Irritation of the airways by infections, inflammation, inherited disorders or structural abnormalities can cause increased mucus production and coughing up phlegm. Hair-like projections on the cells, lining the airways, move mucus up and out of the lungs. Heavy mucus production triggers the cough which assist in the expulsion of the excess mucus.
Pneumonia
Pneumonia is a viral, bacterial or fungal infection of the air sacs and supportive tissues of the lungs. The infecting agent and the immune system response to the infection cause airway inflammation with an associated increase in phlegm production. The phlegm or sputum is often thick and opaque, frequently with a yellow or greenish coloration. The National Heart, Lung and Blood Institute (NHLBI) notes that other symptoms of pneumonia include high fever, shaking chills and chest pain, precipitated by inspiration or coughing. The Centers for Disease Control and Prevention (CDC) reports 1.2 million Americans were hospitalized in 2006 with pneumonia.
Chronic Obstructive Pulmonary Disease
Chronic obstructive pulmonary disease (COPD) is a persistent, progressive lung condition most often caused by smoking, reports the American Academy of Family Physicians (AAFP). COPD includes chronic obstructive bronchitis and emphysema. Chronic irritation and inflammation of the airways associated with COPD causes markedly increased sputum production and persistent cough. According to CDC, an estimated 10 to 24 million people in the United States have COPD.
Cystic Fibrosis
Cystic fibrosis is an inherited disorder, which causes abnormally thick, sticky mucus. The Cystic Fibrosis Foundation notes that chronic cough is a characteristic symptom of cystic fibrosis as the lungs work to clear the abnormally thick mucus from the airways. The sputum coughed up is typically gel-like in consistency and is usually greenish or yellow in coloration. The NHLBI reports approximately 30,000 Americans have been diagnosed with cystic fibrosis.
Bronchiectasis
"The Merck Manual for Healthcare Professionals" explains that bronchiectasis is a condition in which the damage and dilation of the larger airways or bronchi occurs due to chronic infection and inflammation. This condition may be caused by cystic fibrosis, hypogammaglobulinemia and other immune deficiency disorders, rheumatoid arthritis, Sjögren's syndrome, tuberculosis and fungal infections of the lung. A characteristic symptom of bronchiectasis is coughing up large quantities of malodorous sputum. Coughing up blood also often occurs with this condition.
Pulmonary Edema
Pulmonary edema is usually a complication of heart failure. With heart failure, the heart is too weak to pump a normal volume of blood into the circulation. Like a vascular traffic jam, blood backs up in the lungs causing fluid leakage into the air sacs. This leads to marked shortness of breath and coughing up foamy sputum, reports the Mayo Clinic. The sputum may be streaked with blood. Pulmonary edema is a potentially life-threatening condition requiring immediate medical intervention.
References
- Merck Manual for Healthcare Professionals: Community-Acquired Pneumonia, Signs and Symptoms
- National Heart, Lung and Blood Institute: Pneumonia, Signs and Symptoms
- Centers for Disease Control and Prevention: Fast Stats on Pneumonia
- National Heart, Lung and Blood Institute: COPD, Signs and Symptoms
- American Thoracic Society: Signs and Symptoms of COPD
