MRGN
MRGN is used in medicine abbreviation for m ulti r esistente g ram n egative bacteria .
background
In the last few decades, doctors focused on multi - resistant gram-positive bacteria (keywords MRSA or VRE) as the cause of nosocomial infections ("hospital infections "). Since the end of the 20th century, this has also applied to some gram-negative bacteria. However, the multidrug resistance is to them by a variety of resistance genes or enzymes caused (eg. B. keywords as ESBL or NDM), so that a new definition appropriate is not available to resistance mechanisms in the foreground when, but against which clinically important groups of antibiotics , the Bacteria are resistant .
definition
The definition of multi-resistant gram-negative rod bacteria (MRGN) was carried out by the Commission for Hospital Hygiene and Infection Prevention (KRINKO) set up at the Robert Koch Institute (RKI ) and was published in 2012. Four groups of antibiotics were defined which are used clinically in the event of a severe infection with gram-negative bacteria (both members of the enterobacteria and so-called nonfermenters ).
The abbreviation MRGN is usually preceded by a number from two to four, which denotes the number of antibiotic classes - acylureidopenicillins , third and / or fourth generation cephalosporins , carbapenems or fluoroquinolones ( gyrase inhibitors ) - to which the respective bacterium is resistant . Since resistance to one or two classes of antibiotics is very common, but not critical, these abbreviations are rarely seen, and these bacteria are also not considered to be multi-resistant. In everyday clinical practice, 3MRGN and 4MRGN cause problems, especially in the treatment of nosocomial infections such as pneumonia and urinary tract infections .
In 2013 the Robert Koch Institute (FG14) created a sample presentation for the definition of multi-resistance in gram-negative bacteria , from the following table:
| Antibiotic group | Lead substance | enterococci bacteria |
enterococci bacteria |
Pseudomonas aeruginosa |
Pseudomonas aeruginosa |
Acinetobacter baumannii |
Acinetobacter baumannii |
|---|---|---|---|---|---|---|---|
| 3MRGN | 4MRGN | 3MRGN | 4MRGN | 3MRGN | 4MRGN | ||
| Acylureidopenicillins | Piperacillin | R. | R. | x | R. | R. | R. |
| 3rd / 4th Generational cephalosporins | Cefotaxime and / or ceftazidime | R. | R. | x | R. | R. | R. |
| Carbapenems | Imipenem and / or Meropenem | S. | R. | x | R. | S. | R. |
| Fluoroquinolones | Ciprofloxacin | R. | R. | x | R. | R. | R. |
R = resistant; S = sensitive; x (column Pseudomonas aeruginosa ) = only one of the 4 antibiotic groups effective (sensitive)
Examples and special features
As a rule, the pathogens classified in this way are non-fermenting rod-shaped bacteria (e.g. Pseudomonas aeruginosa and Acinetobacter baumannii as non-fermenters) and enterobacteria such as Escherichia coli or Klebsiella pneumoniae , some of which are in the human intestine, others in our environment can be found naturally and rarely pose problems for healthy people in everyday life. The resistance is mostly based on the production of β-lactamases . The classification is made in a microbiological laboratory using an antibiogram .
In the KRINKO recommendation on hygiene measures in the case of infections or colonization with MRGN published in the Federal Health Gazette , Table 3 shows several examples under which conditions a bacterium is classified as multi-resistant in the sense of 3MRGN or 4MRG, which happens depending on the antibiotics, to which it is resistant. Bacteria types listed there are for example:
- Acinetobacter baumannii (nonfermenter) as 3MRGN A. baumannii with resistance (R) to piperacillin, cefotaxime and ciprofloxacin, but sensitive (S) to imipenem and meropenem; as 4MRGN A. baumannii with resistance (R) to piperacillin, cefotaxime, imipenem, meropenem and ciprofloxacin, but sensitive (S) to sulbactam . Sulbactam is not included in the definition of multi-resistance.
- Pseudomonas aeruginosa (nonfermenter) as 3MRGN P. aeruginosa with resistance (R) to piperacillin, imipenem, meropenem and ciprofloxacin, but sensitive (S) to ceftazidime and cefepime ; as 4MRGN P. aeruginosa with resistance (R) to piperacillin, cefepime, imipenem and ciprofloxacin, but sensitive (S) to colistin and intermediate (I) to ceftazidime and meropenem. Intermediate results are counted as resistant results. In the case of P. aeruginosa , ceftazidime is also relevant for the assessment instead of cefotaxime (cefotaxime is not very effective against Pseudomonas ).
- Klebsiella pneumoniae (enterobacteria) as 3MRGN K. pneumoniae with ciprofloxacin (R) and ESBL; as 4MRGN K. pneumoniae with piperacillin (R), cefotaxime (R), imipenem (R), meropenem (R) and ciprofloxacin (R), but sensitive (S) to ceftazidime. According to the definition, cefotaxime and / or ceftazidime must be R or I. In the case of enterobacteria, it is recommended to count them as 3MRGN, even if one of the two cephalosporins ceftazidime or cefotaxime is tested as sensitive.
- Enterobacter cloacae (or another type of Enterobacteria with chromosomal AmpC, such as Enterobacter aergogenes (the current name is Klebsiella aergogenes ), Citrobacter freundii ) as 3MRGN E. cloacae with piperacillin (R), cefotaxime (R), ceftazidime (R) and ciprofloxacin (R), but imipenem (S) and meropenem (S). The resistance to the two cepaholsporins can be caused by overexpression of theAmpC-beta-lactamase encoded in the bacterial chromosome ; that would be an example of a natural resistance. The resistance can also be due to a plasmid-coded ESBL, an example of an acquired resistance.
Web links
- Robert Koch Institute: Antibiotic Resistance. In: Website of the Robert Koch Institute (RKI). May 21, 2015, accessed on March 29, 2018 (the date of the website only affects the start page, current articles are regularly added).
- ECDC: Antimicrobial resistance surveillance in Europe 2016. In: website European Center for Disease Prevention and Control (ECDC). November 15, 2017, accessed April 2, 2018 .
- SARI - Surveillance of antibiotic use and bacterial resistance in intensive care units. In: SARI website. Retrieved April 2, 2018 .
literature
- Recommendation of the Commission for Hospital Hygiene and Infection Prevention (KRINKO) at the Robert Koch Institute (RKI): Hygiene measures in the event of infections or colonization with multi-resistant Gram-negative rods . (PDF) In: Bundesgesundheitsblatt , Volume 55, October 2012, pp. 1311-1354, doi: 10.1007 / s00103-012-1549-5 ; ( Full text ; PDF; 1.0 MB).
- German Society for Hospital Hygiene : Action plan for multi-resistant gram-negative pathogens (MRGN) in health / care and support facilities . In: Hygiene & Medizin , 41 vol., Issue 4, 2016, mhp-Verlag, Wiesbaden, ISSN 0172-3790
Individual evidence
- ↑ a b c d Recommendation of the Commission for Hospital Hygiene and Infection Prevention (KRINKO) at the Robert Koch Institute (RKI): Hygiene measures in the event of infections or colonization with multi-resistant Gram-negative rods. In: Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz , Volume 55, 2012, pp. 1311-1354, ISSN 1437-1588 . doi: 10.1007 / s00103-012-1549-5 .
- ↑ Nils-Olaf Hübner, in coordination and using slides by Constanze Wendt (AG MRGN der KRINKO), Martin Kaase (NRZ for gram-negative pathogens): Hygiene measures in the event of infections or colonization with multi-resistant gram-negative bacterial pathogens . In: Sample presentation: Management of MRGN, Robert Koch Institute . 2013, p. 9 ( rki.de [PDF; 4.2 MB ; accessed on February 14, 2018] This presentation was created by the RKI (FG14). It may be freely reproduced and used, provided that no changes are made and reference is made to the author.).
