Bronchial Pathology in Pulmonology

Overview

• Discussion on asthma, a significant bronchial disorder
• Key topics: airway obstruction, inflammation, mediators, genetics, exposures, triggers, comorbidities
• Focus: diagnosis, evaluation, therapy goals, and patient treatment

Asthma Pathology

• *Asthma Characteristics:
  • Primarily affects airways; lung parenchyma remains normal
• *Pathological Changes:
  • Chronic inflammation leads to airway hyper-responsiveness and obstruction

Inflammatory Process

• *Acute and Chronic Obstruction:
  • Acute: Direct smooth muscle agents
  • Chronic: Structural changes causing airway hyper-responsiveness
• *Role of Inflammatory Cells:
  • Chronic inflammation involves immune cells, leading to structural changes
• *Role of Mediators:
  • Multiple types including cytokines, fatty acid mediators, nitric oxide, etc.

Genetic and Environmental Factors

• *Exposure and Risk Factors:
  • Prenatal, childhood, and adulthood exposure
• *Common Exposures:
  • Allergens, viral infections, pollution, occupational hazards
• *Drugs and Pregnancy:
  • Certain medications can trigger asthma; pregnancy may have minimal risk

Diagnostic Approach

• *Primary and Adjunctive Tools:
  • History, physical examination, pulmonary function tests
• *Assessment of Airway Hyper-Responsiveness:
  • Methacholine challenge test, cold air provocation

Treatment Strategies

Overview

• *Avoiding Triggers:
  • Viral infections, allergens identified by patient
• *Medications:
  • *Reliever Medications:
    • Beta-2 agonists: Smooth muscle relaxation, reduced bronchospasm
    • Theophylline: Phosphodiesterase inhibitor
  • *Controller Medications:
    • Anti-inflammatory (corticosteroids, leukotriene modifiers)
    • *Newer Treatments:
      • Anti-IgE (Omalizumab)
• *Stepwise Treatment Plan:
  • Step 1: Short-acting bronchodilators as needed
  • Step 2: Regular low-dose inhaled corticosteroids
  • Step 3: Combination therapy (inhaled corticosteroids + long-acting beta agonists)
  • Step 4+: Increased dosage and additional therapies as needed

Special Considerations in Therapy

• *For Children and Adults:
  • Different prevalence in boys vs. girls (children), men vs. women (adults)
• Obesity:
  • Linked to higher asthma prevalence and more severe symptoms
• *Exercise-induced Asthma:
  • Triggered by cox-1 inhibition, safe use of paracetamol
• Managing Severe Cases:
  • Step 5 therapy involving high-cost biologics like Anti-IL-13 (e.g., Dupilumab)