皮肤脂肪及直肠黏膜活检对诊断系统性轻链淀粉样变性的意义

The significance of skin fat and rectal mucosal biopsy in the diagnosis of systemic light chain amyloidosis

目的：分析我国汉族人群系统性轻链淀粉样变性（AL型淀粉样变性）的临床特征,比较不同部位活检对确诊的意义。方法：回顾性分析2009年1月至2014年10月在南京军区南京总医院肾脏科住院确诊的186例AL型淀粉样变性患者临床资料和病理诊断,以肾活检为诊断的金标准,比较皮肤脂肪活检和直肠黏膜活检对诊断AL型淀粉样变性的敏感性。结果：186例患者的平均年龄为（54.8±9.1）岁,男女比例为2.44∶1,143例（76.9%）的患者血清中检测出单克隆免疫球蛋白轻链。皮肤脂肪活检的诊断敏感性为92.5%,95%CI为88%～97%,直肠黏膜活检的诊断敏感性为94.9%,95%CI为92%～98%,结合皮肤脂肪和直肠黏膜两种活检方式,诊断阳性率达100%。结论：活检仍然是确诊AL型淀粉样变性的金标准,皮肤脂肪和直肠黏膜活检操作简单、花费低、并发症少且敏感性高,两种方法结合能够提高诊断的阳性率,对于难以进行肾活检的患者,皮肤脂肪和直肠黏膜是合适的活检取材部位。

Objective： To evaluate the skin fat biopsy and rectal mucosal biopsy in the diagnosis of AL amyloidosis. Methodology： One hundred eighty six patients diagnosed as AL amyloidosis from January 2009 to October2014 were included in this retrospective study. Using renal biopsy as the gold standard for diagnosis of AL amyloidosis,the diagnostic sensitivity between skin fat biopsy and rectal mucosal biopsy was compared. Results： There were 132 males and54 females with an average age of（ 54. 8 ± 9. 1） years old. Monoclonal immunoglobulin light chain was detectable in 143patients（ 76. 9%）. The sensitivity of skin fat biopsy and rectal mucosal biopsy was 92. 5% [95% CI 0. 88 ～ 0. 97] and94. 9%（ 95%CI 0. 92 ～ 0. 98）,respectively. The positive rate of diagnosis increased to 100% by the combination of the two biopsy methods. Conclusion： Tissue biopsy continues to be the gold standard for diagnosis of AL amyloidosis. Skin fat and rectal mucosal biopsies,being simple procedures with low cost and compliment,have acceptable sensitivities. Combination of both methods can improve the positive rate. Therefore,they are preferred biopsy site for patients unsuitable of renal biopsy.