivity, in which the formation of resistance to one antibiotic increases sensitivity to a second drug, can be used to treat lung infections,” continued Schulenburg.

Pictures are available for download:

https://www.uni-kiel.de/de/pressemitteilungen/2019/362-tueffers-jac-author.JPG
Caption: First author Dr Leif Tüffers investigated the evolution of resistance in the pathogen Pseudomonas aeruginosa during antibiotic treatment in a cohort of cystic fibrosis patients. © Christian Urban, Kiel University

https://www.uni-kiel.de/de/pressemitteilungen/2019/362-tueffers-jac-samples.JPG
Caption: The isolates of the pathogen obtained from the bronchial secretions of the patients are preserved at -80 °Celsius for further examination. © Christian Urban, Kiel University

https://www.uni-kiel.de/de/pressemitteilungen/2019/362-tueffers-jac-vortex.jpg
Caption: Using a so-called vortexer, the bacterial isolates are prepared for the analysis of their genetic information. © Christian Urban, Kiel University

More information:

Department of Evolutionary Ecology and Genetics,
Zoological Institute, Kiel University:
http://www.uni-kiel.de/zoologie/evoecogen

Leibniz ScienceCampus for Evolutionary Medicine of the Lung:
http://evolung.fz-borstel.de

Prof. Hinrich Schulenburg
Head of the Department of Evolutionary Ecology and Genetics,
Kiel University
Tel.: +49 (0) 431-880-4141
E-mail: hschulenburg@zoologie.uni-kiel.de

Dr Leif Tüffers
Department of Evolutionary Ecology and Genetics,
Zoological Institute, Kiel University
Tel.: +49 (0) 431-880-4145
E-mail: ltueffers@zoologie.uni-kiel.de

Original publications:
Leif Tueffers, Camilo Barbosa, Ingrid Bobis, Sabine Schubert, Marc Höppner, Malte Rühlemann, Andre Franke, Philip Rosenstiel, Anette Friedrichs, Annegret Krenz-Weinreich, Helmut Fickenscher, Burkhard Bewig, Stefan Schreiber and Hinrich Schulenburg (2019): Pseudomonas aeruginosa populations in the cystic fibrosis lung lose susceptibility to newly applied beta-lactams within 3 days.
Journal of Antimicrobial Chemotherapy
https://doi.org/10.1093/jac/dkz297

http://www.uni-kiel.de/zoologie/evoecogen
http://evolung.fz-borstel.de

Media Contact

Dr. Boris Pawlowski idw - Informationsdienst Wissenschaft

Alle Nachrichten aus der Kategorie: Health and Medicine

This subject area encompasses research and studies in the field of human medicine.

Among the wide-ranging list of topics covered here are anesthesiology, anatomy, surgery, human genetics, hygiene and environmental medicine, internal medicine, neurology, pharmacology, physiology, urology and dental medicine.

Zurück zur Startseite

Kommentare (0)

Schreib Kommentar

Neueste Beiträge

Alien species to increase by 36% worldwide by 2050

The number of alien (non-native) species, particularly insects, arthropods and birds, is expected to increase globally by 36% by the middle of this century, compared to 2005, finds new research…

Geothermal energy: Fraunhofer IEG operates simulator for drilling at depths up to 5,000 meters

To tap into geothermal reservoirs, boreholes must be drilled deeply into the earth’s crust. Due to the extreme pressures and temperatures involved, this is expensive and time consuming. A research…

Immune cells as guests in the tissue

Specialized immune cells settle permanently in tissues of the body and build “local task forces”. Wuerzburger scientists have recently discovered, how these cells can regenerate themselves and can adapt to…

By continuing to use the site, you agree to the use of cookies. more information

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this.

Close