Now let's talk about the respiratory
disorders, bronchiolitis and RSV.
Bronchiolitis is a lower
respiratory tract infection.
The virus causes inflammation of the
small airways, the bronchioles.
Bronchiolitis occurs in
children <2 years old.
The inflammation partially or
completely blocks the airways,
sometimes, resulting in wheezing.
Due to the inflammation and
mucus produced by this disease,
less oxygen is available to be
exchanged, potentially causing hypoxia,
or decreased oxygen available
to reach the tissues.
Bronchiolitis is the leading
cause of hospitalization
in infants and young children.
So it's very important that the clinician
understands the disease process,
the signs and symptoms, and the
management of this disorder.
Viruses are the most common
cause of bronchiolitis.
And the most common virus
that causes bronchiolitis
is respiratory syncytial virus, or RSV.
It's a very common virus that affects
just about every child by the age of 2.
While the clinician does
not always test for RSV
when diagnosing a child with bronchiolitis,
the terms are often interchangeable
since it is the most common cause.
Bronchiolitis can also be
caused by other viruses,
including influenza, adenovirus,
and parainfluenza strains.
Unfortunately, infants can
be re-infected with RSV
because at least 2 strains
of the virus exist.
Fortunately, though, the subsequent
infections are usually milder.
Bacterial infections cause
bronchiolitis less frequently.
Culprits include <i>Mycoplasma pneumoniae</i>,
<i>Strep pneumonia</i>, and <i>Haemophilus influenza</i>.
While the viruses and bacteria that
cause bronchiolitis do not discriminate
and they can infect children of
all ages and states of health,
some children have risk factors
that increase their likelihood
of experiencing bronchiolitis.
These include prematurity, because
the lungs may be underdeveloped,
and this increases the likelihood of
respiratory illnesses and complications.
Children who are exposed
to second-hand smoke
and children who attend daycare as this
increases their exposure to other kids
who may also have RSV or bronchiolitis.
Children with an older sibling,
for the same reasons.
Children with a lung or heart defects.
Children who are immunocompromised,
and children who are not breastfed
as they're not receiving
these protective antibodies.
Hand hygiene can help decrease the
transmission of the viral droplets,
especially, prior to touching
your eyes, nose, and mouth,
which are the entry points for the virus.
Remember, bronchiolitis results in
inflammation of the bronchioles,
which are the smallest airways in the lungs.
The infection makes the bronchioles
swell and become inflamed.
To further complicate the matters,
mucus develops and then collects
in these small tiny airways,
making it difficult for the transportation
and exchange of air into
and out of the lungs.
On the top, you'll see normal,
clear, and open bronchiole tube.
Below, you'll see a bronchiole tube
in the setting of bronchiolitis.
The center of the airway is thickened,
decreasing the diameter
available for the airflow,
and the presence of mucus is going
to further complicate the situation.
The viruses and bacteria that cause
bronchiolitis are very easily spread.
Droplets are spread when someone who's
infected sneezes, coughs, or talks.
The droplets are then
picked up by the hands,
where they can survive and spread for
several hours onto objects or toys,
which are also known as fomites.
Imagine this in a daycare setting.
The infection will spread like wildfire.
Once a person touches the
contaminated shared object,
including the utensils, the toys,
doorknobs, counter tops, you name it,
they can easily acquire the infection by
then touching their eyes, nose, and mouth.
A patient with bronchiolitis is most
contagious early on in their illness,
and when a fever is present.
These patients should be isolated away from
other children until they're feeling better,
and they've been fever
free for at least 24 hours.