Pulmonary haemorrhage

Bleeding may be due to localized or systemic diseases. Focal pulmonary haemorrhage is most commonly due to chronic bronchitis, bronchiectasis, pulmonary embolism, penetrating trauma, tumours or localized infections. The chest radiograph shows localized infiltrates, lobar consolidation, atelectasis, a mass and cavitation. CT is helpful and indicated in patients with haemoptysis in whom a focal abnormality is suspected.

Diffuse pulmonary haemorrhage (DPH) is characterized by haemoptysis, iron deficiency anaemia and diffuse pulmonary infiltrates on a chest radiograph. In an immunocompetent patient, the most common causes of DPH are antiglomerular basement membrane disease (Goodpastures syndrome), systemic vasculatides, (e.g. Wegeners granulomatosis chest, necrotizing capillaritis, microscopic polyarteritis), systemic lupus erythematosus, idiopathic pulmonary haemosiderosis, haemorrhagic diatheses, drug induced lung diseases (e.g. penicillamine, ethiodol, cocaine), and tumours (both primary and metastatic angiosarcoma). Most causes of DPH have characteristic extrapulmonary manifestations and associated serological abnormalities and are therefore diagnosed without lung biopsy. Idiopathic pulmonary haemorrhage is a chronic disease affecting only the lungs and characterized by repeated bouts of alveolar haemorrhage without glomerulonephritis or consistent serological abnormalities, and may result in pulmonary fibrosis within 5 years of presentation. In an immunocompromised patient with thrombocytopenia, DPH is frequently associated with underlying infections such as invasive aspergillosis, candidiasis and cytomegalovirus.

Radiographically, diffuse haemorrhage often results in confluent, poorly marginated air-space infiltrates or consolidation with bilateral perihilar predominance and a tendency to spare the lung apices (Fig.1). The airspace disease usually resolves within 2 - 3 days, being replaced by irregular reticular opacities reflecting interstitial disease. Ground glass attenuation, air space nodules and consolidation may be seen on CT scans. The T2-weighted MR images may show decreased signal intensity due to paramagnetic effects of ferric iron in the haemorrhage.

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