【摘要】目的 对比分析原发性与继发性冷球蛋白血症肾损害患者的临床及肾脏病理特点，以提高对本病的认识。方法 回顾性分析2009～2017 年期间北京大学人民医院收治的35例经电镜证实的冷球蛋白血症肾损害患者的原发病、临床表现、实验室检查和肾脏病理检查等资料，总结冷球蛋白血症肾损害的特点并比较原发性与继发性冷球蛋白血症的异同。结果 35 例患者中继发性冷球蛋白血症23 例，原发性冷球蛋白血症12 例。2 组患者肾外受累均较少见(0～17.1%)，血清冷球蛋白的检测均存在一定的假阴性率(48.5%)，C3 降低较C4 降低更为常见。同原发性冷球蛋白血症相比，继发组以女性居多，补体水平更低、球蛋白更高。肾脏病理上继发组以多种免疫复合物沉积为主，而原发组有50%的患者表现为IgA肾病。结论 ①冷球蛋白血症的肾脏损害常发生于其他系统受累之前，且血清冷球蛋白的检测存在假阴性率，因此如果临床高度怀疑冷球蛋白血症而血清冷球蛋白试验阴性时，肾活检是协助诊断的手段之一。②无论是原发性还是继发性冷球蛋白血症患者的C3降低均非常明显，说明冷球蛋白可能不只通过经典途径激活了补体。③对于血清球蛋白显著升高、补体显著降低、肾脏病理显示以多种免疫复合物沉积为主的患者，需警惕继发性冷球蛋白血症可能。

【Abstract】Objective To analyze the clinicopathological characteristics in patients with essential and secondary cryoglobulinemia related glomerulonephritis (CGN). Methods A total of 35 patients diagnosed as CGN in Peking University People's Hospital during 2009-2017 were recruited. Their clinical and pathological data were investigated. Results Twenty-three CGN patients with specific causes were divided into secondary CGN group, and 12 patients without any underlying disease were divided into essential CGN group. Extra-renal manifestations were uncommon (0～17.1%) in both groups. The false negative rate of serum cryoglobulin was 48.5%. The decrease of C3 was more common than the decrease of C4. Compared with essential CGN group, more females, higher serum globulin level and lower serum complement levels were found in secondary CGN group. Multiple immune compound deposits were mainly seen in secondary CGN group. Half of the essential CGN patients had a renal pathology manifested as IgA nephropathy. Conclusion ①Since renal involvement in cryoglobulinemia often happened before other organ damages and the result of serum cryoglobulin may be false negative, renal biopsy is a useful tool to confirm the speculation especially to those with negative serum cryoglobulin. ②The decrease of C3 was commonly seen in both groups, indicating that cryoglobulin may not only activate complement by the classical pathway. ③Secondary CGN should be considered in patients with significantly higher globulin level, lower complement level and renal pathological changes characterized by multiple immune compound deposits.