Virology Laboratory, Microbiology Department, Hospital Universitario 12 de Octubre, Madrid, Spain.
Nephrology Department, Hospital Universitario 12 de Octubre, Madrid, Spain.
Transpl Infect Dis. 2021 Aug;23(4):e13615. doi: 10.1111/tid.13615. Epub 2021 Apr 27.
This study focused on the role that BK polyomavirus (BKPyV) genotypes can play in the development of BKPyV-associated complications in renal transplant recipients.
A retrospective observational study (January 2015 to April 2018) was conducted by analyzing BKPyV genotypes in 180 blood samples with detectable BKPyV viral load (VL) > 1000 copies/mL, from 63 renal transplant recipients. VL and BKPyV genotypes detections were based on real-time PCR (rt-PCR)-specific assays.
Forty-four patients (44/63 [69.8%]) were men, and the median age was 55.0 (interquartile range 49.0-66.0 years). Eleven patients had clinical manifestations (11/63 [17.5%]). The most frequently detected genotypes were I (14/63 [22.2%]) and II (13/63 [20.6%]). Half of the patients (33/63 [52.4%]) had a mixed genotype, most with genotypes I and II (25/33 [75.8%]). Patients with infection by mixed genotypes showed VLs that were detected earlier (in the first year after transplantation) than those with a single genotype (25/33 [75.8%] vs 13/30 [43.3%], P = .009) and demonstrated greater risk of developing clinical manifestations associated with BKPyV (odds ratio 12.609, 95% confidence interval 1.503-105.807). Moreover, patients with first BKPyV VL > 10 000 copies/mL more frequently presented mixed genotypes (12/16 [75.0%] vs 21/47 [44.7%], P = .036).
The probability of developing clinical manifestations is higher in infections by mixed genotypes. Therefore, the detection of BKPyV genotypes by rt-PCR can provide relevant information to stratify patients' risk of BKPyV-associated complications and guide the clinical management of BKPyV infection in kidney transplant recipients.
本研究旨在探讨 BK 多瘤病毒（BKPyV）基因型在肾移植受者 BKPyV 相关并发症发展中的作用。
采用回顾性观察研究方法（2015 年 1 月至 2018 年 4 月），对 63 例肾移植受者中 180 份 BKPyV 载量（VL）>1000 拷贝/ml 且可检测到 BKPyV 的血样进行 BKPyV 基因型分析。VL 和 BKPyV 基因型检测基于实时聚合酶链反应（rt-PCR）特异性检测。
44 例（44/63 [69.8%]）患者为男性，中位年龄为 55.0（四分位距 49.0-66.0 岁）。11 例患者出现临床表现（11/63 [17.5%]）。最常检测到的基因型为 I 型（14/63 [22.2%]）和 II 型（13/63 [20.6%]）。一半的患者（33/63 [52.4%]）存在混合基因型，大多数为基因型 I 和 II（25/33 [75.8%]）。混合基因型感染患者的 VL 检测时间早于单基因型感染患者（移植后第 1 年：25/33 [75.8%] vs 13/30 [43.3%]，P=.009），且更易发生与 BKPyV 相关的临床表现（比值比 12.609，95%置信区间 1.503-105.807）。此外，首次 BKPyV VL>10000 拷贝/ml 的患者更常存在混合基因型（12/16 [75.0%] vs 21/47 [44.7%]，P=.036）。
混合基因型感染发生临床表现的概率更高。因此，rt-PCR 检测 BKPyV 基因型可为肾移植受者 BKPyV 相关并发症的风险分层提供相关信息，并指导 BKPyV 感染的临床管理。
