The bulk of past research into asthma has considered how the outer environment may affect individuals’ lungs. However, recently published research now suggests that both healthy and
unhealthy individuals present with microbiota in their lungs.
The study, which was published in
BMC Infectious Diseases, was a
case-control study of a total of 96 participants between the ages of 21-62. Of
those, 54 had asthma. All the participants received isotonic saline through an
ultrasonic nebuliser and were required to cough up globules of sputum. These
were then examined using a microscope. Researchers also used these samples to
extract DNA. The key results indicated that both cases and controls had a
larger than expected amount of fungi in their lungs and asthmatic patients had
the fungi Malassezia pachydermatis.
In total, 136 different species of fungi were found among the groups. Of those,
there were 46 that were more common among asthmatic patients and 90 that were
more common among healthy controls. This led the researchers to conclude that
fungi in the lungs is common among healthy individuals and that there is a need
for further studies to consider whether the pattern of lung fungi varies
between patients and controls.
Although this study was well
designed, there are a few areas that are worth improving. For instance, it is
clear that this study needs to be replicated using a larger and more
representative sample. It is also clear that using a fresh sputum sample would
have been more beneficial than delaying the analysis and subjecting the sample
to potential contamination from spores in the air. Lastly, if Malassezia pachydermatis were to be a
replicated finding, then it would be valuable to know whether any of those
participants also had pet dogs, as this is a type of fungi often found on their
skin.
Nevertheless, this study is
interesting because it changes the way we may imagine the lungs. Rather than
assuming that we are all born with clean lungs that get attacked from our
environment, it seems as if we already have microbiota in our system. This
opens up the possibility to see whether some microbiota are better at combating
harmful substances than others, and also whether some microbiotas make
individuals vulnerable to get certain infections if they are exposed to
particular kinds of environment. Moreover, understanding what specific
microbiota are involved in developing and maintaining asthma means there are
possibilities to develop more precise and efficient treatments.