Pulmonary AL amyloidosis and multiple myeloma presenting as cough with diffuse pulmonary opacities.

Amyloidosis is an uncommon multisystem disease that can affect many organs. However, interstitial lung involvement is very rare. A 68-year-old man presented with long-standing dyspnoea and productive cough. After extensive investigation, including two non-diagnostic bronchoscopies, a surgical lung biopsy demonstrated pulmonary amyloidosis. A bone marrow biopsy confirmed multiple myeloma. The patient was treated with chemotherapy and an autologous stem cell transplant.