Research for infection protection

Hygiene management in case of multidrug-resistant Gram-negative (MRGN) pathogens

In outpatient and inpatient care facilities around the globe, multidrug-resistant Gram-negative (MRGN) bacilli develop into a serious danger. Two thirds of the deaths linked to nosocomial infection are attributed to MRGN already.

In addition to the transmission via direct contact, e.g. via ichor, sputum, urine or colonised skin, also inanimate near-patient surfaces may be a dangerous reservoir of pathogens - that is what a recent study shows.

Most common Gram-negative pathogens with multiresistance include Enterobacteria such as Escherichia coli and Klebsiella pneumoniae as well as nonfermenters such as Pseudomonas aeruginosa or Acinetobacter baumannii.

As the treatment possibilities of MRGN infections are limited considerably, avoiding infections by hygiene management is most important.

Particularly addressing hospitals, the Commission for Hospital Hygiene and Infectious Disease Prevention (KRINKO) of the Robert Koch-Institute (RKI) has updated its recommendations on how to deal with multi-resistant Gram-negative bacteria to provide a basis for effective hygiene. The recommendations’ core is the resistance pattern of individual pathogens to the most important groups of antibiotics for initial therapy of severe infections (acylureidopenicillins, 3rd and 4th generation cephalosporins, carbapenems and fluoroquinolones).

3MRGN: multi-resistant Gram-negatives being resistant to 3 of the 4 classes of antibiotics

4 MRGN: multi-resistant Gram-negatives being resistant to 4 of the 4 classes of antibiotics


Basis for the hygiene management in case of MRGN is the resistance pattern or the classification into 3MRGN and 4MRGN as well as the area-specific risks, for example, wards treating particularly immunocompromised patients. Each hospital has to define high-risk areas (e.g. neonatology, ICU, haematological oncology units).

Among the measures, a distinction is made between basic hygiene and additional measures in case of isolation.

In case of colonisation or infection with 4MRGN, measures need to exceed basic hygiene, independent of the hospital area. In case of a 3MRGN colonisation or infection, measures are usually only recommended for high-risk areas.

Overview: Prevention measures in case of 3MRGN and 4MRGN

Overview: Prevention measures in case of 3MRGN and 4MRGN
Prevention measures in case of 3MRGN and 4MRGN

Disinfectants active against MRGN

Precondition for the hygiene measures’ success is, for example, the efficacy of the disinfectants used. Several research data have repeatedly called into question the activity of QAC-based surface disinfectants without aldehyde against Gram-negative bacteria. A recent BODE SCIENCE CENTER study [1] proves the activity of different surface disinfectant cleaners against MRGN, including a product based on QAC that contains no aldehyde.

List of disinfectants active against MRGN