Conditions in which surfactant levels are reduced

Conditions

• • Infant respiratory distress syndrome (IRDS)

    • Caused by lack of surfactant, commonly suffered by premature babies born before 28–32 weeks of gestation.

  • Hyaline membrane disease

    • An older term for IRDS

    • Based on the pathological findings at autopsy of premature infants. The hyaline membranes were proteinaceous material in the damaged alveoli.

• Congenital surfactant deficiency

• Pulmonary alveolar proteinosis

Relation to COPD

• • Biochemical surfactant abnormalities of varying degrees have been described in many lung diseases

  • Obstructive lung diseases

    • Asthma, bronchiolitis, chronic obstructive pulmonary disease, and following lung transplantation

  • Infectious and suppurative lung diseases

    • Cystic fibrosis, pneumonia, and human immunodeficiency virus

  • Adult respiratory distress syndrome

  • Pulmonary oedema

  • Diseases specific to infants

    • Chronic lung disease of prematurity

    • Surfactant protein-B deficiency

  • Interstitial lung diseases

    • Sarcoidosis, idiopathic pulmonary fibrosis, and hypersensitivity pneumonitis

  • Pulmonary alveolar proteinosis

  • Following cardiopulmonary bypass

  • Smokers

Treatment

• • For some pulmonary conditions surfactant replacement therapy is on the horizon

  • For the majority much more needs to be learnt about the pathophysiological role the observed surfactant abnormalities may have