Gokden Neriman, Barlogie Bart, Liapis Helen
Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA.
Ultrastruct Pathol. 2008 Jan-Feb;32(1):17-24. doi: 10.1080/01913120701854002.
Light-chain deposition disease (LCDD) of the kidney is defined as deposition of monotypic light chains (LC) within glomerular (GBM) and tubular (TBM) basement membranes. The morphologic features of pure renal LCDD have been presented only in case reports or small series. The aim of this study was to perform a comprehensive evaluation of the light (LM), immunofluorescence (IF), and electron microscopic (EM) features of pure renal LCDD in a large series of biopsies. Out of 46 cases assembled, 42 had multiple myeloma, 2 had monoclonal gammopathy of unknown significance, and in 2 patients no lymphoproliferative disease was identified. The most common LM lesion of LCDD, nodular glomerulosclerosis, was present in only 14 (30%) cases. GBM and/or TBM thickening was found in 3 (6%), mild to moderate mesangial matrix increase in 12 (23%), and unremarkable glomeruli and tubules were seen in 15 (32%) cases. Forty-two had IF and 40 (92%) showed characteristic linear LC immunoreactivity (24 kappa, 16 lambda) along GBM and/or TBM. Among 39 cases in which IF and EM was available, 25 (64%) were positive by both. Two (6%) were negative by IF, but had deposits by EM. In 12 (30%) with immunoreactivity to LC (4 kappa, 8 lambda), no deposits were identified ultrastructurally. This study shows heterogeneous LM lesions in pure LCDD cases. LM alone may be suspicious but not diagnostic of LCDD. Immunofluorescence is more sensitive than EM for detection of LC for the definitive diagnosis of LCDD. This study supports the importance of utilizing kappa and lambda stains in the routine IF panel for diagnosis of LCDD.
肾轻链沉积病（LCDD）定义为单型轻链（LC）沉积于肾小球基底膜（GBM）和肾小管基底膜（TBM）内。纯肾性LCDD的形态学特征仅在病例报告或小系列研究中有所描述。本研究的目的是对大量肾活检标本中纯肾性LCDD的光镜（LM）、免疫荧光（IF）和电镜（EM）特征进行全面评估。在收集的46例病例中，42例患有多发性骨髓瘤，2例患有意义未明的单克隆丙种球蛋白病，2例未发现淋巴增殖性疾病。LCDD最常见的LM病变为结节性肾小球硬化，仅14例（30%）出现。3例（6%）发现GBM和/或TBM增厚，12例（23%）出现轻度至中度系膜基质增多，15例（32%）肾小球和肾小管未见明显异常。42例进行了IF检查，40例（92%）显示沿GBM和/或TBM有特征性的线性LC免疫反应（24例κ型，16例λ型）。在39例同时进行IF和EM检查的病例中，25例（64%）两者均为阳性。2例（6%）IF检查为阴性，但EM检查有沉积物。12例（30%）对LC有免疫反应（4例κ型，8例λ型），超微结构未发现沉积物。本研究显示纯LCDD病例中LM病变具有异质性。单独的LM检查可能可疑，但不能诊断LCDD。免疫荧光在检测LC方面比EM更敏感，对LCDD的确诊有重要意义。本研究支持在常规IF检查中使用κ和λ染色对LCDD诊断的重要性。
