대한흉부영상의학회 Weekly Chest Cases

Diagnosis: Amyloidosis (nodular parenchymal)
Radiologic Findings: High-resolution CT images show bilateral nodules with irregular margins. Contrast CT scan with mediastinal window showed little enhancement. On PET/CT scan, nodules showed faint FDG uptake (mSUV 1.3). Needle biopsy was performed for a nodule in RLL. Histologic specimen showed extracellular amorphous eosinophilic material. Special stain with Congo red confirmed amyloidosis showing characteristic apple-green birefringence
Brief Review: There are three major forms of amyloidosis in the lower respiratory tract: tracheobronchial, nodular parenchymal and diffuse parenchymal. Although these forms can occuar in combination, in many cases the amyloid is deposited predominantly at one site. In addition to airway and pulmonary parenchymal disease, amyloidosis can also affect the hilar and mediastinal lymph nodes, pulmonary arteries, heart and diaphragm.

The parenchymal nodules of localized pulmonary amyloid can be solitary or multiple and usually fairy well defined. Calcification and ossification are relatively common. The nodular parenchymal form of amyloidosis is usually of amyloid type L and localized to the lung. Patients usually have no symptoms.
References: 1. NL Muller, CIS Silva. Imaging of the Chest. 872-875
Keywords: Lung, Connective tissue diseases, Storage and metabolic lung disease,

대한흉부영상의학회 Korean Society of Thoracic Radiology