Pathophysiology
chronic irritation of bronchioles defined as cough and production of sputum on the majority of days in a 2 year period without any identifiable cause
Signs and Symptoms
1) cough 2) production of excess sputum 3) exertional dyspnea 4) cyanosis 5) cor pulmonale 6) edema 7) progressive hypoxemia 8) hypercapnia
Characteristic Test Findings
Laboratory – Reid’s index (measure of size increase in mucous glands) is > .5 (normal is < .5) Histology/Gross Pathology
1) hypertrophy of mucus-secreting glands 2) increased proportion of mucous cells to serous cells 3) thickened bronchial wall 4) increase in smooth muscle and chronic inflammation in submucosa 5) squamous metaplasia of bronchial epithelium
Associated Conditions
1) > 90% of patients are smokers and also have COPD 2) air pollution with inhalation of sulfur dioxide and particulate matter 3) cystic fibrosis 4) infections – Nocardia, Haemophilus influenzae, Streptococcus pneumoniae, adenovirus
Treatment
1) strict abstinence from smoking 2) antibiotics for pulmonary infections 3) bronchodilator drugs
Tips for USMLE
1) if a Reid’s index > 0.5 is mentioned, think bronchitis 2) if “blue bloater” is mentioned (cyanosis and edema associated with cor pulmonale), think bronchitis
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