Lung
Obstructive pulmonary disease
Chronic bronchitis
Author: Elliot Weisenberg, M.D.
Last author update: 1 August 2011
Last staff update: 17 July 2020
Copyright: 2003-2025, PathologyOutlines.com, Inc.
PubMed search: chronic bronchitis [title] lungs copd
Table of Contents
Definition / general | Clinical features | Gross description | Microscopic (histologic) description | Microscopic (histologic) imagesCite this page: Weisenberg E. Chronic bronchitis. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/lungnontumorchronicbronchitis.html. Accessed April 2nd, 2025.
Definition / general
- Diagnosis: persistent cough with sputum for 3 months in 2 consecutive years without other apparent explanation (eMedicine)
- Chronic disease of large airways, variable inflammation
Clinical features
- Simple chronic bronchitis: cough but no physiologic evidence of airway obstruction
- Chronic asthmatic bronchitis: hyperreactive airways with intermittent bronchospasm and wheezing
- Obstructive bronchitis: often have associated emphysema, small airway disease
- Causes: 4× - 10× more common in smokers, chronic irritation and infections may contribute
- Other causes and contributors are air pollution including passive cigarette smoke, marijuana smoke and occupational dust exposure
- Tobacco interferes with ciliary action, directly damages airway epithelium and inhibits ability of white blood cells to clear bacteria; infections maintain but do not initiate chronic bronchitis
- Often diagnosed at time of acute respiratory illness (Prim Care Respir J 2010;19:371)
- More infections, purulent sputum, hypercapnia, hypoxia than emphysema; clinically called "blue bloaters"
- May cause secondary pulmonary vascular hypertension, cor pulmonale, congestive heart failure, death due to respiratory acidosis and coma, congestive heart failure and pneumothorax
- Reid index: ratio of thickness of mucus gland layer to thickness of wall between epithelium and cartilage; normal is 0.4, increased in chronic bronchitis
Gross description
- Boggy mucosa with excessive mucinous secretions, pus, prominence of bronchial mucosal pits overlying the orifices of bronchial mucous glands
Microscopic (histologic) description
- Early: hypersecretion of mucus in large airways with hypertrophy of submucosal glands in tracheobronchial tree
- Later: increase in goblet cells in small airways contributes to excessive mucus production and airway obstruction
- Increased percentage of bronchial wall is occupied by submucosal mucous glands, as measured by Reid index; this directly correlates with sputum production, variable dysplasia, squamous metaplasia, bronchiolitis obliterans
- Chronic inflammatory infiltrates range from absent to prominent
Microscopic (histologic) images
Images hosted on other servers:
Mucosal glandular hyperplasia
Chronic inflammatory infiltrate
