Department of Surgery, Providence Portland Medical Center, Portland, OR, USA.
Gastrointestinal and Minimally Invasive Surgery Division, The Oregon Clinic, 4805 NE Glisan St., Suite 6N60, Portland, OR, 97213, USA.
Surg Endosc. 2018 Feb;32(2):889-894. doi: 10.1007/s00464-017-5759-7. Epub 2017 Aug 4.
The gold standard for the objective diagnosis of gastroesophageal reflux disease (GERD) is ambulatory-pH monitoring off medications. Increasingly, impedance-pH (MII-pH) monitoring on medications is being used to evaluate refractory symptoms. The aim of this study was to determine whether an MII-pH test on medications can reliably detect the presence of GERD.
Patients referred for persistent reflux symptoms despite pH confirmed adequate acid suppression (DeMeester score ≤14.7) were reviewed retrospectively. All patients who originally had MII-pH testing on medications were re-evaluated with an off medication Bravo-pH study. Acid exposure results (defined by off medication Bravo) were compared to the original on medication MII-pH.
There were 49 patients who met study criteria (median age 51). Patients had normal acid exposure during their MII-pH test on medications (average DMS 4.35). Impedance was abnormal (normal ≤47) in 25 of the 49 patients (51%). On subsequent Bravo-pH off medications, 37 patients (75.7%) showed increased esophageal acid exposure (average DMS 36.4). Bravo-pH testing was abnormal in 84% of patients with abnormal MII testing and in 67% with normal MII testing. The sensitivity and specificity of an abnormal MII-pH on medications for increased esophageal acid exposure off medications was 56.8 and 66.7%, respectively. The positive predictive value of confirming GERD from an abnormal MII-pH on medications is 84%, while the negative predictive value is 33.3%. A receiver operating characteristic (ROC) curve was generated and the area under the curve was 0.71, indicating that MII-pH on medications is a fair test (0.7-0.8) in diagnosing pathologic GERD.
Compared to the gold standard, MII-pH on medications does not reliably confirm the presence of GERD. Excellent outcomes with antireflux surgery are dependent on the presence of GERD; thus, patients should not be offered antireflux surgery until GERD is confirmed with pH testing off medications.
胃食管反流病（GERD）客观诊断的金标准是停药物后的动态 pH 监测。阻抗-pH（MII-pH）监测在药物治疗下越来越多地被用于评估难治性症状。本研究旨在确定药物治疗下的 MII-pH 测试是否能可靠地检测 GERD 的存在。
回顾性审查因持续反流症状而被转诊的患者，尽管 pH 证实了足够的抑酸治疗（DeMeester 评分≤14.7）。所有最初接受药物治疗下的 MII-pH 测试的患者均重新接受 Bravo-pH 研究。对比停药物后的 Bravo 研究与最初的药物治疗下的 MII-pH 测试的酸暴露结果。
符合研究标准的患者有 49 例（中位年龄 51 岁）。患者在药物治疗下的 MII-pH 测试中酸暴露正常（平均 DMS 4.35）。在 49 例患者中有 25 例（51%）存在阻抗异常（正常<47）。在随后的 Bravo-pH 停药物后，37 例患者（75.7%）显示食管酸暴露增加（平均 DMS 36.4）。异常 MII 测试的患者中，84%的 Bravo-pH 测试异常，而正常 MII 测试的患者中，67%的 Bravo-pH 测试异常。药物治疗下异常 MII-pH 对停药物后食管酸暴露增加的敏感性和特异性分别为 56.8%和 66.7%。药物治疗下异常 MII-pH 确诊 GERD 的阳性预测值为 84%，阴性预测值为 33.3%。生成了一个接受者操作特征（ROC）曲线，曲线下面积为 0.71，表明药物治疗下的 MII-pH 是一种诊断病理性 GERD 的公平测试（0.7-0.8）。
与金标准相比，药物治疗下的 MII-pH 不能可靠地确认 GERD 的存在。抗反流手术的良好结果取决于 GERD 的存在；因此，在 pH 测试确认停药物后存在 GERD 之前，不应向患者提供抗反流手术。
