The normal water content value in stools is approximately 10 mL/kg/day in infants and young children or 200 g/day in teenagers and adults. Diarrhea is the augmentation of water content in stools because of an imbalance in the normal functioning of physiologic processes of the small and large intestine responsible for the absorption of various ions, other substrates, and, consequently, water. Acute diarrhea is the onset of 3 or more loose or watery stools a day lasting 14 days or less. However, chronic or persistent diarrhea is labeled when an episode lasts beyond 14 days. Infection commonly causes acute diarrhea. Noninfectious etiologies become more common as the duration of diarrhea becomes chronic. This distinction is important because treatment and management are based on the duration and specific etiology. Rehydration therapy is an important aspect of managing any patient with diarrhea. Prevention of infectious diarrhea includes proper handwashing to prevent the spread of infection. The term "acute gastroenteritis" is synonymously used with "acute diarrhea"; however, the former is a misnomer. The term gastroenteritis signifies both gastric and small intestinal involvement, whereas, practically, it is rarely seen in acute diarrhea, even if it is the infective form of diarrhea. Additionally, enteritis is also not always present. Examples of infectious diarrhea without enteritis include cholera and shigellosis. Hence, using the term acute diarrhea instead of acute gastroenteritis is more clinically appropriate.
婴幼儿粪便中的正常含水量约为10毫升/千克/天,青少年和成年人则为200克/天。腹泻是指由于负责吸收各种离子、其他底物以及随之而来的水分的小肠和大肠生理过程正常功能失衡,导致粪便含水量增加。急性腹泻是指每天出现3次或更多次稀便或水样便,持续时间不超过14天。然而,如果腹泻持续超过14天,则称为慢性或持续性腹泻。感染通常会导致急性腹泻。随着腹泻持续时间延长,非感染性病因更为常见。这种区分很重要,因为治疗和管理是基于腹泻持续时间和具体病因。补液疗法是治疗任何腹泻患者的重要方面。预防感染性腹泻包括正确洗手以防止感染传播。术语“急性肠胃炎”与“急性腹泻”同义使用;然而,前者是一个误称。肠胃炎一词意味着胃和小肠都受累,而实际上,即使在感染性腹泻中,急性腹泻也很少出现这种情况,肠炎也并非总是存在。没有肠炎的感染性腹泻的例子包括霍乱和志贺氏菌病。因此,使用急性腹泻这个术语而不是急性肠胃炎在临床上更合适。