How is asbestosis diagnosed?
Diagnosis of asbestosis is largely dependent on a good and accurate clinical history taking. Occupational exposure to asbestosis is critical to the diagnosis. Histopathological diagnosis is usually not necessary for patient management but can be used to confirm the diagnosis. Screening of at-risk workers can reveal lung inflammation and lesions characteristic of
asbestosis. Patients' medical histories can identify occupations, hobbies, or other situations likely to involve exposure to asbestos fibers.
The person with asbestosis has abnormal lung function, and a doctor listening with a stethoscope placed over the lungs can hear abnormal sounds called crackles. In a person who has a history of exposure to asbestos, a doctor sometimes can diagnose asbestosis with a chest x-ray or a chest computed tomography (CT) that shows characteristic changes. X rays can show shadows or spots on the lungs or an indistinct or shaggy outline of the heart that suggests the presence of asbestosis. Blood tests are used to measure concentrations of oxygen and carbon dioxide. Pulmonary function tests can be used to assess a patient's ability to inhale and exhale, and a computed tomography scan (CT) of the lungs can show flat, raised patches associated with advanced asbestosis.
Pleural plaques that develop in many people with exposure to asbestos often contain calcium, which makes them easy to see on chest x-rays and CT. A lung biopsy is rarely needed to make the diagnosis. If a tumor of the pleura is found on x-ray, a doctor must perform a biopsy (remove a small piece of pleura and examine it under a microscope) to determine if it is cancerous.