肾移植患者尿小圆上皮细胞阳性指标与BK病毒尿症的临床相关性

Positive indicators of urine small round epithelial cells and their clinical correlation with BK viruria in renal transplant recipients

目的分析肾移植患者尿液中小圆上皮细胞(small round epithelial cells,SREC)阳性指标与BK病毒尿症的相关性。方法定期收集2017年1月至2019年10月的152名肾移植患者的尿液标本,检测尿SREC指标以及运用实时荧光定量PCR方法检测尿液标本中BKV-DNA拷贝数,并对检测结果进行分析评价。将BK病毒尿症患者的尿沉淀进行尿沉淀染色液和免疫荧光染色处理。结果36名(23%)BKV尿症患者发病时间为术后(2.5±0.5)个月,患者尿液标本里发现94%为SREC阳性指标,首次检测SREC阳性指标的中位时间为移植后(1.0±0.5)个月,SREC阳性指标以及SREC持续阳性时间段(the duration of SREC positivity,DSRECP)在BK病毒尿症患者的检测率高于非BK病毒尿症患者(P<0.05)。SREC持续阳性时间段能提前(1.0±0.5)个月预测BK病毒尿症发生,阳性预测值为94.44%,阴性预测值为85.34%。回归模型分析证实SREC阳性指标与阳性持续时间段可预测BK病毒尿症的发生不受干扰因素影响(P<0.05),ROC曲线中SREC阳性持续时间段在诊断BK病毒尿症的曲线下面积(AUC)为89.11%,cut-off值为85天,差异具有统计学意义。结论肾移植患者尿SREC阳性指标与BK病毒尿症具有显著相关性,可作为临床上早期预测并辅助诊断BK病毒尿症的潜在临床指标。

Objective To analyze the correlation between positive indicators of small round epithelial cells(SREC)in urine and BK viruria in renal transplantation recipients. Method A total of 152 renal transplantation patients’ urine samples from Jan 2017 to Oct 2019 were collected routinely.The urine small round epithelial cell indicators were detected,and real-time fluorescent quantitative PCR was used to detect the BKV-DNA test during the time of follow-up.Urine sediment specimens from renal transplant recipients with BK viruria were processed with urine sediment staining and immunofluorescence. Results Thirtysix(23%)patients with BK viruria time of onset was(2.5±0.5)months.94% of patients’ urine samples were positive for SREC.The median time for first detection of SREC positive indicators was(1.0±0.5)months after transplantation. The SREC positive indicators and the duration of SREC positivity(DSRECP) in patients with BK viruria was higher than that in non-BK viruria patients(P<0.05).DSRECP could predict the occurrence of BK viruria(1.0±0.5) months in advance,and the positive prediction value was 94.44%,and the negative predictive value was 85.34%. The immunofluorescence results confirmed that there BK viruria particles were in the cytoplasm of SREC,and the number of SREC was directly proportional to copy number of urine BKV-DNA,and the cell morphogenesis was different with Decoy cells. Regression model analysis confirmed that SREC positive indicators and DSRECP could predict the occurrence of BK viruria(P <0.05)without disruption. The area under the ROC curve(AUC)for the diagnosis of BK viruria for DSRECP in the ROC curve was 89.11%,and the cut-off value was 85 days,which was statistically significant. Conclusion Urine SREC in renal transplant recipients can predict the occurrence of BK viruria,and SREC potentially can be a clinical indicator for early clinical prediction and an aid to BK viruria.