Manur Rashmi, Lamzabi Ihab
Department of Pathology and Laboratory Medicine, Pennsylvania Hospital of the University of Pennsylvania Health System, Philadelphia, Pennsylvania.
Diagn Cytopathol. 2018 Jun;46(6):522-524. doi: 10.1002/dc.23877. Epub 2017 Dec 27.
Amyloidosis is a rare condition resulting from extracellular deposition of amyloid, a fibrillary material derived from various precursor proteins. Involvement of the pleura by amyloidosis is a rare but serious complication. Pleural amyloidosis is primarily diagnosed by identifying amyloid deposition by histology on pleural biopsy specimens. Hereby, we report a case of systemic amyloidosis where we were able to identify amyloid in a pleural effusion specimen sent for cytopathology evaluation. A 59-year-old male with newly diagnosed multiple myeloma and systemic amyloidosis underwent therapeutic thoracentesis. The H&E stained cell block sections revealed a single, less than one millimeter focus of waxy material surrounded by a rim of reactive mesothelial cells suspicious for amyloid deposit in a background of fibrin, lymphocytes, and reactive mesothelial cells. The focus stained salmon pink with Congo-red special stain and showed apple-green birefringence under polarized light. Our finding suggests that pleural involvement in patients with systemic amyloidosis can be identified on effusion specimens and avert the need for more invasive procedures like pleural or pulmonary parenchymal biopsies.
淀粉样变性是一种罕见的疾病，由淀粉样蛋白在细胞外沉积所致，淀粉样蛋白是一种源自各种前体蛋白的纤维状物质。淀粉样变性累及胸膜是一种罕见但严重的并发症。胸膜淀粉样变性主要通过对胸膜活检标本进行组织学检查以识别淀粉样蛋白沉积来诊断。在此，我们报告一例系统性淀粉样变性病例，在送检进行细胞病理学评估的胸腔积液标本中发现了淀粉样蛋白。一名新诊断为多发性骨髓瘤和系统性淀粉样变性的59岁男性接受了治疗性胸腔穿刺术。苏木精-伊红染色的细胞块切片显示有一个小于1毫米的蜡样物质单一病灶，周围是一层反应性间皮细胞，在纤维蛋白、淋巴细胞和反应性间皮细胞背景下，该病灶可疑为淀粉样蛋白沉积。该病灶经刚果红特殊染色呈鲑鱼粉红色，在偏振光下显示苹果绿双折射。我们的发现表明，系统性淀粉样变性患者的胸膜受累情况可在积液标本中得以识别，从而避免进行诸如胸膜或肺实质活检等更具侵入性的检查。
