Monitoring for cytomegalovirus (CMV)‐specific cell‐mediated immunity (CMV‐CMI) may be useful for individualizing valganciclovir (VGCV) prophylaxis after kidney transplantation (KT). We performed a commercial ELISA‐based interferon (IFN)‐γ release assay (QTF‐CMV) from posttransplant months 2‐5 (362 points) in 120 CMV‐seropositive KT recipients that received antithymocyte globulin as induction therapy and VGCV prophylaxis (median of 92 days). Forty‐seven patients (39.3%) had CMV infection after discontinuation of prophylaxis. The QTF‐CMV assay was reactive, nonreactive, and indeterminate in 264 (72.9%), 90 (24.9%), and 8 points (2.2%). The QTF‐CMV assay at prophylaxis discontinuation exhibited suboptimal accuracy for predicting protective CMV‐CMI (sensitivity: 77.4%; specificity: 34.3%; positive predictive value [PPV]: 64.1%; negative predictive value [NPV]: 50.0%), with no differences in 1‐year CMV infection rates between patients with negative (nonreactive or indeterminate) or reactive results (45.8% vs 36.1%; P  = .244). Specificity and PPV to predict protective CMV‐CMI improved by elevating the IFN‐γ cutoff value to 1.13 IU/mL (65.7% and 71.4%) and 7.0 IU/mL (85.7% and 76.2%), although NPVs decreased. The QTF‐CMV assay as per manufacturer's interpretative criteria performed poorly to predict protection from CMV infection following discontinuation of VGCV prophylaxis among ATG‐treated CMV‐seropositive KT recipients. This performance is slightly improved by modifying the IFN‐γ positivity threshold.

中文翻译：

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在用抗胸腺细胞球蛋白治疗的肾移植受者中使用基于 ELISA 的商业干扰素-γ 释放测定法监测 CMV 特异性细胞介导的免疫。

监测巨细胞病毒 (CMV) 特异性细胞介导免疫 (CMV-CMI) 可能有助于肾移植 (KT) 后个体化缬更昔洛韦 (VGCV) 预防。我们对 120 名接受抗胸腺细胞球蛋白诱导治疗和 VGCV 预防（中位数为92 天）。47 名患者 (39.3%) 在停止预防后出现 CMV 感染。QTF-CMV 检测在 264 (72.9%)、90 (24.9%) 和 8 个点 (2.2%) 中呈反应性、非反应性和不确定。预防性停药时的 QTF-CMV 检测在预测保护性 CMV-CMI 方面表现出次优准确性（灵敏度：77.4%；特异性：34.3%；阳性预测值 [PPV]：64.1%；P  = .244）。通过将 IFN-γ 截断值提高至 1.13 IU/mL（65.7% 和 71.4%）和 7.0 IU/mL（85.7% 和 76.2%），预测保护性 CMV-CMI 的特异性和 PPV 得到改善，尽管 NPV 有所下降。根据制造商的解释标准，QTF-CMV 检测在预测 ATG 治疗的 CMV 血清阳性 KT 接受者停止 VGCV 预防后的 CMV 感染保护方面表现不佳。通过修改 IFN-γ 阳性阈值，这种性能略有改善。