Melbourne researchers have used cutting-edge genomics technology to prove that a strain of bacteria can be transmitted to patients from machines that are generally employed in the regulation of body temperature during cardiac surgery. Mycobacterium chimaera is a pathogen previously associated with LivaNova Stöckert 3T cooling and heating units in the hospitals across the Northern Hemisphere.
The infection could be responsible for serious illness, and three cases have already been reported in Australia, two of which were in New South Wales, while the third one was identified in Queensland.
Possible Infections With Mycobacterium Chimaera
As part of a collaboration between sites across New Zealand and Australia, scientists from the Peter Doherty Institute for Infection and Immunity have proven that the units were the ones responsible for the bacterial transmission that infected the patients, according to the press release.
After having analyzed 48 samples of Mycobacterium chimaera collected between May 2015 and July 2016, the researchers published their results in the New England Journal of Medicine. The samples employed in the analysis were collected from cooling and heating units, and five of them were retrieved from patients.
"To test this hypothesis, we compared the M. chimaera genome data from our patient with recently released sequences from tests of heating and cooling units in the Northern Hemisphere. We found a high level of DNA sequence conservation; this finding was again consistent with pathogen spread from a point source," noted the research.
The deputy director of the institute, Dr. Deborah Williamson, declared that the researchers believe the units had been pre-contaminated during the manufacturing process. Additionally, the pathogen is "very hardy," according to the director's statement, and symptoms may be delayed because of the latent infection it causes once installed in the human body.
The researchers will employ whole-genome sequencing technology in the process of creating a fast diagnostic test that could be reliable for possible patients. This immediate preoccupation of the researchers will be helped by data sharing of national and international institutions in this field of activity.
"Our observations highlight the potential for global dissemination of contaminated medical devices, including to regions such as Australia and New Zealand. These data show the value of combining high-resolution molecular analysis and public sharing of sequence data to improve responses to outbreaks that have potential public health importance," concluded the paper.
Patients Who Went Through Open Heart Surgery, Possibly In Danger
At the same time, CDC warns health care providers, as well as patients, concerning the potential risk of infection due to some devices employed in open heart surgeries.
Patients who have gone through an open heart surgery and experience symptoms of infection, such as muscle aches, night sweats, fatigue, weight loss, or unexplained fever, are advised to seek medical care.
Every year, more than 250,000 bypass procedures are performed across the United States, each of which uses heater-cooler devices. The units are highly important in these surgeries, as they allow the patients' blood to circulate, and they keep their organs at a very specific temperature during the operation.
"Approximately 60 percent of heart bypass procedures performed in the U.S. utilize the devices that have been associated with these infections. CDC estimates that in hospitals where at least one infection has been identified, the risk of a patient getting an infection from the bacteria was between about 1 in 100 and 1 in 1,000," notes the CDC website.
