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.)
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 and Guillain-Barré syndrome, 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.
When people have symptoms that suggest a lung disorder, doctors ask specific questions about the symptoms and other relevant factors (the medical history). Doctors usually also do a physical examination to evaluate all of the body systems, but they focus on the respiratory system. Depending on the results of the medical history and examination, diagnostic tests may be needed to confirm a diagnosis.