Department of Gastroenterology, Mongolian National University of Medical Sciences, Ulaanbaatar, Mongolia.
Endoscopy Unit, Mongolia-Japan Hospital, Mongolian National University of Medical Sciences, Ulaanbaatar, Mongolia.
Helicobacter. 2021 Jun;26(3):e12790. doi: 10.1111/hel.12790. Epub 2021 Feb 17.
16S rRNA amplicon sequencing is an accurate method of detecting microbial infection without culture. It is unclear if sequencing has additional benefits over routine diagnostic methods for Helicobacter pylori testing.
We enrolled Mongolian volunteers with dyspepsia. Using routine diagnostic methods, positive H. pylori was defined as positive results on histology/immunohistochemistry, culture, rapid urease test, or serology; negative H. pylori was defined by negative results from all these tests. We performed 16S rRNA sequencing on gastric biopsy specimens and calculated cutoffs for operational taxonomic units (OTUs) and relative abundance (RA) to define positive results using ROC curves.
We examined 161 individuals with a mean age of 43.6 years, and 64.6% were women. Using routine diagnostic methods, 122 (75.8%) participants were H. pylori positive, the sensitivity and specificity for 16S rRNA sequencing were 94.3% and 82.1% or 93.4% and 82.1% when cutoff values were set to 1113 (OTU number) or 4.4% RA, respectively (both p < .001). When combining the validated values, the concordance rate was high (91.1%); however, 16S rRNA sequencing had additional positive yield in 9 cases (5.6%) compared with routine diagnostic methods, and much greater additional positive yield compared to histopathology/IHC, culture, RUT, serology separately with 12 (7.4%), 37 (23.0%) and 43 (26.7%).
16S rRNA amplicon sequencing detects potentially important proportion of H. pylori-positive cases that test negative with routine diagnostic methods. The quantitative number of H. pylori can help to understand how it can be changing by diseases and RA give opportunity to understand how H. pylori communicate with other microbiota.
16S rRNA 扩增子测序是一种无需培养即可准确检测微生物感染的方法。目前尚不清楚测序是否比常规诊断方法在幽门螺杆菌检测方面具有额外的优势。
我们招募了患有消化不良的蒙古志愿者。使用常规诊断方法，幽门螺杆菌阳性定义为组织学/免疫组织化学、培养、快速尿素酶试验或血清学阳性；幽门螺杆菌阴性定义为所有这些试验均为阴性。我们对胃活检标本进行 16S rRNA 测序，并使用 ROC 曲线计算操作分类单元（OTU）和相对丰度（RA）的截止值，以定义阳性结果。
我们共检查了 161 名平均年龄为 43.6 岁的个体，其中 64.6%为女性。使用常规诊断方法，122 名（75.8%）参与者幽门螺杆菌阳性，16S rRNA 测序的敏感性和特异性分别为 94.3%和 82.1%，当截止值设定为 1113（OTU 数）或 4.4%RA 时，敏感性和特异性分别为 93.4%和 82.1%（均<0.001）。当结合验证值时，一致性率较高（91.1%）；然而，与常规诊断方法相比，16S rRNA 测序在 9 例（5.6%）中具有额外的阳性结果，与组织学/IHC、培养、RUT、血清学相比，16S rRNA 测序具有更大的额外阳性结果，分别为 12 例（7.4%）、37 例（23.0%）和 43 例（26.7%）。
16S rRNA 扩增子测序检测到常规诊断方法检测为阴性的幽门螺杆菌阳性病例的比例较高。幽门螺杆菌的定量数量可以帮助了解它如何因疾病而变化，而相对丰度则为了解幽门螺杆菌如何与其他微生物群落相互作用提供了机会。
