West A Brian
Department of Pathology, Yale University, New Haven, CT 06520-8023, USA.
J Clin Gastroenterol. 2008 Nov-Dec;42(10):1137-8. doi: 10.1097/MCG.0b013e3181862a9f.
Diverticulosis of the left colon is an acquired condition that is associated with aging. The diverticula arise at the points of penetration of the circular layer of the muscularis propria by the blood vessels supplying the submucosa and mucosa. They are outpouchings of mucosa invested by wisps of muscularis mucosae, which are believed to result from elevated intraluminal pressure in the left colon, associated with degenerative changes in the collagen and elastin content of the colonic wall. Pathologically, diverticulitis occurs when the mucosa of diverticula becomes inflamed. This may result from obstruction of the diverticulum, for example, by inspissated feces or a fecolith, leading to bacterial overgrowth, gas and toxin production, and mucosal injury. The flat mucosa of the colon between the orifices of the diverticula is also commonly inflamed, with changes of varying severity indistinguishable from those of ulcerative colitis or Crohn's disease. Such mucosal changes include a dense lymphoplasmacytic infiltrate, mucin depletion, cryptitis, crypt abscesses, architectural distortion, gland dropout, Paneth cell metaplasia, and ulceration. Complications of diverticulitis include bleeding (the diverticula are in intimate contact with the penetrating blood vessels which may become eroded), ulceration, abscess formation, penetration, perforation, fistulas, stricture formation, and pylephlebitis.
左半结肠憩室病是一种与衰老相关的后天性疾病。憩室起源于供应黏膜下层和黏膜的血管穿透固有肌层环行层的部位。它们是由黏膜肌层细丝包绕的黏膜膨出，据信是由于左半结肠腔内压力升高，以及结肠壁胶原和弹性蛋白含量的退行性改变所致。病理上，当憩室黏膜发炎时就会发生憩室炎。这可能是由于憩室梗阻引起的，例如被干结粪便或粪石阻塞，导致细菌过度生长、气体和毒素产生以及黏膜损伤。憩室开口之间的结肠扁平黏膜也常发炎，其严重程度各异的变化与溃疡性结肠炎或克罗恩病难以区分。此类黏膜变化包括密集的淋巴浆细胞浸润、黏蛋白减少、隐窝炎、隐窝脓肿、结构扭曲、腺体缺失、潘氏细胞化生和溃疡形成。憩室炎的并发症包括出血（憩室与穿透性血管紧密接触，血管可能被侵蚀）、溃疡形成、脓肿形成、穿透、穿孔、瘘管形成、狭窄形成和门静脉炎。
