A variety of illnesses are associated with coughing sputum, which is a mixture of mucus or phlegm from the lungs and saliva. Most common are the common cold, bronchitis, pneumonia, asthma, and allergies, although tuberculosis, cystic fibrosis, and a rare inherited disorder known as agammaglobulinemia also feature coughing sputum as a primary symptom. A cough that produces sputum is a consequence of an infection, normally caused by a virus or bacteria, that attacks the lungs and respiratory tract.
The common cold, which is caused by one of more than 200 varieties of cold virus, is an upper respiratory infection that often causes coughing sputum. It is usually accompanied by such symptoms as a sore throat, body ache, sinus congestion, and a runny nose and is treated with plenty of rest and fluids along with medication to ease symptoms. A cold may be followed by a bout of bronchitis, another type of respiratory infection that is characterized by coughing sputum. Bronchitis may be caused by bacteria attacking an already weakened immune system and causes fatigue, chest pain, shortness of breath, and sputum that is yellow-green if a bacterial infection is involved. If so, antibiotics may be required to eliminate the infection.
Another cause of coughing sputum is pneumonia, a contagious respiratory disease that can be caused by a variety of agents, from viruses to bacteria to fungi, though bacterial pneumonia is the most common. This disease causes yellow or yellow-green sputum, fever, chills, and shortness of breath, as well as headache and fatigue. Medical attention is usually required, and antibiotics are often prescribed.
Asthma and allergies are two very common causes of coughing sputum with similar symptoms but different causes. Asthma is a chronic inflammatory condition of the lungs and airways that, in addition to coughing, is characterized by wheezing, tightness in the chest, and an inability to catch one’s breath. Symptoms can be worsened by exposure to allergens in the environment, although allergies themselves are not related to inflammation of the airways. Rather, allergies involve the immune system identifying these allergens as harmful, much like bacteria and viruses, releasing chemicals known as histamines to fight them. The resulting symptoms depend on the type of allergen involved, but can present with the asthma-like symptoms of coughing sputum and wheezing, nasal symptoms, itchy and watery eyes, or skin reactions.
Less common causes of coughing sputum include more serious illnesses and disorders like tuberculosis, cystic fibrosis, and agammaglobulinemia. Tuberculosis is a serious, contagious lung disease caused by a bacterial infection and historically affecting millions of people worldwide. Cystic fibrosis is a hereditary condition that results in a chronic, dense accumulation of thick mucus in the lungs and gastrointestinal tract. Finally, agammaglobulinemia is another inherited disease, a rare disorder that is characterized by a lack of immunoglobulins, the proteins that protect the immune system, and that leaves sufferers especially vulnerable to bacterial lung infections like pneumonia.