Medically Associated Science and Technology (MAST) Program, Cedars-Sinai Medical Center, Los Angeles, California, USA.
Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, California, USA.
BMJ Open Gastroenterol. 2020 Jun;7(1). doi: 10.1136/bmjgast-2020-000412.
To compare the appendiceal microbiomes and examine the prevalence of species in the appendices of adult subjects with confirmed acute non-perforated appendicitis and controls with healthy appendices.
Archived samples of formalin-fixed paraffin-embedded appendiceal tissues were obtained from 50 consecutive female subjects who underwent appendectomy for acute, non-perforated appendicitis, and 35 consecutive female controls who underwent incidental appendectomy during gynaecological surgery.
16S rRNA gene sequencing revealed that the relative abundances (RAs) of the major phyla in appendiceal tissues (Firmicutes, Proteobacteria, Bacteroidetes, and Actinobacteria) were similar in both groups. Beta diversity was significantly different due to differences in Bacteroidetes and Proteobacteria (p<0.0001). Within Proteobacteria, RAs of classes Alphaproteobacteria (21%, fold change (FC)=1.31, false discovery rate (FDR) p value=0.03) and Epsilonproteobacteria (1%, FC=0.25, FDR p value>0.05) were increased in acute appendicitis samples. RAs of unknown genera from families Burkholderiaceae and Enterobacteriaceae were decreased in appendicitis samples, and 14 genera were increased, including , and . Quantitative PCR revealed that levels of DNA, but not other species or pathogens tested, were significantly higher in appendicitis samples than in controls (p=0.013). Using a cut-off of 0.31 pg/µL, 40% of appendicitis cases and 6% of controls were positive for , indicating specificity of 93.7% (95% Cl 79.2 to 99.2), sensitivity of 40.9% (95% Cl 24.7 to 54.5), and OR of 10.38 (Fisher's p value=0.0006, 95% Cl 2.3 to 47.4).
Our findings indicate that may be a significant cause of acute appendicitis. This supports earlier studies and suggests that targeted antibiotic therapies could be an alternative treatment for a subset of non-complicated acute appendicitis cases.
比较阑尾微生物组，并检查在经证实患有急性非穿孔性阑尾炎的成年患者和患有健康阑尾的对照者的阑尾中 种的流行情况。
从 50 名连续接受因急性非穿孔性阑尾炎而行阑尾切除术的女性患者和 35 名连续接受妇科手术时偶然行阑尾切除术的女性对照者的福尔马林固定石蜡包埋阑尾组织的存档样本中获得 16S rRNA 基因测序。
阑尾组织中主要菌群（厚壁菌门、变形菌门、拟杆菌门和放线菌门）的相对丰度（RA）在两组间相似。由于拟杆菌门和变形菌门的差异，β多样性差异显著（p<0.0001）。在变形菌门中，α变形菌纲（21%，倍数变化（FC）=1.31，错误发现率（FDR）p 值=0.03）和γ变形菌纲（1%，FC=0.25，FDR p 值>0.05）的 RA 在急性阑尾炎样本中增加。在阑尾炎样本中，来自伯克霍尔德氏菌科和肠杆菌科的未知属的 RA 减少，有 14 个属增加，包括 、 和 。定量 PCR 显示，在阑尾炎样本中， DNA 水平而非其他测试的 种或病原体水平显著高于对照组（p=0.013）。使用 0.31 pg/µL 的截断值，40%的阑尾炎病例和 6%的对照组对 呈阳性，表明 93.7%（95%Cl 79.2 至 99.2）的特异性、40.9%（95%Cl 24.7 至 54.5）的敏感性和 10.38 的 OR（Fisher 检验 p 值=0.0006，95%Cl 2.3 至 47.4）。
我们的研究结果表明， 可能是急性阑尾炎的一个重要原因。这支持了早期的研究，并表明针对特定的抗生素治疗可能是一种非复杂性急性阑尾炎病例的替代治疗方法。
