Questions & Answers from the 2013 NTM Patient/Physician Conference

Does having NTM make one more susceptible to arthritis or osteoporosis?

NTM does not predispose you to arthritis or osteoporosis. However, having arthritis and being treated with certain types of medications, such as TNF inhibitors or other immunosuppressant drugs, can make you more susceptible to getting an NTM infection.

How much do conditions such as Bronchiectasis or COPD increase the chance of getting an NTM infection?

Bronchiectasis is in fact a form of COPD, and COPD generally makes one more susceptible to NTM infection. In the case of Bronchiectasis, we know it is one of the most significant risk factors for pulmonary NTM infection susceptibility.

If a patient has had multiple NTM infections including one which is resistant to rifampin, and is currently on Ethambutol, rifabutin and azithromycin, is it safe to continue taking the ethambutol, or will it make the infection more resistant? How are patients with resistant strains treated? Is there anything patients can do to prevent future infections?

Many patients with resistant strains are treated on a regular and ongoing basis, which helps keep the infection at bay and helps prevent significant further damage to lung tissue. It is usually considered helpful to have your NTM culture tested for sensitivity to drugs, as this will help your doctor decide which course of treatment would be most effective.

As for preventing future infections, there are many steps one can take to reduce exposure and therefore help mitigate the chances of getting another infection.

Will using boiled sterilized water for drinking and cooking help reduce the chances of NTM reinfection?

Generally, this would tend to be useful if a patient also suffers from gastroesophageal reflux disease (GERD), as aspiration into the lungs from reflux may be a source of NTM exposure in the lungs.

What is a reasonable length of time to boil water to eradicate the NTMs in it?

Ten minutes at a rolling boil is sufficient to kill the mycobacteria in the water.

Do I need to avoid steam from such things as boiling water on the stove for coffee or steaming vegetables? What about humidity? Should I not use a swamp cooler and use air conditioning instead? Should I avoid anything that humidifies the air?

Steam from boiling water will likely lack any viable NTM as they are killed by boiling.

We’ve found that NTM are readily aerosolized from the water we put in humidifiers. High numbers of either Mycobacterium avium or Mycobacterium abscessus could be recovered from the air in a bathroom-sized room after 10 minutes of operation of an “ultrasonic” humidifier. Note that there are several types of humidifiers, including ultrasonic, paddle and evaporative, and they may be different in their aerosolization.

Ultrasonic humidifiers generate a real fog with lots of very small droplets containing NTM that are of a size able to enter the furthest reaches of the lung: the alveoli. Paddle humidifiers likely generate larger droplets of water that may not enter the lung very well, but there are no data on the amounts of NTM present. Evaporative humidifiers heat water and generate mist. The amount of mycobacteria in their droplets remains to be measured.

Separate from the type of humidifier is the fact that the water placed in it may have NTM. If the humidifier is refilled on a regular basis without any cleaning (detergent scrub the walls) or disinfection (undiluted household bleach for 30 minutes), NTM numbers will rise as they grow on the wall of the reservoir. If you do need a humidifier, clean and rinse carefully to get rid of the bleach, and fill it with boiled water. Ten minutes at a rolling boil will kill the NTM in your household water.

Do you advise people who have had repeated NTM infections NOT to garden (because of the NTM in the soil)?

Not necessarily. Experts suggest wetting the potting soil to prevent dust formation, and wearing a “dust” mask.

What is the best mask to use to prevent exposure from mycobacteria if wanting to do yard work or even if going on the airplane to prevent being exposed to other germs?

No one has yet performed a systematic survey, but in addition to wetting the potting soil to prevent dust and particles, it is a good idea to wear a surgical or "dust" mask.

Is it OK to run additional hot water into a bathtub after you are already in the tub?

As long as you don’t generate aerosols while filling the bath with lots of splashing at high water velocities, and as long as there isn’t a great deal of splash in general, a bath should not generate NTM aerosols.

Does swimming in an outdoor pool further expose me to mycobacteria, and if so is the exercise benefit to my lungs more beneficial than the risk of exposure? What about an indoor pool?

Swimming pools can have NTM as the concentration of chlorine will not kill NTM, but the size of the water droplets generated by splashing tend to be too large for aerosolization. To avoid any NTM aerosols (mist) swim in an outdoor pool, and be mindful of not swallowing or inhaling water.

At what rate do mycobacteria grow in our household plumbing?

Great question, and one without a definitive answer at this time. However, we do know that NTM numbers double between the treatment plant and household and that water can be 1-2 days old. That means they grow in the distribution system at approximately one generation per day; the same rate as they grow in natural water samples in the laboratory. A distribution systems (pipes and biofilms) is not too different from household plumbing. However, in households NTM may grow faster because they get warmed in hot water pipes.

If we make the water hotter to eliminate the NTMs, are they constantly being replaced with new growth?

As really hot water (such as greater than 130° F) will kill NTM they will not be able to reproduce and form new cells.  There are two caveats: (a) Killing is not 100 %, some cells survive; 99.9 % of M. avium cells are killed in 4 min at 130° C meaning 0.1 % of the initial population survive. (b) As we use water in the house, it is replaced by water from the distribution system that can re-seed the household.

If increased water temperature leads to more steam, is this more dangerous when bathing and showering?

Because the higher temperature kills NTM in the water, the steam has fewer NTM that are alive.

What water temperature is preferred especially when showering or bathing?

We can separate high hot water heater temperatures to kill NTM from bathing and shower temperatures.  They are really independent and there is no need to shower in very hot water.  Shower or bath temperature is really a personal preference and adjusted by balancing hot and cold. Thus, if you prefer to shower with cool water (e.g., in the south during the summer), you can have high hot water temperatures (greater than 130° C), yet still mix in loads of cold to shower or bathe comfortably.

What do we know about tankless water heaters and NTM growth?

We don’t know nearly enough, but that is on the NTM research agenda. In some parts of the country, such water-saving measures are now being mandated by regulation. A study done at Virginia Tech showed that there are really no savings of energy.

I’ve learned that water should be filtered to .2 microns or below. What types of filtration systems can accomplish this for drinking and showering?

The 0.22 micrometer (micron) pore size is to prevent the transmission of NTM and other bacteria. Granular activated carbon (charcoal) filters have significantly larger pores so don’t prevent the passage of NTM and other bacteria. There are a few manufacturers producing inline or point of use filters (e.g., Pall Medical, that have 0.22 micrometer pore size filters.

Is it beneficial to boil our drinking and/or cooking water? ALSO: I use only bottled water and boil all water for cooking and drinking for 10 minutes prior to use. I also use a UV light for water when traveling. Are these steps recommended?

First, it is not been proven that bottled water is necessarily free of NTM and other bacteria. Bottled water is difficult to assess for presence of NTM and bacteria as there are a very large number of suppliers and sources. Further, bottled water faces fewer regulatory regulations compared to pipe-delivered drinking water. That having been mentioned as a caveat, boiling and UV irradiation can be effective in reducing numbers of NTM and other microorganisms and viruses. Water must be boiled 10 min to kill NTM, other bacteria, and viruses. Depending upon the strength of the UV-source, the length of time to kill NTM, bacteria, and viruses may vary.

Can MAC attack the digestive tract by the water we drink or by food we eat? If so, how is it tested for and treated?

Generally, NTMs are destroyed in the stomach by the digestive acids present. If a patient takes a proton pump inhibitor (PPI) for gastroesophageal reflux disease (GERD), those acids are reduced and NTMs may remain there. The concern is over reflux and aspiration of it into the lungs, where it is a source of NTM exposure.

What is the best way to wash hair in order to limit exposure?

Though there hasn’t been much discussion of this issue prior to your question, one way would be to avoid generating a fine mist that could be inhaled. Wash with a nice fat stream of water.

Specifically regarding MAC, can it be eliminated, or will it return from time to time?

This would depend on both the patient and the strain causing the infection. If the strain is resistant to antibiotics, it is more likely that the infection will remain, though it could be kept at relatively stable levels through ongoing treatment. However, risk of an exacerbation would always remain. Some NTM infections – again, depending on the strain – can be eliminated, but if there is any underlying co-morbidity that would predispose you to infection, then there would be an ongoing risk of getting infected with NTM again, either the same strain or a different one.

Frequent analysis of a sputum sample is the mainstay of our non-invasive ability to monitor NTM. Yet there is much variation in specimen delivery methods that can affect the results. Additionally there are variations in testing procedures, equipment and/or standardization among laboratories that often makes follow-through on the process a frustrating if not misleading endeavor. Are there answers to this on the horizon? Are any new non-invasive monitoring methods being researched?

Multiple sputum tests, taken over a period of time, are a valuable monitoring tool because they give you the pattern or trend in your infection.

What are the statistics on surgery to remove the middle right lobe? Would this cure or lessen the symptoms? How long is the recovery period?

Not a lot of data are available on this, but the information we do have suggests a low rate of complication and a high conversion rate to negative cultures. Of course there are differences between patients that also have an impact: how complicated is the surgery? Generally the more complex the surgery the more risk there is of complications arising, and this is true of thoracic surgery in general.

Has anyone ever been cured of NTM, or of its symptoms such as persistent cough? How would you define “cured”?

Different papers state different “cure” rates, but the problem is how you define “cure.” Does that mean culture negative for 1, 3, 5 or 10 years? In the experience of many doctors, over 50% of patients relapse when followed over a longer period of time. This means many are deemed "cured."

I was successfully treated for MAC, then later diagnosed with Abscessus. Currently I’m experiencing weight loss and some new nodules have on my lung scans. My Infectious Disease doctor and I have decided to just watch how or if this infection progresses. How do you decide when to treat?

Generally we take several things into account when deciding whether to treat the NTM germs. First is whether the patient has symptoms that are advancing. Next we look at the CT scan, and how much disease is present. Generally if the disease is mostly located in one area of a lung we would consider surgery to remove that severely damaged area. If it is diffuse (throughout different parts of the lungs) we will consider medications and airway clearance. Lastly, we look at how positive the cultures are. If we can see a lot of them under the microscope it’s an indication that we need to get serious about treating the infection. If there aren’t enough germs to see but we can still culture them in the lab, we’ll look at how many colonies grow in the culture. Generally speaking, the greater the number of colonies, the larger burden of infection and therefore we need to more aggressively treat it.