Chen Xu-Tao, Chen Wen-Fang, Hou Xiao-Tao, Yang Shi-Cong, Yang Hui-Fei, Li Jun, Deng Rong-Hai, Huang Yang, Nuertai Yelidana, Wang Chang-Xi, Qiu Jiang, Huang Gang
Department of Organ Transplantation, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China.
Department of Pathology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, China.
Ann Transl Med. 2020 Mar;8(5):235. doi: 10.21037/atm.2020.01.15.
The positive predictive value (PPV) of urinary decoy cells for diagnosing BK polyomavirus associated-nephropathy (BKPyVAN) is low. This study was designed to increase the PPV of urinary decoy cells for diagnosing BKPyVAN in kidney transplant recipients.
A total of 105 urine sediment samples from 105 patients with positive BK viruria and decoy cells were evaluated by automatic double-immunostaining with anti-HGD (a renal tubular marker) antibody + anti-SV40-T antibody or anti-S100P (an urothelial marker) antibody + anti-SV40-T antibody.
Of the 105 patients, 76 (72.4%) had both HGD(+)/SV40-T(+) cells and S100P(+)/SV40-T(+) cells (group A), 24 (22.9%) had only S100P(+)/SV40-T(+) cells (group B), and 5 (4.6%) had only S100P(-)/HGD(-)/SV40-T(+) cells (group C). Seventy patients in group A (92.1%), 3 patients in group B (12.5%), and no patients in group C were diagnosed with BKPyVAN. The area under the ROC curve of predicting BKPyVAN by decoy cells was 0.531 (0.431-0.630), with an optimal cut-off value of 29 (per 10 high power field), a sensitivity of 45.8% (95% CI: 34.0-58.0%), and a specificity of 68.8% (95% CI: 50.0-83.9%). Besides, the area under the ROC curve of predicting BKPyVAN by plasma BKPyV load was 0.735 (95% CI: 0.632-0.822), with an optimal cut-off value of 1,000 copies/mL, a sensitivity of 61.1% (95% CI: 48.9-72.4%) and a specificity of 84.2% (95% CI: 60.4-96.6%). In contrast, the PPV, negative predictive value, sensitivity, and specificity of HGD(+)/SV40-T(+) cells for diagnosing BKPyVAN were 92.1% [95% confidence interval (CI): 83.0-96.7%], 89.7% (95% CI: 71.5-97.3%), 95.9% (95% CI: 87.7-98.9%), and 81.3% (95% CI: 63.0-92.1%) respectively.
Double-immunostaining with anti-HGD or anti-S100P and anti-SV40-T antibodies helps to identify the origin of decoy cells and diagnose BKPyVAN.
尿中诱饵细胞诊断BK多瘤病毒相关性肾病（BKPyVAN）的阳性预测值（PPV）较低。本研究旨在提高尿中诱饵细胞诊断肾移植受者BKPyVAN的PPV。
采用抗HGD（一种肾小管标志物）抗体+抗SV40-T抗体或抗S100P（一种尿路上皮标志物）抗体+抗SV40-T抗体自动双重免疫染色，对105例BK病毒尿和诱饵细胞阳性患者的105份尿沉渣样本进行评估。
105例患者中，76例（72.4%）同时有HGD(+)/SV40-T(+)细胞和S100P(+)/SV40-T(+)细胞（A组），24例（22.9%）仅有S100P(+)/SV40-T(+)细胞（B组），5例（4.6%）仅有S100P(-)/HGD(-)/SV40-T(+)细胞（C组）。A组70例（92.1%）、B组3例（12.5%）、C组无患者被诊断为BKPyVAN。诱饵细胞预测BKPyVAN的ROC曲线下面积为0.531（0.431 - 0.630），最佳截断值为29（每10个高倍视野），灵敏度为45.8%（95%CI：34.0 - 58.0%），特异度为68.8%（95%CI：50.0 - 83.9%）。此外，血浆BKPyV载量预测BKPyVAN的ROC曲线下面积为0.735（95%CI：0.632 - 0.822），最佳截断值为1000拷贝/mL，灵敏度为61.1%（95%CI：48.9 - 72.4%），特异度为84.2%（95%CI：60.4 - 96.6%）。相比之下，HGD(+)/SV40-T(+)细胞诊断BKPyVAN的PPV、阴性预测值、灵敏度和特异度分别为92.1%[95%置信区间（CI）：83.0 - 96.7%]、89.7%（95%CI：71.5 - 97.3%）、95.9%（95%CI：87.7 - 98.9%）和81.3%（95%CI：63.0 - 92.1%）。
抗HGD或抗S100P与抗SV40-T抗体双重免疫染色有助于识别诱饵细胞的来源并诊断BKPyVAN。
