Greenson J K, Belitsos P C, Yardley J H, Bartlett J G
Johns Hopkins Hospital, Baltimore, Maryland.
Ann Intern Med. 1991 Mar 1;114(5):366-72. doi: 10.7326/0003-4819-114-5-366.
To investigate occult enteric infections and morphologic changes in the small intestine in patients with advanced human immunodeficiency virus (HIV) infection and chronic diarrhea of undefined cause.
Case-control study.
Referral-based clinic and hospital in tertiary care center.
Twenty-two patients with advanced HIV infection (19 with the acquired immunodeficiency syndrome [AIDS], 3 with AIDS-related complex) with chronic diarrhea, selected because of previously negative stool evaluations for bacterial or parasitic pathogens, were compared with 13 patients with advanced HIV infection (9 with AIDS, 4 with AIDS-related complex) without diarrhea by analysis of endoscopic biopsies using light and electron microscopy, viral culture, and morphometric studies. Both groups were convenience samples and had at least 7 months follow-up.
Eleven of twenty-two patients with HIV infection and chronic diarrhea but only 1 of 13 patients without diarrhea showed occult enteric pathogens (that is, undetected by routine studies) after extensive evaluation of duodenal and colorectal biopsies. Mycobacterium avium-intracellulare and microsporidia were the most common occult agents in study patients with diarrhea (5 each). Patients with diarrhea and occult enteric infections had greater weight loss (mean, 14.3 kg compared with 6.2 kg; P less than 0.05) and shorter survival (1 of 11 compared with 8 of 11 still alive; P less than 0.004) than those with diarrhea but no identified pathogens (defined as "AIDS enteropathy"). Duodenal morphometry showed decreased villus-to-crypt ratios because of villus atrophy and crypt elongation in HIV-infected patients both with and without diarrhea compared with normal controls (P less than 0.001 for each). All three groups showed comparable frequencies of epithelial mitoses.
Further endoscopic biopsy evaluation of patients with AIDS who had unexplained chronic diarrhea showed an occult infectious cause in half of the cases. However, altered villus and crypt architecture in advanced HIV infection was independent of the presence of diarrhea or enteric infection and therefore did not correlate with AIDS enteropathy. Subnormal epithelial proliferation in response to injury could be a factor, but the underlying cause of the architectural changes remains obscure. We suggest that T-cell dysfunction may play a role.
调查晚期人类免疫缺陷病毒（HIV）感染且病因不明的慢性腹泻患者的隐匿性肠道感染及小肠形态学变化。
病例对照研究。
三级医疗中心的转诊诊所和医院。
选取22例晚期HIV感染（19例获得性免疫缺陷综合征[AIDS]，3例AIDS相关综合征）伴慢性腹泻的患者，因其之前粪便细菌或寄生虫病原体检测为阴性，与13例晚期HIV感染（9例AIDS，4例AIDS相关综合征）无腹泻的患者进行比较，通过光镜和电镜分析内镜活检、病毒培养及形态计量学研究。两组均为便利样本，且至少随访7个月。
22例HIV感染伴慢性腹泻的患者中有11例，而13例无腹泻的患者中只有1例在对十二指肠和结肠活检进行广泛评估后显示存在隐匿性肠道病原体（即常规检查未检测到）。鸟分枝杆菌复合群和微孢子虫是腹泻患者中最常见的隐匿病原体（各5例）。与腹泻但未发现病原体（定义为“AIDS肠病”）的患者相比，腹泻且有隐匿性肠道感染的患者体重减轻更明显（平均14.3千克对6.2千克；P<0.05），生存期更短（11例中有1例存活对11例中有8例存活；P<0.004）。十二指肠形态计量学显示，与正常对照组相比，无论有无腹泻，HIV感染患者的绒毛与隐窝比值均因绒毛萎缩和隐窝延长而降低（每组P<0.001）。三组上皮有丝分裂频率相当。
对病因不明的慢性腹泻AIDS患者进行进一步内镜活检评估发现，半数病例存在隐匿性感染病因。然而，晚期HIV感染中绒毛和隐窝结构改变与腹泻或肠道感染无关，因此与AIDS肠病不相关。上皮对损伤的增殖反应低于正常水平可能是一个因素，但结构改变的根本原因仍不清楚。我们认为T细胞功能障碍可能起作用。
