[Immune mediated intra-alveolar haemorrhage in the adult]

The diagnosis of diffuse intra-alveolar haemorrhage (DAH) is suggested by the combination of haemoptysis, anaemia and pulmonary infiltrates. Broncho-alveolar lavage produces macroscopically haemorrhagic fluid and/or haemosiderin laden macrophages. The diagnostic approach should allow distinction between immune mediated and other causes on account of the therapeutic implications.

The main immunological causes are small and medium vessel vasculitis (Wegener's granulomatosis, microscopic polyangeitis), lupus and Goodpasture's syndrome. Other immune disorders are only rarely involved. The association of DAH with an acute glomerulonephritis, indicating the pulmonary-renal syndrome, extra-thoracic involvement and immunological abnormalities suggest an immune aetiology. Immunosuppressant treatment should be started as soon as possible with corticosteroids often combined with intravenous cyclophosphamide. Plasmapharesis is indicated for Goodpasture's syndrome and poorly responding lupus. Aggravating factors such as hypervolaemia and disorders of haemostasis should be searched for and treated. Hospital mortality is close to 20%.

Immune mediated DAH is a disorder whose rarity justifies the establishment of a national registry with the aim of developing standardised diagnostic and therapeutic strategies.