Department of Gastroenterology and Hepatology, University Hospital Zurich, Zurich, Switzerland; Zentrum für Gastroenterologie und Hepatologie, Zurich, Switzerland.
Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland; Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
Clin Gastroenterol Hepatol. 2020 Sep;18(10):2218-2225.e2. doi: 10.1016/j.cgh.2019.11.036. Epub 2019 Nov 25.
BACKGROUND & AIMS: It is not clear how rapid ascent to a high altitude causes the gastrointestinal symptoms of acute mountain sickness (AMS). We assessed the incidence of endoscopic lesions in the upper gastrointestinal tract in healthy mountaineers after a rapid ascent to high altitude, their association with symptoms, and their pathogenic mechanisms.
In a prospective study, 25 mountaineers (10 women; mean age, 43.8 ± 9.5 y) underwent unsedated, transnasal esophagogastroduodenoscopy in Zurich (490 m) and then on 2 test days (days 2 and 4) at a high altitude laboratory in the Alps (Capanna Regina Margherita, 4559 m). Symptoms were assessed using validated instruments for AMS (the acute mountain sickness score and the Lake Louise scoring system) and visual analogue scales (scale, 0-100). Levels of messenger RNAs (mRNAs) in duodenal biopsy specimens were measured by quantitative polymerase chain rection.
The follow-up endoscopy at high altitude was performed in 19 of 25 patients on day 2 and in 23 of 25 patients on day 4. The frequency of endoscopic lesions increased from 12% at baseline to 26.3% on day 2 and to 60.9% on day 4 (P < .001). The incidence of ulcer disease increased from 0 at baseline to 10.5% on day 2 and to 21.7% on day 4 (P = .014). Mucosal lesions were associated with lower hunger scores (37.3 vs 67.4 in patients without lesions; P = .012). Subjects with peptic lesions had higher levels of HIF2A mRNA, which encodes a hypoxia-induced transcription factor, and ICAM1 mRNA, which encodes an adhesion molecule, compared with subjects without lesions (fold changes, 1.38 vs 0.63; P = .001; and 1.37 vs 0.66; P = .011, respectively).
In a prospective study of 25 mountaineers, fast ascent to a high altitude resulted in rapid onset of clinically meaningful mucosal lesions and ulcer disease. Duodenal biopsy specimens from these subjects had increased levels of HIF2A mRNA and ICAM1 mRNA, which might contribute to the formation of hypoxia-induced peptic lesions. Further studies are needed of the mechanisms of this process.
目前尚不清楚快速上升到高海拔如何引起急性高原病（AMS）的胃肠道症状。我们评估了健康登山者快速上升到高海拔后上消化道内镜下病变的发生率，以及这些病变与症状的关系和发病机制。
在一项前瞻性研究中，25 名登山者（10 名女性；平均年龄 43.8±9.5 岁）在苏黎世（海拔 490 米）进行了未经镇静的经鼻食管胃十二指肠镜检查，然后在阿尔卑斯山的一个高海拔实验室（卡彭纳雷吉纳玛格丽塔，海拔 4559 米）在 2 个测试日（第 2 天和第 4 天）进行检查。使用经过验证的 AMS （急性高原病评分和路易斯湖评分系统）和视觉模拟量表（量表，0-100）评估症状。通过定量聚合酶链反应测量十二指肠活检标本中的信使 RNA（mRNA）水平。
25 名患者中有 19 名在第 2 天和 23 名在第 4 天进行了高海拔的随访内镜检查。内镜下病变的频率从基线时的 12%增加到第 2 天的 26.3%和第 4 天的 60.9%（P<.001）。溃疡病的发生率从基线时的 0%增加到第 2 天的 10.5%和第 4 天的 21.7%（P=.014）。黏膜病变与饥饿评分较低相关（有病变者为 37.3，无病变者为 67.4；P=.012）。与无病变者相比，有消化性病变者的 HIF2A mRNA 和 ICAM1 mRNA 水平升高，HIF2A mRNA 编码缺氧诱导的转录因子，ICAM1 mRNA 编码黏附分子（倍数变化，1.38 比 0.63；P=.001；1.37 比 0.66；P=.011）。
在 25 名登山者的前瞻性研究中，快速上升到高海拔导致了有临床意义的黏膜病变和溃疡病的快速发生。来自这些受试者的十二指肠活检标本中 HIF2A mRNA 和 ICAM1 mRNA 水平升高，这可能有助于形成缺氧诱导的消化性病变。需要进一步研究该过程的机制。
