Bronchitis is an inflammatory disease that develops in the bronchioles of the lungs. There are two forms of bronchitis: acute and chronic. Acute bronchitis is a sudden illness that is of short duration. By contrast, chronic bronchitis is an inflammation that lasts three months or longer. Most symptoms of chronic bronchitis, including cough and mucus production, are caused by short-term and long-term effects of the inflammation.
Acute and chronic bronchitis differ in their causes and symptoms. Acute bronchitis generally is a complication of an upper respiratory tract infection, causing cough, mucus production, breathing difficulty, fatigue, fever, chest tightness and other respiratory symptoms for as long as several weeks. These symptoms are caused by infection, so they typically can be resolved with antibiotic or antiviral medication.
In contrast to the acute form of the illness, symptoms of chronic bronchitis are not caused by an infection and cannot be cured with antibiotics or antivirals. Instead, chronic bronchitis generally is the result of long-term inflammation or irritation such as that caused by cigarette smoking or environmental pollution. People with other respiratory diseases, such as emphysema, asthma, sinusitis or tuberculosis, have an increased risk of developing chronic bronchitis. In addition, acute bronchitis, if not treated adequately, can become a chronic version of the disease.
Common symptoms of chronic bronchitis include coughing, excessive mucus production, coughing up blood or bloody mucus, difficulty breathing or shortness of breath, frequent or recurring respiratory infection, wheezing, fatigue and headaches. People with chronic bronchitis often have a cough that becomes worse in damp weather, and they might have swelling of the ankles, feet and legs. In the short term, most symptoms are the result of excess mucus production, and as the disease progresses, chronic inflammation can cause the development of scar tissue in the bronchioles.
For a diagnosis of chronic disease, symptoms of chronic bronchitis must have been present for at least three months in two consecutive years. In addition, the symptoms must not have another discernible cause. To diagnose the condition, a doctor will take a medical history, including symptoms, and might order tests such as a lung function test, an arterial blood gas test, other blood tests, an exercise stress test and a chest X-ray or computed tomography (CT) scan.
Chronic bronchitis can lead to permanent lung tissue damage, and as such, it is not curable. There are treatments available that can alleviate the symptoms and improve the function of the lungs. If someone with chronic bronchitis is a smoker, the best thing he or she can do to manage the disease is to stop smoking. Medications to treat the condition include steroids to reduce inflammation and bronchodilators to open up the airways and make breathing easier.