Beirão Idalina, Moreira Luciana, Porto Graça, Lobato Luísa, Fonseca Isabel, Cabrita António, Costa P M P
Centro de Estudos de Paramiloidose, Department of Nephrology, Santo António General Hospital, Porto, Portugal.
Nephron Clin Pract. 2008;109(2):c95-9. doi: 10.1159/000142527. Epub 2008 Jul 3.
Anemia with low serum erythropoietin (EPO) is common in Portuguese transthyretin V30M amyloid polyneuropathy (FAP). Low EPO production can be observed before clinical disease. Renal amyloidosis is observed in FAP, mainly in the medulla. Renal manifestations correlate with glomerular and vascular involvement, but not with tubulointerstitial deposition. To evaluate the potential role of renal amyloid deposits in the genesis of the EPO defect in FAP, we analyzed the renal biopsies of 12 patients (5 males, 7 females, aged from 29 to 54 years) with a clinical evolution varying from 3 to 12 (mean 5.4 +/- 2.8) years.
Formalin-fixed, paraffin-embedded sections of renal biopsies were stained by Congo red. Amyloid deposits were assessed by a semiquantitative method based on the percentage of amyloid deposition in each renal structure. Hemoglobin, creatinine, urea, EPO and proteinuria were concomitantly evaluated and correlated with the pathological findings.
Renal amyloid deposits were observed in all biopsies analyzed, independently of the neuropathy score. Low serum EPO levels were not related with either the amount of amyloid deposition or the renal clinical manifestations.
Impairment of EPO production in FAP is not directly related to renal amyloid deposits and more studies are needed to clarify this question.
血清促红细胞生成素（EPO）水平低的贫血在葡萄牙转甲状腺素蛋白V30M淀粉样多神经病（FAP）中很常见。在临床疾病出现之前就能观察到EPO生成减少。FAP中可见肾淀粉样变性，主要位于髓质。肾脏表现与肾小球和血管受累相关，但与肾小管间质沉积无关。为了评估肾脏淀粉样沉积物在FAP中EPO缺陷发生过程中的潜在作用，我们分析了12例患者（5例男性，7例女性，年龄29至54岁）的肾脏活检标本，其临床病程为3至12年（平均5.4±2.8年）。
肾脏活检标本经福尔马林固定、石蜡包埋后，用刚果红染色。淀粉样沉积物采用基于每个肾脏结构中淀粉样沉积百分比的半定量方法进行评估。同时评估血红蛋白、肌酐、尿素、EPO和蛋白尿，并将其与病理结果进行关联分析。
在所有分析的活检标本中均观察到肾脏淀粉样沉积物，与神经病变评分无关。血清EPO水平低与淀粉样沉积量或肾脏临床表现均无关。
FAP中EPO生成受损与肾脏淀粉样沉积物无直接关系，需要更多研究来阐明这一问题。
