Department of Pathology, Ohio State University, Columbus, USA.
Arch Pathol Lab Med. 2013 Sep;137(9):1304-8. doi: 10.5858/arpa.2012-0159-CR.
Amyloid light chain amyloidosis involving the kidneys is not uncommon in patients with monoclonal gammopathy. The mainstay of treatment of amyloid light chain amyloidosis is autologous hematopoietic stem cell transplantation. Evidence that the autologous hematopoietic stem cell transplantation has been successful is the absence of free monoclonal light chains in serum and urine. Herein, we report 2 cases of progressive renal amyloid light chain amyloidosis after autologous hematopoietic stem cell transplantation, documented by kidney biopsy, despite the absence of monoclonal protein in the serum and urine. Kidney function declined progressively in both patients. During that time, numerous immunofixation and protein electrophoresis test results were negative for monoclonal protein, both in serum and urine, concealing the progression of the amyloidosis. We conclude that close monitoring of kidney function is warranted following autologous hematopoietic stem cell transplantation in patients with amyloid light chain amyloidosis, even with negative results from monoclonal protein testing. Unexplained, worsening renal function warrants a kidney biopsy to assess whether retreatment of the monoclonal gammopathy is indicated.
肾脏受累的单克隆丙种球蛋白病相关的轻链淀粉样变并不少见。治疗轻链淀粉样变的主要方法是自体造血干细胞移植。自体造血干细胞移植成功的证据是血清和尿液中无游离单克隆轻链。本文报告了 2 例自体造血干细胞移植后进展性肾脏轻链淀粉样变的病例，尽管血清和尿液中均未检测到单克隆蛋白，但通过肾活检证实。这 2 例患者的肾功能均进行性下降。在此期间，多次免疫固定电泳和蛋白电泳检测结果均为阴性，血清和尿液中均未检测到单克隆蛋白，掩盖了淀粉样变性的进展。我们的结论是，即使单克隆蛋白检测结果为阴性，在自体造血干细胞移植后仍应密切监测轻链淀粉样变患者的肾功能。对于原因不明的、进行性恶化的肾功能，需要进行肾活检以评估是否需要重新治疗单克隆丙种球蛋白病。
