肾移植术后早期BK病毒感染的外周血淋巴细胞免疫特征分析

Immunological characteristics of peripheral blood lymphocytes infected with BK virus early after kidney transplantation

目的探讨同种异体肾移植术后患者早期外周血淋巴细胞的免疫特征,并以外周血淋巴细胞曲线下面积(area under the lymphocyte curve,L_AUC)作为免疫重建指标,研究其与肾移植术后早期BK病毒(BK virus,BKV)再激活的相关性。方法选择2020年1月至2021年10月期间,在复旦大学附属中山医院接受同种异体肾移植手术的患者,对最终符合纳入标准的共131例患者进行回顾性研究。根据肾移植术后患者外周血淋巴细胞计数及BKV-DNA载量,统计BKV感染情况,计算术后第1天到第30天的L_AUC。其中L_AUC定义为淋巴细胞计数-时间曲线下的一系列淋巴细胞计数之和。分析导致肾移植术后早期BKV再激活的危险因素,以及L_AUC与BKV再激活的相关性。结果131例肾移植患者中,共40例患者检测到BKV再激活,且均为BKV尿症。BKV激活组患者肾移植术后1个月内外周血中淋巴细胞计数明显低于BKV阴性组,术后30 d的L_AUC在两组患者间存在统计学差异。多因素回归分析显示,在对混杂因素进行较正后,低L_AUC(95%CI=1.416~8.726,P=0.007)被确定为肾移植术后早期BKV激活的独立危险因素,女性(95%CI=0.129~0.723,P=0.007)为肾移植术后早期BKV再激活的保护因素。结论外周血L_AUC与肾移植术后早期的BKV再激活相关,术后30 d内低L_AUC的肾移植患者更容易发生BKV的再激活。

Objective We retrospectively analyzed the immune characteristics of lymphocytes in patients with BK virus(BKV)activation after renal transplantation,and compared the impact of the areas under the lymphocyte curve(L_AUC)on BKV activation after renal transplantation.Methods Among 154 consecutive patients who underwent their first renal transplantation at our center between 2020 and 2021,a total number of 131 patients who met the inclusion criteria were retrospectively studied.We divided these patients into BKV negative group and BKV reactivation group based on the BKV-DNA load in urine and blood after renal transplantation.L_AUC was calculated as the area under the lymphocyte curve.We calculated L_AUC from day 0 to day 30.The risk factors for BKV reactivation and relationship with L_AUC in the early period after renal transplantation were analyzed.Results BKV activation was detected in 40 cases at six months after renal transplantation.The lymphocyte count was lower in BKV activation group than BKV negative group,and there was significant difference in L_AUC30 between the two groups.In a multivariate analysis,L_AUC30 was identified as an independent risk factor for BKV activation(95%CI=1.416~8.726,P=0.007),and female was a protective factor(95%CI=0.129~0.723,P=0.007).Conclusion L_AUC is associated with BKV activation after renal transplantation,patients with low L_AUC30 days after surgery are more likely to have BKV activation.