Background & Aims

Lymphocytic and collagenous colitis are types of microscopic colitis (MC) that commonly cause chronic watery diarrhea, but there are no macroscopic features of MC that can be detected during colonoscopy. Endoscopists therefore often collect multiple random colonic biopsies, potentially oversampling, increasing times of colonoscopy and slide review. We sought to identify sites from which biopsies could be taken and analyzed to identify patients with MC with a high level of sensitivity and determine the appropriate number of biopsies to take at these sites.

Methods

We performed a retrospective study using biopsies from 101 consecutive patients with MC (52 cases of collagenous colitis, 42 cases of lymphocytic colitis, 7 combined cases), without comorbidities, from 2017 through 2018. Slides were reviewed, and the proportion of biopsies that were diagnostic of MC were calculated at each biopsy site.

Results

The proportions of biopsy fragments from each site of the colon found to be positive for MC were as follows: cecum, 90.0%; ascending colon, 96.9%; hepatic flexure, 77.8%; transverse colon, 95.7%; splenic flexure, 75.0%; descending colon, 85.0%; sigmoid colon, 90.9%; and rectum, 82.2%. For biopsies labeled random, 95.7% were positive for MC. When findings from ascending and descending colon biopsies were combined, 100% of MC cases were detected.

Conclusions

MC can be detected with certainty by analyzing biopsies from the ascending and descending colon. Fewer biopsies than were collected from our cases are sufficient for diagnosis. We propose a Western protocol (taking 2 biopsies from each of the ascending and descending colon) in evaluation of patients for MC.

中文翻译：

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升结肠和降结肠的活检足以诊断显微结肠炎。

背景与目标

淋巴细胞性结肠炎和胶原性结肠炎是显微镜下结肠炎 (MC) 的类型，通常会导致慢性水样泻，但在结肠镜检查中无法检测到 MC 的宏观特征。因此，内窥镜医师通常会随机收集多个结肠活检，这可能会导致采样过多，从而增加结肠镜检查和切片检查的次数。我们试图确定可以进行活检的部位，并进行分析以识别具有高度敏感性的 MC 患者，并确定在这些部位进行活检的适当数量。

方法

我们使用 2017 年至 2018 年 101 名无合并症的连续 MC 患者（52 例胶原性结肠炎、42 例淋巴细胞性结肠炎、7 例合并症）的活检进行了一项回顾性研究。在每个活检部位计算 MC 的诊断。

结果

发现 MC 阳性的结肠每个部位的活检碎片比例如下：盲肠，90.0%；升结肠，96.9%；肝曲，77.8%；横结肠，95.7%；脾曲，75.0%；降结肠，85.0%；乙状结肠，90.9%；和直肠，82.2%。对于标记为随机的活检，95.7% 为 MC 阳性。当升结肠和降结肠活检的结果相结合时，100% 的 MC 病例被检测到。

结论

通过分析升结肠和降结肠的活检，可以肯定地检测到 MC。比从我们的病例中收集的活检数量少，足以进行诊断。我们提出了一种西方方案（从每个升结肠和降结肠取 2 个活组织检查）来评估 MC 患者。