Understanding Types of ILD
Dr. Zulma Yunt explains the different causes and risk factors for several types of interstitial lung diseases. These can include environmental exposures, autoimmune-related ILDs and idiopathic diseases with no clear cause.
Interstitial lung disease, or
ILD, refers to a group
or category of lung conditions.
It can be thought of as an umbrella term
that includes over 200 different diseases.
As the name implies,
interstitial lung disease
affects the interstitium of the lung.
The interstitium is a very thin tissue
that surrounds the alveolar air sacs
in the lungs and contains blood vessels
and other structures. In ILD,
the interstitium becomes infiltrated,
typically by inflammation, scarring,
or often both.
The presence of ILD is typically confirmed
with a CT scan.
Once ILD has been identified,
a pulmonologist
will aim to classify the ILD
and come up with a specific diagnosis.
Pulmonologists classify interstitial lung
disease largely based on their cause.
The majority of interstitial lung diseases
fall into one of three types of causes.
These are environmental
or occupational exposures,
autoimmune disease, or idiopathic causes,
which means they occur out of the blue
without a clear reason.
Interstitial lung disease
due to environmental exposures
include conditions like hypersensitivity
pneumonitis, asbestosis, silicosis,
and some smoking related diseases, amongst
many others.
Exposure to certain medications
and radiation therapy treatments
can also induce ILDs.
Your pulmonologists will likely ask
about various exposures
you've had, whether at home, at work
or traveling.
Smoking history and past medications
may also be reviewed.
Autoimmune disease
is another important cause of ILD.
The autoimmune conditions associated with ILD
are rheumatoid arthritis,
systemic sclerosis,
also known as scleroderma,
Sjogren's, myositis syndromes,
including dermatomyositis
and what is called antisynthetase
syndrome, and, less commonly, lupus.
Certain forms of autoimmune
vasculitis are also associated with ILD.
Please note that not everyone with these
autoimmune conditions will develop ILD,
but these specific conditions
do increase the risk.
Finally, idiopathic conditions are
perhaps among the most frequent
form of interstitial lung disease.
There are several conditions
that fall into this category,
but the most common of these is idiopathic
pulmonary fibrosis, or IPF.
IPF occurs
most often in people over the age of 60.
Sometimes IPF and other forms of
interstitial lung disease run in families.
While we are learning more
and more about all of the idiopathic ILDs,
it is still unclear
what causes their onset,
and most likely there are multiple
different factors that play a role.
Your pulmonologist will work with you
to find the best classification
for your specific condition.
ILD represents a journey,
and it is important
to develop a close working relationship
with your medical team.
Ask questions, educate yourself
and stay engaged with the process.