Narrow-band imaging thoracoscopy in pleural amyloidosis.

We report the case of a 68-year-old male non-smoker suffering from shortness of breath for 1 year. He was referred to our institution for a definitive diagnosis. Both chest X-ray and computed tomography scans showed bilateral hydrothorax with no pleural thickening. We performed flexi-rigid thoracoscopic pleural biopsy on the right side with a single port under local anaesthesia. Multiple white nodules were seen in parietal and visceral pleura, and these nodules were small and flat under white light. Narrow-band imaging demonstrated pathognostic findings on parietal pleura. Irregular dilative vessels were seen around these nodules. Subsequently, we performed parietal pleural biopsy for these nodules. Pathological examination with haematoxylin and eosin staining revealed eosinophilic matrix material depositions present in the pleural parenchyma and the vessel wall. These depositions were positive for Congo red stain and showed apple-green birefringence under polarized light. These findings were compatible with pleural amyloidosis.