Pulmonary Alveolar Proteinosis, commonly known by the acronym PAP, is a
rare lung disease characterized by the build-up of grainy material in
the alveoli (air sacs) of the lungs. This grainy material is composed
mainly of phospholipid (a fat-like substance) and protein. Phospholipid
and protein are the key components of lung surfactant, an important
substance that coats the alveoli to prevent lung collapse and which
promotes oxygen absorption by the lungs.
In normal lungs,
specialized immune cells called alveolar macrophages swallow and remove
inhaled particles and excess surfactant from the alveoli. In the most
common form of PAP, it has been suggested that the alveolar macrophages
do not function properly and consequently cannot break-down and remove
the material they swallow. They become inefficient at clearing material
from the lungs.
In PAP patients, the accumulation of excess
surfactant material in the alveoli makes it increasingly difficult for
the lungs to absorb oxygen from inhaled air. This leads to breathing
difficulties such as shortness of breath and cough. Respiratory failure
may occur in severe cases. In addition to breathing problems, many PAP
patients acquire secondary infections, frequently caused by
opportunistic pathogens. Interestingly, some patients with the disorder
exhibit no symptoms.
PAP may progress in severity, remain
stable, or spontaneously clear. The lower and rear lung regions are
most commonly affected. Occasionally only the front segments of the
lungs may be involved.
Three forms of PAP are currently recognized: congenital, secondary,
and acquired. The congenital disease is most frequently diagnosed in
infants and is considered a genetic disorder that has been linked to
mutations in a gene encoding for a type of surfactant protein. In a
limited number of cases it has been linked to a defect in a growth
Secondary PAP is diagnosed in individuals who may exhibit a primary
disease that causes the alveolar macrophages to malfunction or reduces
the number of alveolar macrophages in the lungs.
Acquired PAP (also known as idiopathic PAP) is the most common form
of PAP, accounting for 90% of all cases. It is considered to be an
autoimmune disease in which an individual produces antibodies that
target an important growth factor for destruction by the immune system.
What’s New? The PAP Foundation is a newly established
organization dedicated to providing hope to all of those diagnosed with
Pulmonary Alveolar Proteinosis. We wanted to find a way to bring
together the patient community and the scientific and medical
communities to more effectively work in concert to find a way to cure
this sometimes debilitating and certainly frustrating disease!
PAP Foundation was conceptualized and established by Louie Schimpf and
Colleen Morrone, two individuals who are themselves PAP patients. The
formation of this Foundation was truly a labor of love for Louie and
Colleen, who decided to take action in the search for a cure after the
passing of their dear friend Joe Lopardo, who succumbed to the disease
in 2000. If Louie and Colleen’s names sound familiar to those in the
PAP community, it’s probably because they are the moderators of the PAP
Support Group on Yahoo! where they have been voices of support, caring,
and encouragement for several years now.
Since The PAP
Foundation and this website are brand new, we encourage your comments,
questions, and suggestions to help guide us as we work to bring you
news and information pertinent to PAP research, therapy, and support.