Information about carbapenem-resistant organisms (CRO)
CRO belong to a family of Gram-negative bacteria (sometimes known as coliforms). They include Enterobacteriaceae (such as E. coli, Klebsiella spp. and Proteus spp.) and are part of the normal range of bacteria found in the gut.
When the bacteria live harmlessly in the gut this is called ʻcolonisationʼ. However, CRO are some of the most common causes of many infections, including urinary tract infections, bloodstream infections and intra-abdominal infections, all of which can be life-threatening.
CRO are extremely resistant to antibiotics. These bacteria have become resistant through producing enzymes that break down carbapenem antibiotics.
Why does carbapenem-resistance matter?
Carbapenem antibiotics are a powerful group of penicillin-like antibiotics that are used in hospitals. Until recently, they have been the group of antibiotics that clinical teams could rely on (if other antibiotics failed) to treat serious infections caused by Gram-negative bacteria. The rapid spread of carbapenem-resistant bacteria poses an increasing threat and risk to public health.
Due to the lack of new antibiotics being developed, carbapenems may be considered as a last resort and a critically important antibiotic resource that must be preserved.
How common are CRO?
Over the last decade CRO have spread throughout the world, partly due to overuse of antibiotics, poor hygiene and sanitation, and international travel. Until recently, most cases identified in the UK were associated with people who had been in hospital abroad. However, the number of CRO cases is increasing and there are already areas in the UK where CRO are considered endemic (regularly found). There is a growing risk that CRO could become endemic across UK healthcare.
How are CRO spread?
CRO are most commonly spread through direct contact with the patient or indirectly from the patient's care environment (including care equipment). Consistently applying Standard Infection Control Precautions and Transmission-based Precautions, specifically contact Transmission-based Precautions, is required to prevent the spread of CRO.
How do we know which patients to screen?
All patients should have a clinical risk assessment for CRO when they are admitted to hospital. This will identify high-risk patients that need to be screened. The following patients are considered to be at high risk of CRO.
- –Patients who have been transferred from a hospital or healthcare facilities abroad in the past 12 months (including patients who were admitted for dialysis while on holiday abroad).
- –Patients who in the past 12 months have been an inpatient in a UK hospital where CRO are considered endemic (including patients who were admitted for dialysis).
- –Patients who have previously been infected or colonised with a CRO in the past 12 months.
Patients identified as high risk by the clinical risk assessment should be screened and isolated in a single room until the results of the test are known.
Managing patients with confirmed or suspected CRO
How should patients colonised or infected with a CRO be managed?
- –You should apply Standard Infection Control Precautions and contact Transmission-based Precautions.
- –Patients colonised or infected with CRO should be isolated in a single room, preferably en-suite, and screened every week during their stay (unless the clinical care team says otherwise).
- –Surfaces that are often used or touched should be cleaned at least twice a day.
- –The infection control team will advise on any further necessary precautions.
- –Patients who are colonised do not need to be treated unless advised by the clinical care team. If an infection is confirmed, the clinical team and the infection control doctor must discuss the most appropriate antimicrobial treatment.
- –If the patient needs to be transferred to another ward, unit or hospital, you must tell that ward, unit or hospital the patient's CRO status.
- –You should provide information leaflets for the patient and their relatives and discuss the leaflets with them.
- –Advise relatives and visitors to wash their hands with soap and water before entering and leaving the patient's room. They do not have to wear personal protective equipment.
- –If the patient is readmitted from a community setting, you must apply standard infection control precaution and transmission-based precautions.
In the community
- –You must follow Standard Infection Control Precautions.
- –You do not need to make patients with CRO your last scheduled home visit, as Standard Infection Control Precautions are enough to prevent CRO spreading.
- –Patients in the community do not need to be screened weekly for CRO.
- –Crockery, cutlery and so on can be washed as normal.
- –Clothes and bed linen can be washed as normal at the hottest temperature suitable for the fabric. If laundry is soiled it should be washed separately, preferably at 60°C.
- –There is no restriction on visitors, but they should be encouraged to wash their hands with soap and water when entering and leaving the patient's room.
Can I still care for a patient who has a CRO if I am pregnant?
- –There is no extra risk to healthcare workers who are pregnant, but if you have any concerns contact your local Occupational Health Department or Infection Control Team.
I have cared for a patient with a suspected or confirmed CRO. Should I be tested?
- –There is no need for you to be tested for CRO, unless your Infection Control Team or Occupational Health Team requests it.
You can get further advice from your local Infection Prevention and Control Team or Health Protection Team.
This leaflet has been produced by a working party led by Health Protection Scotland on behalf of the joint societies – British Infection Association (BIA), British Society for Antimicrobial Chemotherapy (BSAC), Infection Prevention Society (IPS) and Healthcare Infection Society (HIS).