先前公布的数据已经证实,添加柠檬酸粉提高了13C-尿素呼气试验(13C-UBT)的准确性。然而,一些研究表明,柠檬酸测试餐可能是不必要的。因此,这项研究的目的是评估13C-UBT与柠檬酸餐的组合用于诊断中国人群中幽门螺杆菌(Hp)感染,特别是对于结果处于灰色地带的患者。在这项配对的自我对照研究中,所有受试者先前都接受了不含柠檬酸餐的13C-UBTs,并根据柠檬酸的不同剂量随机分为两组(低剂量柠檬酸组和高剂量柠檬酸组,包括含0.68克和3.84克柠檬酸粉的膳食,分别)。快速脲酶试验(CLO)阳性试验和组织学结果被认为是“金标准”。基线(DOB)值的平均增量,灵敏度,特异性,阳性预测值(PPV),比较两组的阴性预测值(NPV)和准确性,特别是对于结果处于灰色地带的患者。总的来说,对285名患者进行了测试。在这些病人中,189例纳入低剂量柠檬酸组,高剂量柠檬酸组包括96例。在没有柠檬酸的13C-UBT结果阳性的患者中[相对于基线(DOB)值≥4‰,n=174],无柠檬酸的13C-UBT结果为阴性(DOB值<4‰,n=111),8.0%(14/174)为假阳性,和0.9%(1/111)的假阴性确定的黄金标准。在14例假阳性患者中,78.6%(11/14)的假阳性在4-10‰的灰色区域。然而,柠檬酸在4-10‰的灰色区域没有假阳性13C-UBT结果。在商业13C-UBT与低剂量柠檬酸组中的13C-UBT的比较中,灵敏度,特异性,PPV,15分钟的净现值和准确度如下:99.1%vs.99.1%,97.5%vs.88.9%,98.2%vs.92.2%,98.8%与98.6%和98.4%vs.94.7%,分别。在4.0-10.0‰的灰色地带,在低剂量柠檬酸组中,商业13C-UBT与13C-UBT的比较,灵敏度,特异性,PPV,15分钟时的准确度如下:94.4%vs.100.0%,100.0%vs.0%,100.0%vs.75.0%和95.8%与75.0%,分别。在低和高剂量柠檬酸组的15-min和30-min测量间隔之间没有观察到显著差异,包括结果在灰色地带的患者。低剂量柠檬酸试验,最佳测量间隔为15分钟,在中国人群中,Hp感染的诊断非常准确,特别是对于结果处于灰色地带的个人。
Previous published data have confirmed that the addition of a citric acid meal improves the accuracy of the 13C-urea breath test (13C-UBT). However, some studies have suggested that a citric acid test meal may not be necessary. Thus, the aim of this study was to evaluate the combination of a 13C-UBT with a citric acid meal for the diagnosis of Helicobacter pylori (Hp) infection in a Chinese population, particularly for patients with results in the gray zone. In this paired self-controlled study, all subjects had previously undergone 13C-UBTs without citric acid meals and were randomly divided into two groups based on different doses of citric acid (a low-dose citric acid group and a high-dose citric acid group, comprising meals with 0.68 g and 3.84 g citric acid powder, respectively). Positive rapid urease test (CLO) test and histology results were considered the \'gold standard\'. The mean delta over baseline (DOB) value, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were compared between the two groups, particularly for patients with results in the gray zone. In total, 285 patients were tested. Of these patients, 189 were included in the low-dose citric acid group, and 96 were included in the high-dose citric acid group. Among patients with a positive 13C-UBT result without citric acid [delta over baseline (DOB) value ≥ 4‰, n = 174] and a negative 13C-UBT result without citric acid (DOB value < 4‰, n = 111), 8.0% (14/174) were false positive, and 0.9% (1/111) was false negative as determined by gold standard. Of 14 patients with false positive, 78.6% (11/14) false positive were in the gray zone of 4-10‰. However, there were no false positive 13C-UBT results with citric acid in the the gray zone of 4-10‰. In the comparison of the commercial 13C-UBT with the 13C-UBT in the low-dose citric acid group, the sensitivity, specificity, PPV, NPV and accuracy at 15 min were as follows: 99.1% vs. 99.1%, 97.5% vs. 88.9%, 98.2% vs. 92.2%, 98.8% vs. 98.6% and 98.4% vs. 94.7%, respectively. In the the gray zone of 4.0-10.0‰, the comparison of the commercial 13C-UBT with the 13C-UBT in the low-dose citric acid group, the sensitivity, specificity, PPV, and accuracy at 15 min were as follows: 94.4% vs. 100.0%, 100.0% vs. 0%, 100.0% vs. 75.0% and 95.8% vs. 75.0%, respectively. No significant difference was observed between the 15-min and 30-min measurement intervals in the low- and high-dose citric acid groups, including patients with results in the gray zone. The low-dose citric acid test, with an optimal measurement interval of 15 min, was highly accurate in the diagnosis of Hp infection in the Chinese population, especially for individuals with results in the gray zone.