How does coronavirus kill? -9

感染肠道1

3月初，一名71岁的密歇根州妇女因流血性腹泻，呕吐和腹痛从尼罗河游船返回。起初，医生怀疑她就是得了一种比较常见的胃病，例如沙门氏菌感染。但在她出现咳嗽症状后，医生用鼻腔拭子检测到了她是被新型冠状病毒感染了。根据《美国胃肠病学杂志》(AJG)在线发表的一篇论文显示：如果粪便样本的病毒RNA检测呈阳性，以及内窥镜检查中发现结肠损伤迹象，就表明冠状病毒感染了胃肠道(GI)。

有证据表明，这种新型冠状病毒就像它的“近期”SARS一样，可以感染下消化道的内壁，那里有大量至关重要的ACE2受体，这个病例进一步支持了这一论断。在多达53%的患者粪便样本中发现了病毒RNA。在《胃肠病学》(Gastroenterology)杂志上发表的一篇论文中，一个中国团队报告说在一名COVID-19患者的活检组织中发现了该病毒在胃，十二指肠和直肠细胞中的蛋白质外壳。贝勒医学院的病毒学家Mary Estes说:“我认为它可能确实会在胃肠道中复制。”

AJG联合主编洛杉矶的Cedars-Sinai医学中心的Brennan Spiegel说，最近的报告表明多达一半的患者（平均在整个研究中大约有20％）会经历腹泻。 Spiegel等人说，GI症状不在CDC的COVID-19症状列表中，这可能导致某些COVID-19病例没有被检测到。“如果你的主要症状是发烧和腹泻，你就不会进行COVID检查”北加州凯撒医疗机构的道格拉斯·科利如是说，他是《胃肠病学》的共同编辑。

Reaching the gut-1

In early March, a 71-year-old Michigan woman returned from a Nile River cruise with bloody diarrhea, vomiting, and abdominal pain. Initially doctors suspected she had a common stomach bug, such as Salmonella. But after she developed a cough, doctors took a nasal swab and found her positive for the novel coronavirus. A stool sample positive for viral RNA, as well as signs of colon injury seen in an endoscopy, pointed to a gastrointestinal (GI) infection with the coronavirus, according to a paper posted online in The American Journal of Gastroenterology (AJG).

Her case adds to a growing body of evidence suggesting the new coronavirus, like its cousin SARS, can infect the lining of the lower digestive tract, where the crucial ACE2 receptors are abundant. Viral RNA has been found in as many as 53% of sampled patients’ stool samples. And in a paper in press at Gastroenterology, a Chinese team reported finding the virus’ protein shell in gastric, duodenal, and rectal cells in biopsies from a COVID-19 patient. “I think it probably does replicate in the gastrointestinal tract,” says Mary Estes, a virologist at Baylor College of Medicine.

Recent reports suggest up to half of patients, averaging about 20% across studies, experience diarrhea, says Brennan Spiegel of Cedars-Sinai Medical Center in Los Angeles, co–editor-in-chief of AJG. GI symptoms aren’t on CDC’s list of COVID-19 symptoms, which could cause some COVID-19 cases to go undetected, Spiegel and others say. “If you mainly have fever and diarrhea, you won’t be tested for COVID,” says Douglas Corley of Kaiser Permanente, Northern California, co-editor of Gastroenterology.

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