Primary amyloidosis involving mediastinal lymph nodes: diagnosis by transbronchial needle aspiration.

Amyloidosis is an uncommon disease caused by the deposition of abnormal proteins within soft tissues. Pulmonary and mediastinal lymph node involvement of the disease is rare. When mediastinal lymph nodes are affected, the diagnostic approach should include sample collection for pathological examination. Transbronchial fine needle aspiration is a useful and safe procedure for sampling mediastinal lymph nodes. This paper describes the first case of amyloidosis that involves mediastinal lymph nodes diagnosed by transbronchial needle aspiration.