Patients who had M. chimaera bacterial infections within 6 years of open-heart surgery are filing lawsuits against the manufacturer of the Stockert 3T Heater-Cooler, a hospital machine that was contaminated with M. chimaera in Germany.
What is M. Chimaera?
Mycobacterium chimaera (M. chimaera) belongs to a group of bacteria known as Non-Tuberculosis Mycobacteria (NTM). They are very commonly found in water and soil in the environment. Healthy people are not normally at risk of infections with NTM bacteria, but it can be a problem for surgery patients or people who are very sick.
What is Mycobacterium Avium Complex?
Mycobacterium Avium Complex (MAC) is the medical name for a serious infection with M. chimaera and other NTM bacteria. Most cases of MAC are lung infections (pneumonia) in people with cystic fibrosis and other underlying illnesses, but MAC can also occur in healthy people. M. chimaera was only recently identified as a potential cause of MAC because it was not discovered until 2004.
Heater-Cooler Infections With M. Chimaera
Heater-cooler units are machines that are used in the operating room of hospitals that perform open-heart surgery. Heater-coolers use water to regulate the body temperature of patients undergoing surgery.
The problem is that M. chimaera can grow in the water tanks of a heater-cooler unit and spray out of the exhaust vents on the back of the machine into the air. If M. chimaera lands on a patient undergoing surgery, the patient may develop an infection months later.
What Causes M. Chimaera Infections?
Stockert 3T Heater-Cooler Units have been linked to outbreaks of infections with M. chimaera. Less than 1% of people who undergo open-heart surgery will develop this type of infection — but up to 50% of M. chimaera infections cause death. The Stockert 3T was first linked to infections at hospitals in Switzerland in 2012.
Stockert 3T Heater-Coolers Contaminated in Germany
In 2016, the FDA published a Safety Communication to warn that evidence “strongly suggests” that Stockert 3T Heater-Cooler Units were contaminated with M. chimaera from the same source — and it was almost certainly the water used at a manufacturing facility in Germany. That means most Stockert 3T Heater-Coolers that were shipped to the U.S. since 2006 may be contaminated with bacteria.
Symptoms of M. Chimaera Infections
The symptoms of M. chimaera infections may not appear for up to 6 years following open-heart surgery. The symptoms may include:
- Shortness of breath
- Unexplained weight-loss
- Persistent cough (or coughing up blood)
- Night sweats
- Muscle pain
- Abdominal pain
- Redness,heat, or pus at the surgical site
- Joint pain
Treatment for M. Chimaera Infections
M. chimaera is a slow-growing bacteria that can survive most normal types of antibiotics. Treatment for this infection involves a cocktail of several powerful antibiotics for 18 months — up to a few years. Deafness and blindness are potential side effects of long-term treatment with antibiotics. Patients who were infected during a heart valve implant or replacement will also likely need additional surgery. Without treatment, M. chimaera infections can cause death.
How Many Heater Coolers Are Contaminated?
Experts warn that nearly all people who had open-heart surgery in the U.S. since 2006 were exposed to a risk of M. chimaera infections from the Stockert 3T Heater-Cooler and similar machines.
In March 2017, a study discovered M. chimaera in 14 out of 16 of the Stockert 3T Heater-Cooler Units that came from 5 hospitals in Denmark. The researchers warned:
“We find it likely that most Sorin 3T Heater-Cooler Units made in the past 8-10 years potentially are contaminated by the same M. chimaera strain. In addition, because 80% of the Maquet Heater-Cooler Units also contained M. chimaera … we suggest mycobacterial contamination might be a general problem for Heater-Cooler Units.”