Epidemiology

• Seen mainly in Asia (mostly in Japan), few case reports in North America and Europe
• Not associated with smoking
• Usually occurs in males >40 y/o
• Associated With
  • Adult T-cell leukemia
  • Ulcerative Colitis

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Etiology

• Unknown

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Physiology

• Unclear
• Normal ciliary function
• Pseudomonas infection occurs late in disease course

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Pathologic Pattern

• Obliterative or proliferative BO may be seen
• Peribronchiolar mononuclear infiltrate involving entire wall of respiratory bronchiole (lumen filled with acute inflammatory cells: neutrophils)
• Intraalveolar foamy macrophages: within peribronchiolar alveolar septa
• Proximal bronchiectasis:

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Diagnosis

• PFT’s: obstructive pattern
• FOB: BAL reveals moderately increased WBC with neutrophilic predominance
  • Intraluminal acute inflammatory exudate usually represent superimposed bacterial infection
• CXR/Chest CT Patterns
  • Interstitial small nodular infiltrates (lower zone predominance) with hyperinflation:
• HRCT: panbronciolitis/ bronchiectasis/ small linear branching opacities/ small nodules in centrilobular areas
• Ig levels: normal

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Clinical

• Rapidly Progressive Airway Obstruction (see [[Obstructive Lung Disease]])
  • Dyspnea
• Chronic Sinusitis: typical

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Treatment

• Low-Dose Erythromycin
  • Dose: 200 mg PO qday
  • Marked improvement in symptoms and CXR (unclear mechanism)
• Steroids/Immunosuppressives: no role in this disease

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References

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