Institute of Virology, University of Cologne, Cologne, Germany.
National Reference Center for Papillomaviruses and Polyomaviruses, University of Cologne, Cologne, Germany.
Med Microbiol Immunol. 2015 Dec;204(6):657-64. doi: 10.1007/s00430-015-0398-x. Epub 2015 Mar 7.
Polyomavirus BK (BKPyV) is ubiquitous among humans. Following primary infection, the virus remains latent predominantly in the hosts' uroepithelial cells. Up to 10 % of renal transplant recipients show a viral reactivation that can lead to polyomavirus-associated nephropathy (PyVAN). In the absence of early treatments, the risk of graft loss is up to 80 %. Monitoring viral load in urine and plasma by real-time PCR after transplantation is the most common diagnostic tool to detect viral reactivation. In the present retrospective study, BKPyV-DNA loads in urine and plasma by quantitative real-time PCR were associated with clinical data, including HLA haplotype, blood parameters and viral genotype, of 40 renal transplant recipients at the University Clinics of Cologne. Seventeen out of 329 patients screened for BKPyV from January 2009 to October 2013 were detected BKPyV positive in urine only, whereas in 23 patients the virus became additionally detectable in plasma. Among these, ten patients progressed to PyVAN. Overall, the present study showed that the detection from the third month onwards after transplantation of a first viruric episode with a median viral load of 1 × 10(8) copies/mL, followed after few days by a first viremic episode with a median viral load of >1 × 10(4) copies/mL, was strongly associated with the development of PyVAN. In conclusion, the viral load and the temporal profile of the first viruric and viremic episode post-transplantation, in combination with specific features of the host immune response, should be considered as relevant clinical determinants of the risk of renal transplant recipients to progress to PyVAN.
多瘤病毒 BK（BKPyV）在人类中普遍存在。原发性感染后，病毒主要潜伏在宿主的尿路上皮细胞中。多达 10%的肾移植受者出现病毒再激活，可导致多瘤病毒相关性肾病（PyVAN）。如果不进行早期治疗，移植肾丢失的风险高达 80%。移植后通过实时 PCR 监测尿液和血浆中的病毒载量是检测病毒再激活的最常用诊断工具。在本回顾性研究中，对科隆大学附属医院 40 例肾移植受者的临床资料（包括 HLA 单倍型、血液参数和病毒基因型）与定量实时 PCR 检测的尿液和血浆 BKPyV-DNA 载量进行了关联分析。在 2009 年 1 月至 2013 年 10 月筛查的 329 例患者中，有 17 例仅在尿液中检测到 BKPyV 阳性，而在 23 例患者中，病毒在血浆中也可检测到。其中，10 例患者进展为 PyVAN。总的来说，本研究表明，在移植后第三个月开始检测到首次病毒血症，病毒载量中位数为 1×10(8)拷贝/mL，随后几天内首次病毒血症，病毒载量中位数>1×10(4)拷贝/mL，与 PyVAN 的发生密切相关。总之，病毒载量和移植后首次病毒血症和病毒血症的时间谱，结合宿主免疫反应的特定特征，应被视为肾移植受者进展为 PyVAN 的相关临床决定因素。
