Confirmed cases of colonization or infection shall be reported to the local Health Unit within one business day.
Carbapenemase-producing Enterobactericeae (CPE) refers to Gram-negative bacteria belonging to the Enterobactericeae family harbouring carbapenemase-encoding genes. Carbapenemases are beta-lactamases with ability to hydrolyze penicillins, cephalosporins, and carbapenems, rendering these antibiotics ineffective. As a result, there are limited antibiotic treatment options for patients with infection due to CPE and mortality is substantially increased.
The carbapenemases that are most common in Ontario currently include; NDM, KPC, OXA-48 and VIM.
Patients with CPE colonization are asymptomatic and can only be identified by active screening; however, colonizing CPE can cause infections if they gain access to sterile body sites (e.g., lungs, bladder, bloodstream).
CPE are capable of causing difficult-to-treat infections in any part of the body, including pneumonia, bloodstream infections, intra-abdominal infections, urinary tract infections, and central venous catheter infections. Mortality in patients with CPE bacteremia may be up to 50%.
Modes of Transmission
Transmission of CPE occurs via direct or indirect contact. CPE are isolated predominantly from patients with exposures in health care facilities and can spread from person to person on the hands of healthcare workers or via shared medical equipment, particularly when hand hygiene is missed or equipment is not properly cleaned and disinfected. Transmission has also been associated with contaminated sink drains.
The incubation period for exposure-to-illness onset is undefined. Individuals colonized with CPE may remain asymptomatic if they are in good health and do not require medical interventions but can still act as a reservoir for transmission to others.
Factors that impair the function of the immune system (e.g. hematologic malignancy), and interventions which permit colonizing bacteria to invade (e.g. indwelling devices) increase the probability of infection with CPE.
Period of Communicability
The period of communicability of CPE persists as long as the organism is present in the gastrointestinal tract of the patient. Several studies have evaluated duration of colonization of patient populations in different countries with varying results. Patients can be intermittently positive on repeat screening and may be colonized for months to years.
The primary risk factor for acquiring CPE is exposure to patients in health care facilities with prevalent CPE. Patients who have received health care outside of the country or who are known contacts of CPE should be screened. People coming from the Indian subcontinent with or without exposure to health care, are also at risk.
Diagnosis and Laboratory Testing
CPE are identified by any Ontario microbiology laboratory. A case of CPE is any patient with a positive isolate of CPE, regardless of the presence of signs and symptoms of clinical findings.
See Labstract below.
Treatment and Case Management
Because CPE are resistant to all penicillins, cephalosporins, and carbapenems, treatment of infections is difficult and involves the use of antibiotics with poor adverse event profiles and/or reduced efficacy (e.g., colistin, tigecycline). The isolation of CPE should be considered to be a critical laboratory result.
For case management recommendations, refer to the Provincial Infectious Diseases Advisory Committee, Annex A document “Screening, Testing and Surveillance for Antibiotic-Resistant Organisms (AROs)”. Current expert recommendations are that patients remain on contact precautions for the duration of hospitalization. Pay particular attention to sink cleaning and disinfection.