Encyclopedia of Health and Medicine

202 The Pulmonary System
Symptoms and Diagnostic Path
The symptoms of cystic fibrosis vary according to
the body system first affected and usually appear
in childhood. Chronic productive COUGH, recurrent
bronchitis or pneumonia, and pronounced wheezing
are among the indications of pulmonary
involvement. The diagnostic path includes chest X-
rays and pulmonary function tests, which demonstrate
changes in lung structure and function
characteristic of cystic fibrosis. Other diagnostic
procedures look for nonpulmonary indications of
cystic fibrosis such as sinus disease, pancreatic disease,
decreased BONE DENSITY, and INFERTILITY. Family
history of cystic fibrosis provides strong
suspicion of the diagnosis. A positive sweat chloride
test and GENETIC TESTING that identifies cystic
fibrosis mutations. This provides conclusive diagnosis.
Treatment Options and Outlook
Treatment requires close coordination to target
symptoms and disease developments across body
systems. Pulmonary treatment aims to keep the
airways as open as possible and to prevent infection,
or treat infection early and aggressively.
IMMUNIZATION to protect against CHILDHOOD DISEASES
such as PERTUSSIS (whooping cough), CHICKENPOX,
and MEASLES are crucial, as are annual INFLUENZA
immunizations (flu shots) and pneumonia vaccination
every five years at all ages. CHEST PERCUS-
SION AND POSTURAL DRAINAGE help clear the airways
of mucus accumulations. Though coughing is a
frustrating symptom, it is also an important function
for removing mucus from the chest. Bronchodilators
help improve functioning of the
airways and removal of mucus from them.
Moderate to high doses of the NONSTEROIDAL
ANTI-INFLAMMATORY DRUG (NSAID) ibuprofen (Advil
or Motrin) taken regularly may slow bronchial
inflammation and damage in many people, especially
children. CORTICOSTEROID MEDICATIONS become
necessary when ibuprofen can no longer control
the inflammation or when inflammation becomes
widespread in the lungs. ANTIBIOTIC MEDICATIONS
become necessary to treat infections. People who
have cystic fibrosis commonly acquire antibioticresistant
bacteria, which may necessitate treatment
with more powerful intravenous antibiotics.
Inhaled antibiotic therapies are also becoming
available for treatment as well as prophylaxis (prevention).
Cystic fibrosis has numerous nonpulmonary
complications that also require close attention.
Dysfunction of the PANCREAS results in malabsorption
that may necessitate nutritional support. The
nature and severity of symptoms vary widely
among individuals. Cystic fibrosis is progressive,
however, and these treatments are only supportive.
When they fail, bilateral LUNG TRANSPLANTATION
is the final, though high-risk, treatment option.
Risk Factors and Preventive Measures
The only risk factor for cystic fibrosis is the recessive
gene mutation. Because this mutation is relatively
prevalent in the American population,
many people do not know they carry it until a
child develops the disease. Genetic testing and
GENETIC COUNSELING may be helpful for people who
have family histories of cystic fibrosis.
See also ANTIBIOTIC PROPHYLAXIS; ANTIBIOTIC RESIST-
ANCE; GENETIC DISORDERS; INHERITANCE PATTERNS;
ORGAN TRANSPLANTATION.
diaphragm The thin, flat MUSCLE that forms the
floor of the thoracic cavity (chest), establishing a
physical barrier between the thoracic cavity and
the abdominal cavity. Small openings in the
diaphragm allow structures such as the AORTA,
inferior VENA CAVA, and ESOPHAGUS to pass through.
The lower lobes of the LUNGS and the base of the
HEART rest against the diaphragm. The diaphragm
attaches to the lower ribs and spine in the back,
then rises along the back of the ribs to dome forward
to form the base of the thoracic cavity. Contraction
of the diaphragm tightens this dome,
pulling it downward to expand the thoracic cavity.
The diaphragm has two equal halves, each called a
hemidiaphragm, and is the primary muscle of
BREATHING.
Health conditions that can involve the
diaphragm include HIATAL HERNIA, in which weakness
in the musculature around the esophageal
opening allows the stomach to bulge upward
through the opening. Hiatal hernia typically
causes an uncomfortable burning sensation and
may result in regurgitating food or GASTROE-
SOPHAGEAL REFLUX DISORDER (GERD). HICCUPS are
muscle spasms of the diaphragm.