M. CHIMAERA INFECTION
ASSOCIATED WITH
WATER-BASED
HEATER-COOLER UNITS
WATER-BASED
HEATER-COOLER UNITS WHAT IS HAPPENING?
- Water-based heater-cooler units have been identified as a source of nontuberculous mycobacteria (NTM) infections in heart surgery1-2
- Heater-cooler unit contamination with M. chimaera was first described in Europe in 2014 after 6 infected patients led to an investigation of the outbreak. Later investigations confirmed this association2
- The contaminated water can be aerosolised, transmitting bacteria via bioaerosols through the air and through the device’s exhaust vent into the environment and into the patient3
NONTUBERCULOUS MYCOBACTERIA (NTM)
CHARACTERISTICS
- Nontuberculous mycobacteria (NTM) are a heterogeneous group of bacteria composed of 169 different species categorised in the family of mycobacteria4
- Nontuberculous mycobacteria (NTM) are commonly found in water sources4,5
- Nontuberculous mycobacteria (NTM) can survive for weeks to months on biologically inert surfaces6,7
- M. chimaera are a slow growing Nontuberculous mycobacteria (NTM) that form biofilms that are resistant to many disinfectants6,7
≥1000 times more resistant to disinfectants than Escherichia coli, the industry standard for disinfection
THE ROLE OF HEATER-COOLER IN<br>THE EXTRACORPOREAL CIRCUIT
The heater-cooler units are functional and integral components of the extracorporeal circuit in surgeries requiring cardiopulmonary bypass. The main function of a heater-cooler unit is to regulate the temperature of the patient.8
A temperature-regulated fluid circulates along one side of a heat exchanger surface, whilst blood or a cardioplegia solution circulates on the opposite side to achieve the cooling. The heater-cooler units are subsequently used to warm the patient’s blood after the surgery.8
M. CHIMAERA INFECTION
SOME DATA
Annual Incidence
In over 300,000 global annual valve replacement surgeries in the 10 major market countries, an estimated annual incidence of 156–282 cases was calculated.9
Clinical Manifestations
Fever is the most common symptom for M. chimaera infection and is present in 80% of cases.10
Other patient symptoms include: weight loss, shortness of breath, night sweats and fatigue.10
Patients at Risk
Current evidence suggests patients undergoing cardiac valve surgery are at particular risk.11-12-13
Treatment
Treatment regimens recommended for M. chimaera infection rely on combination of multiple antimicrobial drugs.14,18
When a disseminated M. chimaera infection is diagnosed, foreign material removal or exchange is also recommended.14
Common Treatment Failure
The high mortality rate is probably multifactorial, resulting from late diagnosis and treatment, intrinsic drug resistance of M. chimaera.12
M. CHIMAERA INFECTION
economics of treatment
The most common clinical manifestations observed as a consequence of M. chimaera are16
- Prosthetic Valve Endocarditis (PVE)
- Infective Endocarditis (IE)
In two German studies15-18, the costs associated with surgery and hospitalisation for patients with prosthetic valve endocarditis (PVE) were examined. The mean total hospital costs per patient ranged from €42,600 (± €37,400) to €72,096 (± €53,524) per patient15-18.
Treatment of prosthetic valve endocarditis (PVE) in Germany exceeded €100,000 per patient in 10% of cases15.
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Acosta F, Perez-Lago L, Ruiz Serrano M, et al. Fast update of undetected Mycobacterium Chimaera infections to reveal unsuspected cases. J Hosp Infect. 2018;100:451-455. doi:10.1016/j.jhin.2018.08.018
Sax H, Bloemberg G, Hasse B, et al. Prolonged Outbreak of Mycobacterium Chimaera Infection After Open-Chest Heart Surgery. Clin Infect Dis. 2015;61:67-75. doi:10.1093/cid/civ198
Schreiber PW, Sax H. Mycobacterium Chimaera infections associated with heater – cooler units in cardiac surgery. Curr Opin Infect Dis. 2017;30(4):388-394.doi:10.1097/QCO.0000000000000385
Sousa S, Bandeira M, Carvalho PA, Duarte A, Jordao L. Nontuberculous mycobacteria pathogenesis and biofilm assembly. Int J Mycobacteriology. 2015;4(1):36-43.doi:10.1016/j.ijmyco.2014.11.0655. 2
Allen KB, Yuh DD, Schwartz SB, et al. Nontuberculous Mycobacterium Infections Associated With Heater-Cooler Devices. Ann Thorac Surg. 2017;104(4):1237-1242.doi:10.1016/j.athoracsur.2017.04.067
Schulze-Röbbecke R, Buchholtz K. Heat susceptibility of aquatic mycobacteria. Appl Environ Microbiol. 1992;58(6):1869-1873.http://www.ncbi.nlm.nih.gov/pubmed/1622262. Accessed May 10, 2019.
Falkinham J. Common Features of Opportunistic Premise Plumbing Pathogens. Int J Environ Res Public Health. 2015;12(5):4533-4545. doi:10.3390/ijerph120504533
https://www.fda.gov/medical-devices/cardiovascular-devices/what-heater-cooler-device
Rami Sommerstein, Barbara Hasse, Jonas Marschall, Hugo Sax, Michele Genoni, Matthias Schlegel, Andreas F. Widmer, and the Swiss Chimaera Taskforce. Global Health Estimate of Invasive Mycobacterium Chimaera Infections Associated with Heater – Cooler Devices in Cardiac Surgery. Emerg Infect Dis. 2018;24(3):1-3
Scriven JE, Scobie A, Verlander NQ, et al. Mycobacterium Chimaera infection following cardiac surgery in the United Kingdom: clinical features and outcome of the first30 cases. Clin Microbiol Infect. 2018;24(11):1164-1170. doi:10.1016/j.cmi.2018.04.02
Kanamori H, Weber DJ, Rutala WA. Healthcare-Associated Mycobacterium Chimaera Transmission and Infection Prevention Challenges : Role of Heater-Cooler Unitsas a Water Source in Cardiac Surgery. Clin Infect Dis. 2017;27514(3):343-346. doi:10.1093/cid/ciw755
Walker J, Moore G, Collins S, et al. Microbiological problems and biofilms associated with Mycobacterium Chimaera in heater - cooler units used for cardiopulmonary bypass. J Hosp Infect. 2017;96(3):209-220. doi:10.1016/j.jhin.2017.04.014
Chand M, Lamagni T, Kranzer K, et al. Insidious Risk of Severe Mycobacterium Chimaera Infection in Cardiac Surgery Patients. Clin Infect. 2017;64(3):335-342.doi:10.1093/cid/ciw754
Kasperbauer SH, Daley CL. Mycobacterium Chimaera Infections Related to the Heater-Cooler Unit Outbreak: A Guide to Diagnosis and Management. Clin Infect Dis.2018;68(7):1244-1250. doi:10.1093/cid/ciy789
Grubitzsch H, Christ T, Melzer C, Kastrup M, Treskatsch S, Konertz W. Surgery for prosthetic valve endocarditis: Associations between morbidity, mortality and costs. Interact Cardiovasc Thorac Surg. 2016;22(6):784-791. doi:10.1093/icvts/ivw035
Sommerstein, Rami; Rüegg, Christian; Kohler, Philipp; Bloemberg, Guido; Kuster, Stefan P; Sax, Hugo (2016). Transmission of mycobacterium chimaera from heater-cooler units during cardiac surgery despite an ultraclean air ventilation system. Emerging Infectious Diseases, 22(6):1008-1013.
Kuehn C, Graf K, Heuer W, et al. Economic implications of infections of implantable cardiac devices in a single institution. Eur J Cardio-thoracic Surg.2010;37(4):875-879. doi:10.1016/j.ejcts.2009.10.01817
Hasse B, Hannan MM, Keller PM, et al. International Society of Cardiovascular Infectious Diseases Guidelines for the Diagnosis, Treatment and Prevention of Disseminated Mycobacterium chimaera Infection Following Cardiac Surgery with Cardiopulmonary Bypass. J Hosp Infect. 2020;104(2):214-235. doi:10.1016/j.jhin.2019.10.00
Acosta F, Perez-Lago L, Ruiz Serrano M, et al. Fast update of undetected Mycobacterium Chimaera infections to reveal unsuspected cases. J Hosp Infect. 2018;100:451-455. doi:10.1016/j.jhin.2018.08.018
Disseminated Mycobacterium chimaera Following Open-Heart Surgery, the Heater-Cooler Unit Worldwide Outbreak: Case Report and Minireview Emmanuel Lecorche 1 2 3, Gauthier Pean de Ponfilly 3, Faiza Mougari 1 2 3, Hanaa Benmansour 1 2 3, Elodie Poisnel 4, Frederic Janvier 5 6, Emmanuelle Cambau 1 2 3