Chronic bronchitis is a common disorder that becomes increasingly debilitating as it progresses. It is defined when an individual has had a cough with sputum for 3 months in 2 successive years. It is a progressive inflammatory disease resulting from prolonged irritation of the bronchial epithelium.
PREDISPOSING FACTORS.
1)Cigarette smoking.
2) Acute bronchitis caused by haemophilus influence or strep occurs pneumoniae.
3)Atmosphere pollutants eg motor vehicle exhaust fumes,chemicals.
4)Previous episodes of acute bronchitis.
CHANGES OCCURRING IN THE BRONCHI.
1) Increased size and number of mucus glands.
These block small airways and overwhelm the ciliary escalator,leading to reduced clearance,a persistent cough and infection.
2)Oedema and other inflammatory changes.
These cause swelling of the airway wall,narrowing the passageway and obstructing airflow.
3)Reduction in number and function of ciliated cells.
As ciliary efficiency is reduced,the problem of mucus accumulation is worsened,further increasing the risk of infection.
4)Fibrosis of the airways.
Inflammatory changes lead to fibrosis and stiffening of airway walls,further reducing airflow.
