特应性皮炎患儿与正常儿童肠道菌群差异性研究

【摘要】 目的 探讨特应性皮炎（AD） 患儿与正常儿童肠道菌群的差异。方法 收集2015年4月至2017年4月在上海市嘉定区中医医院皮肤科门诊就诊的AD患儿35例,以27例健康儿童作为对照组。取受试者粪便,提取总DNA后,PCR扩增细菌的16SrRNA基因V3 ~ V4区,应用Illumina Miseq测序平台行高通量测序,分析菌群丰度差异。选择两组丰度排名前15的门、属、种分别比较物种差异,采用Wilcoxon秩和检验。结果 两组肠道菌群主要由厚壁菌门、拟杆菌门、变形菌门、放线菌门组成。在菌门水平,AD组与健康对照组拟杆菌门丰度分别为29.16% ± 19.96%、39.06% ± 15.98%（P = 0.042）,梭杆菌门分别为0.06% ± 0.17%、0.50% ± 1.71%（P = 0.041）;在菌属水平,两组拟杆菌属丰度分别为23.77% ± 18.08%、33.1% ± 15.75%（P = 0.029）;在菌种水平,丰度排名前15的菌种两组间分布差异均无统计学意义（均P > 0.05）。结论 特应性皮炎患儿与正常儿童肠道菌群构成及菌群相对丰度存在一定差异。     

Mucosal Invasion by Fusobacteria is a Common Feature of Acute Appendicitis in Germany, Russia, and China

Background/Aim:

To investigate the geographic occurrence of mucosa-invading Fusobacteria in acute appendicitis.

Patients and Methods:

Carnoy- and formalin-fixated appendices from Germany, Russia, and China were comparatively investigated. Bacteria were detected using fluorescent in situ hybridization. Cecal biopsies from patients with inflammatory bowel disease and other conditions were used as disease controls.

Results:

Fusobacteria represented mainly by Fusobacterium nucleatum were the major invasive component in bacterial infiltrates in acute appendicitis but were completely absent in controls. The occurrence of invasive Fusobacteria in Germany, Russia, and China was the same. The detection rate in Carnoy-fixated material was 70–71% and in formalin-fixated material was 30–36%.

Conclusions:

Acute appendicitis is a polymicrobial infectious disease in which F. nucleatum and other Fusobacteria play a key role.     

Demonstration of fusobacteria in eruptions of perioral dermatitis using the tape stripping toluidine blue (TSTB) method

Background and design To dale the pathogenesis of perioral dermatitis has not been completely-understood. The role of fusobacteria was postulated by some investigators during the 1970s and subsequently disputed by others, who failed to confirm the presence of these bacteria. In a 6-year period we investigated 341 patients with various facial eruptions, using the tape stripping toluidine blue (TSTB) method. According 1.0 the first clinical diagnosis 70 patients presented perioral dermatitis and 271 other facial conditions, including seborrheic dermatitis, rosacea, acne, contact dermatitis and bacterial infections. Results Fusobacteria were found in 57 (81%) of the 70 patients with perioral dermatitis, and in 14 (5%) of the 271 with other conditions. When only the clinically typical, unquestionable cases were considered, the percentages were 95% and 0%, respectively. Conclusions Our data support the view that fusobacteria are possibly involved in the pathogenesis of perioral dermatitis.     

Fusobacterium nucleatum

The Gram-negative, non-sporulating, obligately anaerobic species, Fusobacterium nucleatum, is rapidly gaining notoriety as a pathogen with a surprising number of associated diseases. Recently, we have found that F. nucleatum is a more common resident of the GI tract than originally thought, and thus, through several studies, we have attempted to determine its gut-relevant potential for virulence. We have found that F. nucleatum possesses a number of pathogenic traits with relevance to gut diseases such as inflammatory bowel disease (IBD), however, we have also documented strain-associated differences in virulence. An intriguing picture emerges that paints F. nucleatum as both conferring beneficial as well as detrimental effects on host cells; and we suggest that the ultimate effects of F. nucleatum infection in the gut are a consequence of the microbes with which this species aggregates.     

Acute appendicitis in children is associated with an abundance of bacteria from the phylum Fusobacteria

Background

Although luminal obstruction has traditionally been viewed as the underlying cause of appendicitis, recent evidence has suggested that the disease may result directly from invasion by specific pathogens, e.g. Fusobacterium nucleatum. The purpose of this study was to survey microbial communities within pediatric appendectomy specimens using a culture-independent approach.

Methods

We performed 16S ribosomal gene sequence analysis to profile the microbiota present within luminal fluid obtained from 22 pediatric appendectomy specimens. These included 10 simple appendicitis cases, 5 perforated appendicitis cases, 2 interval appendectomies, and 5 incidental appendectomies.

Results

Samples could be divided into 2 distinct clusters based upon the composition of the appendiceal bacterial communities. Appendicitis samples contained an increased abundance of Fusobacterium spp. and a reduced abundance of Bacteroides spp. relative to non-appendicitis cases. Appendicitis samples also contained variable amounts of other oral taxa such as Porphyromonas, Parvimonas, and Gemella, whereas these taxa were generally absent from non-appendicitis samples.

Conclusions

Acute appendicitis is associated with an abundance of Fusobacterium spp. and other pathogens commonly found in the oral cavity. Further research is needed to determine whether these organisms directly cause appendicitis or rather proliferate in the appendix as a secondary consequence of inflammation.