Making the Diagnosis
A doctor may suspect bronchiectasis because of symptoms, or because a person
has a condition related to it. X-rays can confirm the diagnosis and show
the location and extent of the damage, but may not always reveal it, however.
Bronchiectasis can usually be confirmed by high-resolution computed tomography
(CT scan).
Once bronchiectasis is diagnosed, a doctor will check for diseases causing
it. These tests may measure salt levels in the sweat to test for cystic
fibrosis, or measure immunoglobulin levels in the blood. Samples from the nose
or bronchi can show if the mucus-clearing cells are genetically defective. When
bronchiectasis has affected only a small area, doctors may thread a tiny camera
into the bronchi to see if a lung tumor or inhaled foreign object is the cause.
This procedure is called fiber-optic bronchoscopy. Other tests may be
done to see if someone has allergic bronchopulmonary aspergillosis, a
condition caused by a violent allergy to a kind of fungus. It causes a form
of bronchiectasis that affects the large bronchi.