Please wait while the transcript is being prepared...
0:00
JAKKO VAN INGEN: Hello, and
welcome to this next edition
in the Henry Stewart Talks
series on respiratory infections.
My name is Jakko van Ingen. I'm a
resident in clinical microbiology
at the Radbound University,
Nihmegen Medical Center, which
is a large university hospital
in the east of the Netherlands,
which hosts the National
Reference Clinic
for non-tuberculous
mycobacterial disease
and the National
Reference Laboratory
for laboratory diagnosis
of non-tuberculous
mycobacterial diseases.
Today, I would like to share
with you some of the recent data
and my own thoughts
on non-tuberculous
mycobacterial pulmonary
disease, focusing
on its diagnosis and management.
0:47
Any talk about
mycobacteria of course
has to start by mentioning
that in 1882, Robert Koch,
a German microbiologist,
found the causative agent
of human tuberculosis,
mycobacterium tuberculosis.
And immediately after this
finding, many researchers
started to look for the source
of tuberculosis in humans.
Because at that time,
it was not thought
that this was an infectious disease
that would spread human to human.
So people actually went
searching in a variety
of animals in the environment.
And then many of
those investigations
did turn up acid fast bacilli that
turned out to be mycobacteria.
And at the time because, by
their microscopic appearance,
they seemed to be a little different
from mycobacterium tuberculosis.
Many of them were dubbed atypical
mycobacterium tuberculosis.
And probably many of them were
non-tuberculous mycobacteria,
as they were found
in a lot of animals
that we now know harbor some
non-tuberculous mycobacteria,
like birds that are known
to carry mycobacterium
avium and mycobacterium genavense.
Or reptiles that are known to harbor
mycobacterium chelonae and the fish
that are known to harbor
mycobacterium marinum.
And in the environmental samples,
like basic water and soil samples,
a variety of
non-tuberculous mycobacteria
were found at the time.
It was only in the first five
decades of the last century
that sporadic case
reports of disease
caused by these atypical
mycobacteria started to emerge.
And at that time,
many of those strains
were given names,
referring to either
a patient or the localization
of where the patient
reported to his physician.
So it's unclear what
species they were.
So in 1953, Buhler and
Pollak for the first time
recorded clear-cut
lung disease caused
by a non-tuberculous mycobacterium.
In their tuberculosis
sanatorium, they
found that two patients
had a clinical disease that
resembled pulmonary tuberculosis.
But during their life, they
only excreted mycobacteria
in their sputum sample that turned
yellow if the cultures were exposed
to a light source, which is
something that mycobacterium
tuberculosis do not do.
And these patients did not respond
to their tuberculosis treatment,
and died.
And during autopsy, samples
from their lung lesions
were taken and again yielded these
yellow mycobacteria in culture
that we now know are
mycobacterium kansasii.
And that was actually the first
time that investigators realized
that these non-tuberculous
mycobacteria can
cause a tuberculosis-like
pulmonary disease.
And then it took up to the
1980s to discover that there was
another respiratory infection caused
by non-tuberculous mycobacteria
with a very different and very
distinct radiological presentation.
And that is the nodular
bronchiectatic lung disease
that I'll focus on some more later
on, a disease that at the time
was dubbed the Lady
Windermere syndrome.
And then also in the 1980s, the
non-tuberculous mycobacteria
in general got more attention,
because mycobacterium avium
was found to cause disseminated
disease in HIV/AIDS patients
with a very high mortality rate.