Microbiology Department, Counties Manukau Health, Auckland, New Zealand
Microbiology Department, Auckland District Health Board, Auckland, New Zealand.
J Clin Microbiol. 2018 Jul 26;56(8). doi: 10.1128/JCM.00258-18. Print 2018 Aug.
The challenges associated with diagnosing tuberculous pleural effusion have led to the use of pleural fluid adenosine deaminase (pfADA) as a biomarker for infection. This study retrospectively reviewed the diagnostic performance of pfADA, the pleural fluid lactate dehydrogenase (LD)/ADA ratio, and combinations of these two parameters in 1,637 episodes of pleural effusion in the low-tuberculosis (TB)-incidence setting of Auckland, Aotearoa New Zealand, from between March 2008 and November 2014. The median pfADA in 57 TB pleural effusion episodes (58.1 U/liter) was significantly higher ( < 0.001) than in 1,580 non-TB pleural effusions (11.4 U/liter). The median LD/ADA ratio in TB pleural effusion (8.2) was significantly lower ( < 0.001) than in non-TB pleural effusions (30.5). The pfADA and pleural fluid LD/ADA ratio AUC values (that is, receiver operating characteristic [ROC] curve analysis with determination of the ROC area under the curve) were 0.93 and 0.94, respectively. The pfADA thresholds of ≥15 and ≥30 U/liter demonstrated sensitivities of 100% (95% confidence internal = 93.7 to 100) and 93.0% (83.3 to 97.2), specificities of 62.7% (60.3 to 65.0) and 87.3% (85.6 to 88.9), positive predictive values (PPVs) of 8.8% (6.9 to 11.2) and 20.9% (16.4 to 26.4), and negative predictive values (NPVs) of 100% (99.6 to 100) and 99.7% (99.3 to 99.9), respectively. LD/ADA ratio thresholds of <25 and <15 demonstrated sensitivities of 100% (93.5 to 100) and 89.1% (78.2 to 94.9), specificities of 61.6% (59.1 to 64.0) and 84.8% (82.9 to 86.5), PPVs of 8.5% (6.6 to 10.9) and 17.3% (13.3 to 22.0), and NPVs of 100% (99.6 to 100) and 99.5% (99.0 to 99.8), respectively. A combination of pfADA ≥ 30 U/liter and an LD/ADA ratio < 15 increased the specificity and PPV to 97.8% (96.9 to 98.4) and 57.3% (46.5 to 67.5) but decreased the sensitivity to 85.5% (73.8 to 92.4). The primary value of pfADA in a low-TB-incidence setting, such as Auckland, is in utilization of its high NPV.
腺苷脱氨酶在结核性胸腔积液诊断中的应用面临挑战，因此人们将其作为感染的生物标志物。本研究回顾性分析了在新西兰奥克兰低结核病发病率环境下，2008 年 3 月至 2014 年 11 月期间 1637 例胸腔积液中腺苷脱氨酶（pfADA）、胸腔积液乳酸脱氢酶（LD）/ADA 比值以及这两个参数联合应用的诊断性能。57 例结核性胸腔积液的 pfADA 中位数（58.1 U/L）明显高于（<0.001）1580 例非结核性胸腔积液的 pfADA 中位数（11.4 U/L）。结核性胸腔积液的 LD/ADA 比值中位数（8.2）明显低于（<0.001）非结核性胸腔积液的 LD/ADA 比值中位数（30.5）。pfADA 和胸腔积液 LD/ADA 比值 AUC 值（即 ROC 曲线分析确定曲线下面积 AUC）分别为 0.93 和 0.94。pfADA 阈值≥15 U/L 和≥30 U/L 的敏感度分别为 100%（95%置信区间=93.7%至 100%）和 93.0%（83.3%至 97.2%），特异性分别为 62.7%（60.3%至 65.0%）和 87.3%（85.6%至 88.9%），阳性预测值（PPV）分别为 8.8%（6.9%至 11.2%）和 20.9%（16.4%至 26.4%），阴性预测值（NPV）分别为 100%（99.6%至 100%）和 99.7%（99.3%至 99.9%）。LD/ADA 比值阈值<25 和<15 的敏感度分别为 100%（93.5%至 100%）和 89.1%（78.2%至 94.9%），特异性分别为 61.6%（59.1%至 64.0%）和 84.8%（82.9%至 86.5%），PPV 分别为 8.5%（6.6%至 10.9%）和 17.3%（13.3%至 22.0%），NPV 分别为 100%（99.6%至 100%）和 99.5%（99.0%至 99.8%）。pfADA≥30 U/L 和 LD/ADA 比值<15 的联合应用可提高特异性和 PPV，分别达到 97.8%（96.9%至 98.4%）和 57.3%（46.5%至 67.5%），但敏感度降低至 85.5%（73.8%至 92.4%）。在奥克兰这样的低结核病发病率环境下，pfADA 的主要价值在于其高 NPV。
