Pulmonary amyloidosis presenting as lung cavitation with bronchiectasis: A case report

Amyloidosis is the extracellular deposition of amyloid fibril protein in any tissue or organ. Pulmonary amyloidosis is a localized form of amyloid deposition that is confined to the lung parenchyma and can cause airway obstruction, dysphagia, and chronic pleural effusions. When a 60-year-old female presented with chronic cough and recalcitrant pneumonias she was sent for imaging investigations and found to have cavitation with bronchiectasis of the right upper lobe. The patient subsequently underwent diagnostic bronchoscopy and bronchoalveolar lavage to obtain specimens for testing. Cytological evaluation revealed pulmonary amyloidosis in the area of cavitation, and the patient was diagnosed with a monoclonal gammopathy of unknown significance. Given her autoinnnnune hepatitis and her monclonal gammopathy, her amyloid sample was subtyped using laser capture microdissection, liquid chromatography, and tandem mass spectrometry, and the patient was found to have AL kappa type amyloidosis stemming from her monoclonal gammopathy. Given the localized extent of her amyloidosis, chemotherapy was deferred and close clinical follow-up was planned. This case of pulmonary amyloidosis demonstrates the utility of amyloid subtype analysis in clinically ambiguous situations to determine further workup and future follow-up.