Emphysema diagnosis consists of a physical examination, laboratory tests and imaging methods.
Emphysema diagnosis consists of a physical examination, laboratory tests and imaging methods. According to Johns Hopkins Health Information Library, of the estimated two million cases diagnosed in the United States, 90 percent are attributed to smoking and the remainder are due to a genetic disorder. Emphysema is typically a slowly progressive disease that does not cause symptoms until after the age of 50. However, the inherited form of emphysema frequently becomes symptomatic while patients are still in their 30s.
Emphysema is a lung disease that is caused by damage to the small air sacs in the lungs called alveoli. This damage restricts the airflow from the lungs while exhaling and results in shortness of breath. Since emphysema is so slow to develop, the symptoms may not be apparent until the damage is irreversible. When emphysema becomes more advanced, it becomes difficult to breathe even while resting.
According to the National Heart, Lung, and Blood Institute, most patients with emphysema seeking medical attention mention a slow development of breathlessness as the primary complaint. A persistent cough that produces mucus should also raise suspicion of emphysema. The doctor should take the patients medical history of smoking habits and any occupational exposure to other lung irritants, such as air pollution, chemical fumes or dust. The doctor should also investigate the possibility of an inherited form of emphysema by obtaining a family history of emphysema. The initial physical examination should include listening to the chest for abnormal sounds of respiration and prolonged exhalations. Other signs of emphysema include loss of appetite, weight loss, a barrel-chested appearance and bluish nail beds.
According to the Mayo Clinic, the most significant laboratory tests for emphysema are pulmonary function tests (PFTs), since they can detect emphysema before the patient notices any symptoms. These tests primarily measure the amount of air the lungs can hold and the air flow in and out of the lungs. PFTs may also be performed before or after a patient uses inhaled medications to measure their effectiveness. The PFT usually requires the patient to blow into an instrument called a spirometer.
Other laboratory tests for emphysema include an analysis of arterial blood gases which measure how effectively the lungs transfer oxygen into the bloodstream and remove carbon dioxide from the blood. A pulse oximetry test measures the amount of blood oxygen with a device is attached to the fingertip may be performed during different levels of activity. The cells in the sputum may also be examined to differentiate emphysema from other lung disorders.
Imaging studies are mainly used to make differential diagnoses of emphysema, according to UpToDate. A chest x-ray is normally performed to identify other lung diseases since only severe emphysema can be detected in this manner. A chest x-ray is rarely useful for diagnosing chronic bronchitis, but it may show mild scarring and airways with thickened walls. A computed tomography (CT) scan is a more specific and sensitive test for diagnosing emphysema and can accurately determine the size of air pockets in the lungs. This imaging technique may even be useful for assessing mild lung disease and evaluating surgical options.