Carbapenemase-Producing Enterobacteriaceae

What are CPE?

Carbapenemase-producing Enterobacteriaceae (CPE) [also known as carbapenem-resistant Enterobacteriaceae (CRE)] is the collective name for a family of microorganisms that have high levels of resistance to antibiotics. Two of the most common bacteria in the Enterobacteriaceae family that can develop resistance to carbapenem antibiotics family include Escherichia coli (E. coli), and species of Klebsiella. Others include species of Serratia, Enterobacter, Salmonella and Citrobacter.

CPE are sometimes referred to by the names of the enzymes – the carbapenemases – that break down carbapenem antibiotics such as imipenem, ertapenem, meropenem and doripenem. Three well-known CPE include KPC (Klebsiella pneumoniae carbapenemase), NDM (New Delhi Metallo-beta-lactamase) and OXA-48. CPE are resistant to many antibiotics, with some being resistant to all or almost all antibiotics. As a result, infections are very difficult to treat; CPE bloodstream infections can kill 1 in 2 patients.

Globally, there are many different carbapenemase-encoding genes and many different resultant carbapenemases. The carbapenemases that are most common in Ontario currently included NDM, KPC, OXA-48 and VIM. 1

Why are CPE a concern?

CPE are a concern globally for a number of reasons.2

  • Some CPE are resistant to multiple classes of antibiotics, not just carbapenemases.
  • With some carbapenemases such as KPC, the genes that code for resistance are on a highly mobile genetic element which can be transmitted from one Enterobacteriaceae to another, facilitating the transmission of resistance from one species to another.
  • Mortality rates from some CPE infections are as high as 50%.
  • CPE cause infections in both community and healthcare settings.

Who is at risk of CPE infections?

CPE infections most commonly affect already sick patients in acute and long-term healthcare settings who are typically being treated for other conditions. Risk factors also include having a compromised immune system, having invasive devices such as catheters or mechanical ventilators going into the body, or use of certain types of antibiotics (such as carbapenems, cephalosporins, fluoroquinolones, and vancomycin).3 Several outbreaks of CPE have also been reported amongst patients undergoing a life-saving medical procedure called ERCP (endoscopic retrograde cholangiopancreatography) in which a duodenoscope is inserted through the mouth and intestine to where the bile duct attaches.4 Some CPE have originated in overseas countries such as India (NDM) so receipt of healthcare in countries where CPE is endemic may also be a risk factor.

Patients may also be colonized with CPE, meaning that the organism can found in a clinical culture but not be causing an infection. In such cases, infections may result if the colonized strain access sterile body sites such as the bloodstream, lungs and bladder. Signs and symptoms may then include those commonly associated with those body sites but also general fever and chills.

How are CPE spread?

CPE spread primarily in healthcare settings and often through person to person transmission from the contaminated hands of healthcare personnel or contaminated equipment to patients. Transmission from the environment directly to patients is not well-understood and requires more research. However, studies are showing that CPE can exist on surfaces and equipment in the environment and could contaminate healthcare personnel hands and then be transmitted to patients. One study has found CPE on a variety of surfaces in the rooms of patients infected with KPC, with the bed linen and area around the bed being the most contaminated.5 In recent years, multiple studies have shown that hospital sink drains and particularly those in the ICU can be reservoirs.6 Water from faucets hitting the contaminated sink drain can splash to surrounding surfaces containing IV bags, medications and patient equipment. Some studies have also demonstrated that contaminated sinks were the source of CPE outbreaks.7,8

Preventing the Spread of CPE

PIDAC provides useful guidance and resources for controlling and preventing the spread of CPE in healthcare facilities.9

1. Routine Practices: Consistent use of Routine Practices with all patients/residents.

2. Screening: Surveillance is an important measure to prevent and control the spread of CPE. Admission screening and pre-emptive Contact Precautions are indicated for individuals with risk factors for CPE:

  • If a patient/resident is identified with CPE, roommates and patients in close proximity will be screened for CPE
  • Primary screening specimens for CPE are stool or rectal swabs. Urine specimens and swabs from open wounds may also be indicated. In critical care settings, sputum or endotracheal tube specimens and swabs from exit sites may be requested by Infection Prevention and Control
  • Patients with known CPE carriage will have their records flagged, will be placed on Contact Precautions and will be re-screened if readmitted.

3. Initiate Contact Precautions for patients/residents with CPE:

  • Appropriate client/patient/resident placement
  • Gloves for all activities in the patient’s room or bed space in acute care, or for direct care of
    clients/residents in long- term care and ambulatory/clinic settings
  • Long-sleeved gown for activities where skin or clothing will come in contact with the patient or their environment in acute care, or for direct care of clients/residents in long- term care and ambulatory/clinic settings
  • Dedicated equipment or adequate cleaning and
    disinfecting of shared equipment, with particular attention to management of urinary catheters and associated equipment

4. Inform: Notify the Infection Prevention & Control Professional or delegate to discuss the infection control management of client/patient/resident activities.

5. Colonization: It is not known how long bowel colonization with CPE persists, but it is likely of long duration. Most colonized patients/residents are asymptomatic. Because of the implications of CPE infection and transmission, current expert recommendations are that patients remain on Contact Precautions for the duration of hospitalization. They should be presumed to be colonized and managed on Contact Precautions if they are readmitted.

6. Decolonization: There are no data to support CPE decolonization and it is not recommended.

Clorox Healthcare® products with Health Canada-approved claims against CPE

A number of Clorox Healthcare® disinfectants have Health Canada-approved claims against some common CPE.

Product            DIN No     Klebsiella
pneumoniae
(KPC)		 Klebsiella
pneumoniae
(NDM-1)		 Escherichia
coli (carbapenem-
resistant)		 Escherichia coli
(NDM-1)		 Enterobacter cloacae
(NDM-1)
Clorox Healthcare® Bleach Germicidal Wipes 02465671 30 sec 30 sec 30 sec
Clorox Healthcare® Bleach Germicidal Cleaner 02469278 1 min 1 min 1 min 1 min
Clorox Healthcare® Fuzion® Disinfectant Cleaner 02459744 1 min 1 min
Clorox Healthcare® Hydrogen Peroxide Cleaner Disinfectant 02403528 30 sec 30 sec
Clorox Healthcare® Hydrogen Peroxide Cleaner Disinfectant Wipes 02403528 30 sec 30 sec
Clorox Healthcare® VersaSureTM Cleaner Disinfectant Wipes 02473151 2 min 2 min
Clorox Healthcare® Spore DefenseTM Cleaner Disinfectant 02494663 1 min
Clorox® Total 360® Disinfecting Cleaner 02460769 2 min 2 min

References

1. Ontario Ministry of Health and Long-Term Care. Infectious Disease Protocol. Appendix A: Disease-Specific Chapters. Carbepenemase-producing Enterobacteriaceae (CPE) infection and colonization. http://www.health.gov.on.ca/en/pro/programs/publichealth/oph_standards/docs/CPE_chapter.pdf
2. Centers for Disease Control and Prevention. Carbapenem-resistant Enterobacteriaceae (CRE) Infection: Clinician FAQs. https://www.cdc.gov/hai/organisms/cre/cre-clinicianfaq.html
3. Bhargava A et al. Risk Factors for Colonization due to Carbapenem-Resistant Enterobacteriaceae among Patients Exposed to Long-Term Acute Care and Acute Care Facilities. Infection Control and Hospital Epidemiology, 2014; 35(4): 398-405.
4. CDC Statement: Los Angeles County/UCLA investigation of CRE transmission and duodenoscopes. July 10, 2015. https://www.cdc.gov/hai/outbreaks/cdcstatement-la-cre.html
5. Lerner A et al. Environmental Contamination by Carbapenem-Resistant Enterobacteriaceae. J Clin Microbiol. 2013; 51(1): 177–181.
6. Kizny A et al. The Hospital Water Environment as a Reservoir for Carbapenem-Resistant Organisms Causing Hospital-Acquired Infections—A Systematic Review of the Literature. Clinical Infectious Diseases. 2018; 64:1435-1444.
7. De Geyter A et al. The sink as a potential source of transmission of carbapenemase-producing Enterobacteriaceae in the intensive care unit. Antimicrobial Resistance and Infection Control, 2017; 6:24-29.
8. Regev-Yochay G et al. Sink traps as the source of transmission of OXA-48–producing Serratia marcescens in an intensive care unit. Infection Control & Hospital Epidemiology 2018; 39:1307–1315.
9. PIDAC, Carbapenemase-producing Enterobacteriaceae (CPE) Sample fact sheet for health care staff. https://www.publichealthontario.ca/-/media/documents/r/2013/rpap-cpe-sample.pdf?la=en. Accessed on August 21, 2020