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Introduction to Diagnosis of Lung Disorders

By

Rebecca Dezube

, MD, MHS, Johns Hopkins University

Reviewed/Revised Nov 2023
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The respiratory system starts at the nose and mouth and continues through the airways and the lungs. Air enters the respiratory system through the nose and mouth and passes down the throat (pharynx) and through the voice box, or larynx. The entrance to the larynx is covered by a small flap of tissue (epiglottis) that automatically closes during swallowing, thus preventing food or drink from entering the airways. (See also Overview of the Respiratory System Overview of the Respiratory System To sustain life, the body must produce sufficient energy. Energy is produced by burning molecules in food, which is done by the process of oxidation (whereby food molecules are combined with... read more .)

Doctors may suspect a problem with the lungs or airways based on symptoms. Symptoms of lung disorders often affect breathing and may include

Symptoms that affect other parts of the body may also suggest a lung disorder is present. People with a lung disorder may have

Other, more general symptoms, such as fever, weakness, fatigue, or a general feeling of illness or discomfort (malaise), sometimes also reflect a lung or airway disorder. Some symptoms, such as cough or wheezing, may indicate a lung disorder. Disorders that affect the nerves or muscles, such as myasthenia gravis Myasthenia Gravis Myasthenia gravis is an autoimmune disorder that impairs communication between nerves and muscles, resulting in episodes of muscle weakness. Myasthenia gravis results from malfunction of the... read more and Guillain-Barré syndrome Guillain-Barré Syndrome (GBS) Guillain-Barré syndrome is a form of polyneuropathy causing muscle weakness, which usually worsens over a few days to weeks, then slowly improves or returns to normal on its own. With treatment... read more , cause weakness of the respiratory muscles and lung symptoms.

Respiratory symptoms may be minor (such as a cough caused by a cold) or life threatening (such as severe breathing difficulty).

The characteristics and pattern of symptoms help doctors diagnose the lung disorder.

NOTE: This is the Consumer Version. DOCTORS: VIEW PROFESSIONAL VERSION
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