Analysis of fecal microbiota and related clinical indicators in ICU patients with sepsis.

Background: To analyze the characteristics of fecal microbiota disturbance in the intensive care unit (ICU) patients with sepsis and the correlation with related clinical indicators. Methods: This study included 31 patients with sepsis admitted to the emergency ICU ward between September 2019 and December 2021. They were divided into Group without septic shock (ND_NS group, 7 cases) and Group with septic shock (ND_S group, 24 cases) according to the presence or absence of septic shock. Furthermore, we divided these 31 sepsis patients into Clinical Improvement group (21 cases) and Death or DAMA group (10 cases) based on clinical outcome, 15 cases of Physical Examiner recruited in the same period were included as control group: ND_HC group (15 cases). The fecal samples of the patients with sepsis within 24 h of admission and random fecal samples of the control group were collected and analyzed by 16S rDNA gene sequencing used for the analysis of fecal microbiota. At the same time, the relevant clinical data of these patients with sepsis were also collected for analysis. Results: There were 15 cases with drug-resistant bacteria in the ND_S group and only 2 cases in the ND_NS group (P = 0.015). There were significant differences in APACHE II score, length of ICU stay, lactate level, and oxygenation index of patients between the Death or DAMA group and Clinical Improvement group (all P < 0.05). For phylum level, the abundance of Firmicutes, Actinobacteria, and Bacteroidetes decreased in the ND group compared with the ND_HC group, while the abundance of Proteobacteria increased (P < 0.05). For genus level, the relative abundance of Escherichia-Shigella and Klebsiella were significantly increased in the ND group compared with the ND_HC group (P < 0.05). The top six genera in relative abundance in the ND_S group were Escherichia-Shigella, Enterococcus, Bifidobacterium, Lactobacillus, Akkermansia, and Klebsiella. Compared with the Clinical Improvement group, the relative abundance of Escherichia-Shigella and Klebsiella in the Death or DAMA group showed an increasing trend with no significant significance, while the relative abundance of Enterococcus and Faecalibacterium decreased in the Death or DAMA group (P < 0.05). Alpha diversity analysis showed that compared with the ND_HC group, the alpha diversity of the fecal microbiota in the ND group decreased. There were significant differences in the Observed_species index, Chao1 index, and ACE index of patients between the ND_HC group and ND group (all P < 0.05). Moreover, compared with the ND_NS group, the Alpha diversity of the ND_S group was more abundant. PCoA analysis showed significant differences in microbial community structure between the ND group and ND_HC group (P = 0.001). There also were significant differences in microbial community structure between the ND_S group and ND_NS group (P = 0.008). LEfSe analysis showed that compared with the ND_HC group, there were significant differences in the species of the ND group, including Enterobacteriaceae, Escherichia-Shigella, Enterococcus, Elizabethkingia, and Family_XIII_AD3011_group. Conclusions: ICU patients with sepsis suffered intestinal microecological disturbances with significantly decreased abundance of fecal microbiota, diversity, and beneficial symbiotic bacteria. For these patients, the ratio of pathogenic bacteria, including Escherichia-Shigella and Klebsiella increased and became the main bacterial genus in some samples. Moreover, the increasing trend of these two pathogenic bacteria may be correlated with the development of septic shock and the risk of death in patients with sepsis.

Appendectomy Is Associated With Alteration of Human Gut Bacterial and Fungal Communities.

Recent research has revealed the importance of the appendix in regulating the intestinal microbiota and mucosal immunity. However, the changes that occur in human gut microbial communities after appendectomy have never been analyzed. We assessed the alterations in gut bacterial and fungal populations associated with a history of appendectomy. In this cross-sectional study, we investigated the association between appendectomy and the gut microbiome using 16S and ITS2 sequencing on fecal samples from 30 healthy individuals with prior appendectomy (HwA) and 30 healthy individuals without appendectomy (HwoA). Analysis showed that the gut bacterial composition of samples from HwA was less diverse than that of samples from HwoA and had a lower abundance of Roseburia, Barnesiella, Butyricicoccus, Odoribacter, and Butyricimonas species, most of which were short-chain fatty acids-producing microbes. The HwA subgroup analysis indicated a trend toward restoration of the HwoA bacterial microbiome over time after appendectomy. HwA had higher gut fungi composition and diversity than HwoA, even 5 years after appendectomy. Compared with those in samples from HwoA, the abundance correlation networks in samples from HwA displayed more complex fungal-fungal and fungal-bacterial community interactions. This study revealed a marked impact of appendectomy on gut bacteria and fungi, which was particularly durable for fungi.

BPTES inhibits anthrax lethal toxin-induced inflammatory response.

Bacillus anthracis is a lethal agent of anthrax disease and the toxins are required in anthrax pathogenesis. The anthrax lethal toxin can trigger NLRP1b inflammasome activation and pyroptosis. Although the underlying mechanism is well understood, the medications targeting the NLRP1b inflammasome are not available in the clinic. Herein, we describe that BPTES, a known Glutaminase (GLS) inhibitor, is an effective NLRP1b inflammasome inhibitor. BPTES could effectively and specifically suppress NLRP1b inflammasome activation in macrophages but have no effects on NLRP3, NLRC4 and AIM2 inflammasome activation. Mechanistically, BPTES alleviated the UBR2 mediated proteasomal degradation pathway of the NLRP1b N terminus, thus blocking the release of the CARD domain for subsequent caspase-1 processing. Furthermore, BPTES could prevent disease progression in mice challenged with the anthrax lethal toxin. Taken together, our studies indicate that BPTES can be a promising pharmacological inhibitor to treat anthrax lethal toxin-related inflammatory diseases.

Synergistic effect of enteral nutrition on remission induction in a patient with penetrating Crohn disease: A case report.

RATIONALE: Crohn disease includes 3 phenotypes, inflammatory, stricturing, and penetrating. In cases where corticosteroids and immunosuppressive agents are not suitable treatment options, enteral nutrition (EN) can be used to reduce disease severity and enhance barrier defense with fewer potential adverse effects. PATIENT CONCERNS: A 23-year-old man with abdominal pain and diarrhea presented at our hospital in 2014. The frequency of defecation was 3 or 4 times a day without mucus or blood in the stool. His body mass index was 15.8, and in laboratory tests the erythrocyte sedimentation rate was 42.4 mm/h, serum C reactive protein was 65.2 mg/L, the leukocyte count was 11.64 × 109/L, and hemoglobin was 111 g/L. DIAGNOSIS: In computed tomography (CT) enterography the ascending colon was thickened, and there was effusion and enlarged lymph nodes around the colon. Colonoscopy revealed ulcer, polypoid proliferation, and bowel stenosis in many segments. Chronic inflammation was evident in multiple biopsies. Crohn disease was diagnosed based on the above observations. INTERVENTIONS: Mesalazine was administered at a dose of 4 g daily for 2 years. The patient was hospitalized again due to severe abdominal pain and ongoing fever. Intestinal perforation was detected via CT. Percutaneous drainage was performed followed by administration of intravenous metronidazole (0.5 g) and ciprofloxacin (0.2 g) twice a day. Peptison liquid was used as exclusive EN. After 2 weeks the antibiotics regimen was changed to metronidazole 0.4 g twice a day and ciprofloxacin 0.25 g 3 times a day, both administered orally. OUTCOMES: CT revealed that the infection was eliminated and the fistula was healed after 10 weeks, at which point antibiotics and exclusive EN was discontinued. Azathioprine was prescribed at a dose of 2 mg/kg daily to maintain clinical remission. The patient did not report any pain or diarrhea at a 1-year follow-up visit. LESSONS: The present case suggests that exclusive EN combined with antibiotics is useful in inducing remission in Crohn disease patients with active disease and penetrating complications.