Abstract
Background. Amyloidosis is a metabolic disease of unknown cause where amyloid protein is deposited in internal organs. When amyloid protein is localized in the respiratory tract, it is called "primary pulmonary amyloidosis", although it rarely occurs. Case. A 78-year-old man was found to have a 3.3cm in diameter nodule with a clear margin and a swollen lymph node, forming a mass at the right hilum, on a routine examination in February, 2005. The nodule was uniform, without calcification or cavitation. Fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) revealed increased accumulation in the nodule. Bronchoscopy revealed a submucosal elevation in the right truncus intermedius. We diagnosed this case as amyloid L (AL) type amyloidosis based on the transbronchial biopsy specimen. No deposits of amyloid protein were noted in other internal organs. These findings confirmed the diagnosis of localized nodular pulmonary amyloidosis. Conclusion. We report a case of localized nodular pulmonary amyloidosis diagnosed by transbronchial biopsy.
