Bronchitis%20-%20uncomplicated%20acute Signs and Symptoms

Uncomplicated Acute Bronchitis

• A self-limiting acute lower respiratory tract infection (LRTI) characterized by the sudden onset of cough with or without sputum production, in an otherwise healthy individual
• Diagnosis is based on clinical findings

Pathogenesis

• An inflammatory response to infections of the bronchial epithelium of the large airways of the lungs
  • Begins with mucosal injury, epithelial cell damage and release of proinflammatory mediators
  • Transient airflow obstruction and bronchial hyper-responsiveness
• Purulence can result from either bacterial or viral infection

Viral

• The most common cause (90% of cases) of bronchial inflammation in otherwise healthy adults presenting with acute bronchitis
  • Influenza A and B, parainfluenza 3 and respiratory syncytial virus produce primarily lower respiratory tract disease
  • Coronavirus, adenovirus and rhinoviruses more commonly produce upper respiratory tract symptoms

Non-viral

• Mycoplasma pneumoniae, Chlamydia pneumoniae, Bordetella pertussis (5-10% of cases)
  • B pertussis most likely to cause prolonged cough
• Environmental cough triggers (eg dust, dander, toxic fume inhalation)

Lower Respiratory Tract Infection (LRTI)

•  Cough and/or increase in sputum production
•  Breathlessness/wheeze
• Sweats and/or sore throat
• Increase in temperature

Typical Clinical Presentation of Uncomplicated Acute Bronchitis

• Predominant symptom: Cough with or without sputum production that persists for <3 weeks
  • The cough generally lasts 7-10 days but occasionally persists for >1 month
  • Influenza (flu) virus typically causes a nonproductive cough
  • If cough persists for >3 weeks, consider investigation of other diagnoses (eg tuberculosis in endemic areas)
• Sputum may be clear, white, yellow, green or even tinged with blood
  • Green/yellow (purulent) sputum production is indicative of an inflammatory reaction that can result from either viral or bacterial infection
• Cough may be accompanied by clinical features that suggest an acute respiratory tract infection (eg sore throat, rhinorrhea, hoarseness)
• Patient may also present with retrosternal chest pain on coughing, dyspnea, wheezing, fever, fatigue or night cough