Fogo A, Qureshi N, Horn R G
Department of Pathology, Vanderbilt University Medical Center, Nashville, TN 37232.
Am J Kidney Dis. 1993 Sep;22(3):367-77. doi: 10.1016/s0272-6386(12)70138-5.
Renal diseases characterized by Congo red-negative extracellular fibrillary deposits, either organized arrays of larger, microtubular fibrils (immunotactoid glomerulopathy [IT]) or smaller, randomly organized fibrils (fibrillary glomerulonephritis), have been recognized recently. The clinical significance, if any, of the distinction of these patterns has not been determined. On review of all renal biopsy specimens evaluated in a private referral renal pathology laboratory over the last 11 years, 26 cases with fibrillary glomerulonephritis pattern were identified and compared with our six most recent cases with the IT pattern. The fibrillary glomerulonephritis patients, 17 women and nine men, had an average age of 50 +/- 2 years and contributed 1% of the renal biopsy specimens examined. All patients had marked proteinuria and 16 had microscopic hematuria. Follow-up at 23 +/- 5 months in 25 of these patients revealed end-stage renal disease in 11 patients (44%) and one death due to renal failure. End-stage renal disease developed an average of 10 +/- 5 months after biopsy. One patient developed multiple myeloma. Twenty-four renal biopsy specimens showed proliferation, with crescents in seven. Immunofluorescence showed moderate to intense staining for immunoglobulin G and weaker staining for C3, in a predominantly mesangial pattern, with weaker glomerular basement membrane (GBM) staining, corresponding to electron microscopic deposit localization. In four cases, linear GBM staining by immunofluorescence corresponded to extensive subendothelial or transmembranous deposits. The average fibril diameter was 14.0 +/- 0.5 nm (range, 10.4 to 18.4 nm). Immunotactoid glomerulopathy patients (three women and three men) were significantly older, 62 +/- 2 years (P < 0.025). All had marked proteinuria, with microscopic hematuria in two patients. Associated hematopoietic diseases were present in four patients, with monoclonal proteins and/or abnormal plasma cell proliferation in three. One patient died of nonrenal causes. The remaining five patients have stable renal function at 20 +/- 5 months. Biopsy specimens showed proliferative (n = 3) or membranous-like (n = 3) patterns. Immunofluorescence showed immunoglobulin G and weaker C3 staining in a granular GBM pattern, with lesser mesangial staining. The microtubular fibril diameter was on average 43.2 +/- 10.3 nm (range, 16.8 to 90.0 nm). Thus, fibrillary glomerulonephritis and IT can be separated based on ultrastructurally distinct features. Patients with fibrillary glomerulonephritis are less likely than those with IT to have associated hematopoietic disease and also have poorer renal survival. We propose that classification based on these morphologic differences appears to have clinical significance.
以刚果红阴性细胞外纤维状沉积物为特征的肾脏疾病，即较大的微管纤维有组织排列（免疫触须样肾小球病[IT]）或较小的随机排列纤维（纤维性肾小球肾炎），最近已被认识。这些模式区分的临床意义（如果有的话）尚未确定。回顾过去11年在一家私人转诊肾脏病理实验室评估的所有肾脏活检标本，确定了26例纤维性肾小球肾炎模式的病例，并与我们最近的6例IT模式病例进行比较。纤维性肾小球肾炎患者中，17名女性和9名男性，平均年龄为50±2岁，占所检查肾脏活检标本的1%。所有患者均有明显蛋白尿，16例有镜下血尿。其中25例患者在23±5个月的随访中，11例（44%）发展为终末期肾病，1例死于肾衰竭。终末期肾病在活检后平均10±5个月出现。1例患者发展为多发性骨髓瘤。24份肾脏活检标本显示增殖，7份有新月体形成。免疫荧光显示免疫球蛋白G呈中度至强染色，C3染色较弱，主要呈系膜模式，肾小球基底膜（GBM）染色较弱，与电子显微镜下沉积物定位一致。4例中，免疫荧光显示的线性GBM染色对应广泛的内皮下或跨膜沉积物。平均纤维直径为14.0±0.5nm（范围为10.4至18.4nm）。免疫触须样肾小球病患者（3名女性和3名男性）年龄明显较大，为62±2岁（P<0.025）。所有患者均有明显蛋白尿，2例有镜下血尿。4例患者伴有造血系统疾病，3例有单克隆蛋白和/或异常浆细胞增殖。1例患者死于非肾脏原因。其余5例患者在20±5个月时肾功能稳定。活检标本显示增殖性（n = 3）或膜样（n = 3）模式。免疫荧光显示免疫球蛋白G和较弱的C3染色呈颗粒状GBM模式，系膜染色较少。微管纤维平均直径为43.2±10.3nm（范围为16.8至90.0nm）。因此，纤维性肾小球肾炎和IT可根据超微结构的不同特征进行区分。与IT患者相比，纤维性肾小球肾炎患者发生相关造血系统疾病的可能性较小，肾脏存活率也较低。我们认为基于这些形态学差异的分类似乎具有临床意义。
