[Domestic hypersensitivity pneumonitis]

Abstract

Introduction: Domestic hypersensitivity pneumonitis (HP) cases are relatively widespread, with an overall annual incidence of approximately 1/100,000 reported in a British study covering several million patients. All-causes mortality is three times higher within HP-affected patients than amongst the general population.

State of the art: Cases of HP are usually diagnosed as 'farmer's lung' (FL) and 'bird fancier's lung' (BFL) diseases, however we suggest that other domestic causes, such as humidifier lung, hot tub pneumonitis, feather duvet and domestic exposure to moulds may be more frequent than widely suggested. Usually, the diagnosis is established on the basis of characteristic clinical, functional, radiological and broncho-alveolar lavage findings or recurrence of respiratory symptoms after returning home.

Perspectives: In the absence of a common cause (FL or BFL), physicians must have a high index of clinical suspicion and should consider an environmental antigen source. Detailed questioning of HP patients on their living conditions and, where appropriate, a home inspection conducted by an environmental health expert are necessary for identifying causative antigens.

Conclusion: The cornerstone of therapy is antigen avoidance.