Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
J Infect. 2020 Sep;81(3):443-451. doi: 10.1016/j.jinf.2020.07.003. Epub 2020 Jul 7.
Non-HIV immunocompromised patients with Pneumocystis jirovecii pneumonia (PCP) have lower fungal load than those with AIDS, potentially affecting the accuracy of diagnostic biomarkers. Therefore, we investigated the performance of serum (1,3)-Beta-d-Glucan (BDG) in conjunction with quantitative Pneumocystis jirovecii PCR (qPCR) in non-HIV cancer patients.
We reviewed records of non-HIV cancer patients and classified them as definite, probable, or possible PCP cases, according to clinicoradiological features, microscopy findings, and qPCR results in bronchoscopy specimens. We evaluated the diagnostic performance of serum BDG and its correlation with qPCR results.
We identified 101 PCP patients (73 definite/probable, 28 possible) and 74 controls. Correlation of BDG and qPCR was low among all 101 qPCR-positive patients (Spearman's = 0.38) and in definite/probable PCP cases (Spearman's = 0.18). Considering all qPCR-positive patients, BDG showed consistently low sensitivity at different cutoffs. Among definite/probable cases, the diagnostic accuracy of BDG remained poor, yet slightly improved with high qPCR thresholds (AUC = 0.86 at ≥2000 DNA copies/mL). BDG had a low PPV but excellent NPV across different qPCR and BDG cutoffs.
BDG and qPCR levels correlate poorly in non-HIV cancer patients with PCP. BDG diagnostic performance is suboptimal but a negative test may be useful to rule out PCP in this population.
与 AIDS 患者相比，非 HIV 免疫功能低下的卡氏肺孢子虫肺炎（PCP）患者的真菌负荷较低，这可能会影响诊断生物标志物的准确性。因此，我们研究了血清（1,3）-β-D-葡聚糖（BDG）与定量卡氏肺孢子虫 PCR（qPCR）联合在非 HIV 癌症患者中的表现。
我们回顾了非 HIV 癌症患者的记录，并根据临床放射学特征、显微镜检查结果以及支气管镜标本中的 qPCR 结果，将他们分为明确、可能的 PCP 病例。我们评估了血清 BDG 的诊断性能及其与 qPCR 结果的相关性。
我们确定了 101 例 PCP 患者（73 例明确/可能，28 例可能）和 74 例对照。在所有 101 例 qPCR 阳性患者中（Spearman's = 0.38）和明确/可能的 PCP 病例中（Spearman's = 0.18），BDG 与 qPCR 的相关性较低。考虑到所有 qPCR 阳性患者，BDG 在不同截点处的敏感性均较低。在明确/可能的病例中，BDG 的诊断准确性仍然较差，但随着 qPCR 阈值的升高略有改善（≥2000 DNA 拷贝/mL 时 AUC = 0.86）。BDG 在不同的 qPCR 和 BDG 截点下均具有较低的阳性预测值，但阴性预测值非常高。
BDG 和 qPCR 水平在非 HIV 癌症并发 PCP 的患者中相关性较差。BDG 的诊断性能不理想，但阴性检测可能有助于排除该人群中的 PCP。
