Gut microbiota in neonates with congenital gastrointestinal surgical conditions: a prospective study

Impact of intestinal colonization by Gram-negative bacteria on the incidence of bloodstream infections and lethality in critically ill neonates

BACKGROUND

Early detection of antimicrobial-resistant microorganisms is crucial to prevent subsequent invasive infections and contain their spread in the Neonatal Intensive Care Unit (NICU). This study aims to investigate the association between intestinal colonization (IC) by Gram-negative bacteria and the risk of bloodstream infection (BSI) in critically ill neonates.

METHODS

Data from the electronic medical records of 678 newborns admitted to a NICU Brazilian between 2018 and 2022 were retrospectively analyzed. Participants were monitored by the National Health Security Network.

RESULTS

Among neonates, 6.9 % had IC (56.9 % attributed to Acinetobacter baumannii); of these, 19.1 % developed BSI (66.7 % by Staphylococcus spp.). Within the A. baumannii colonization, 34.5 % occurred during an outbreak in September 2021. Colonized individuals had a longer mean length of stay (49.3 ± 26.4 days) and higher mortality rate (12.8 %) compared to non-colonized individuals (22.2 ± 16.9 days; 6.7 %, respectively). Previous use of antimicrobials and invasive devices significantly increased the risk of colonization. Colonization by drug-resistant microorganisms, along with the occurrence of BSI, was associated with increased mortality and reduced survival time.

CONCLUSIONS

IC contributed to the incidence of BSI, leading to more extended hospital stays and higher mortality rates. Its early detection proved to be essential to identify an outbreak and control the spread of resistant microorganisms within the NICU.

Araújo J, Marques C, Sousa L, Morais J, Castela I, Faria A, Neto MT, Cordeiro-Ferreira G, Virella D, Pita A, Pereira-da-Silva L, Calhau C. Changes in Microbiota Profile in the Proximal Remnant Intestine in Infants Undergoing Surgery Requiring Enterostomy

Early-life gut dysbiosis has been associated with an increased risk of inflammatory, metabolic, and immune diseases later in life. Data on gut microbiota changes in infants undergoing intestinal surgery requiring enterostomy are scarce. This prospective cohort study examined the enterostomy effluent of 29 infants who underwent intestinal surgery due to congenital malformations of the gastrointestinal tract, necrotizing enterocolitis, or spontaneous intestinal perforation. Initial effluent samples were collected immediately after surgery and final effluent samples were collected three weeks later. Gut microbiota composition was analysed using real-time PCR and 16S rRNA gene sequencing. Three weeks after surgery, an increase in total bacteria number (+21%, p = 0.026), a decrease in Staphylococcus (-21%, p = 0.002) and Candida spp. (-16%, p = 0.045), and an increase in Lactobacillus (+3%, p = 0.045) and in less abundant genera belonging to the Enterobacteriales family were found. An increase in alpha diversity (Shannon's and Simpson's indexes) and significant alterations in beta diversity were observed. A correlation of necrotizing enterocolitis with higher Staphylococcus abundance and higher alpha diversity was also observed. H2-blockers and/or proton pump inhibitor therapy were positively correlated with a higher total bacteria number. In conclusion, these results suggest that positive changes occur in the gut microbiota profile of infants three weeks after intestinal surgery.

Perioperative and Long-Term Outcome in Patients Treated for Jejunoileal Atresia

OBJECTIVES

Jejunoileal atresia is a common cause of neonatal intestinal obstruction. Results of long-term outcome are very limited. The aim of this study was to describe perioperative and postoperative outcome, and to evaluate long-term gastrointestinal quality of life (QoL) in patients treated for jejunoileal atresia.

METHODS

We conducted a combined retrospective and cross-sectional observational study of patients treated for jejunoileal atresia during 2001-2019. Perioperative data were registered, and complications were classified according to the Clavien-Dindo classification. To evaluate long-term clinical status and QoL, the PedsQL Gastrointestinal Symptoms Scales questionnaire and a self-designed questionnaire were used. Approval from the Data Protection Office was obtained.

RESULTS

Seventy patients were included in the retrospective part of the study. Of these, 70% got a primary anastomosis. Concomitant anomalies were registered in 46%. Median length of stay was 28 (5-140) days. Early (<28 days) complication rate was 66%. Early abdominal surgical reinterventions were performed in 11%, most frequently due to anastomotic leak. Late (>28 days) abdominal surgical reinterventions were performed in 21%, and most commonly for bowel obstruction. Overall mortality rate was 4%. Thirty-two patients with median 8 (2-19) years returned the questionnaires. Overall gastrointestinal QoL was good. However, concomitant gastrointestinal anomalies were associated with impaired outcome. Embarrassment of the scar was reported in 38%. Three (9%) patients used medication (laxatives, proton pump inhibitor) for gastrointestinal symptoms.

CONCLUSIONS

Jejunoileal atresia is associated with significant morbidity during initial treatment. Despite this, the majority of the patients have excellent long-term outcomes.

Probiotic supplementation for neonates with congenital gastrointestinal surgical conditions: guidelines for future research

Our pilot RCT found that probiotic supplementation with the three-strain bifidobacterial product (B. breve M-16V, B. longum subsp. infantis M-63 and B. longum subsp. longum BB536) attenuates gut dysbiosis, increases stool short-chain fatty acid (SCFA) levels and improves the growth of head circumference in neonates with congenital gastrointestinal surgical conditions (CGISC). In this article, we have provided guidelines for designing future multicentre RCTs based on the experience gained from our pilot RCT. The recommendations include advice about sample size, potential confounders, outcomes of interest, probiotic strain selection, storage, dose, duration and microbial quality assurance, collection of stool samples, storage and analysis and reporting. Following these guidelines will increase the validity of future RCTs in this area and hence confidence in their results. IMPACT: Probiotic supplementation attenuates gut dysbiosis, increases stool short-chain fatty acid (SCFA) levels and improves the growth of head circumference in neonates with congenital gastrointestinal surgical conditions. The current review provides evidence-based guidelines to conduct adequately powered RCTs in this field.

Honeys with anti-inflammatory capacity can alter the elderly gut microbiota in an ex vivo gut model

The anti-inflammatory effect of different sourced honeys and the impact on elderly gut microbiota were studied in terms of chemical compositions, anti-inflammatory effect and gut microbiota modulating capacities. All four honeys suppressed the production of pro-inflammatory markers NO, IL-1β and IL-6 induced by lipopolysaccharide and promoted the expression of anti-inflammatory cytokines IL-10 in RAW 264.7 cells. Moreover, in the ex vivo batch gut model using elderly fecal microbiota (referred to as microcosm), it was showed that the addition of honeys increased the abundance of beneficial lactobacilli, decreased the abundance of potentially harmful Gram negative enteric bacteria, and exerted a beneficial effect on the production of short chain fatty acids. The concentration of gallic acid in honeys was positively correlated with the expression level of IL-10 and the abundance of lactobacilli. These findings indicate honeys with anti-inflammatory capacity have great potential for regulating the elderly gut microbiota which would lead to health benefits.

Breastfeeding Affects Concentration of Faecal Short Chain Fatty Acids During the First Year of Life: Results of the Systematic Review and Meta-Analysis

Short chain fatty acids (SCFAs) are important metabolites of the gut microbiota. It has been shown that the microbiota and its metabolic activity in children are highly influenced by the type of diet and age. Our aim was to analyse the concentration of fecal SCFAs over two years of life and to evaluate the influence of feeding method on the content of these compounds in feces. We searched PubMed/MEDLINE/Embase/Ebsco/Cinahl/Web of Science from the database inception to 02/23/2021 without language restriction for observational studies that included an analysis of the concentration of fecal SCFAs in healthy children up to 3 years of age. The primary outcome measures-mean concentrations-were calculated. We performed a random-effects meta-analysis of outcomes for which ≥2 studies provided data. A subgroup analysis was related to the type of feeding (breast milk vs. formula vs. mixed feeding) and the time of analysis (time after birth). The initial search yielded 536 hits. We reviewed 79 full-text articles and finally included 41 studies (n = 2,457 SCFA analyses) in the meta-analysis. We found that concentrations of propionate and butyrate differed significantly in breastfed infants with respect to time after birth. In infants artificially fed up to 1 month of age, the concentration of propionic acid, butyric acid, and all other SCFAs is higher, and acetic acid is lower. At 1–3 months of age, a higher concentration of only propionic acid was observed. At the age of 3–6 months, artificial feeding leads to a higher concentration of butyric acid and the sum of SCFAs. We concluded that the type of feeding influences the content of SCFAs in feces in the first months of life. However, there is a need for long-term evaluation of the impact of the observed differences on health later in life and for standardization of analytical methods and procedures for the study of SCFAs in young children. These data will be of great help to other researchers in analyzing the relationships between fecal SCFAs and various physiologic and pathologic conditions in early life and possibly their impact on health in adulthood.

The Effects of Helicobacter pylori Infection on Gastric Microbiota in Children With Duodenal Ulcer

Background

Helicobacter pylori (H. pylori) infection is the main cause of chronic gastritis and duodenal ulcer in children. Little is known about the effect of H. pylori on gastric microbiota in children with duodenal ulcer. This study is aimed at the characteristics of gastric microbiota in children with duodenal ulcer on H. pylori infection.

Methods

We studied 23 children diagnosed with duodenal ulcer by gastric endoscopy because of the gastrointestinal symptoms, 15 children were diagnosed with H. pylori infection, while 8 children were without H. pylori infection. Endoscopic mucosal biopsy samples were obtained for DNA extraction. Microbiomes were analyzed by 16S rRNA profiling and microbial functions were predicted using the software Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt).

Results

Bacterial richness and diversity of gastric microbiota in duodenal ulcer with H. pylori-positive were lower than those negative. The gastric microbiota in H. pylori-positive group significantly reduced proportions of six phyla and fifteen genera; only Helicobacter taxa were more abundant in H. pylori-positive group. Co-expression network analysis showed a more complex network of interactions in the H. pylori-positive group than that in the H. pylori-negative group. For the predicted functions, lower abundance in the pathways of carbohydrate metabolism, signal transduction, amino acid metabolism, and lipid metabolism were found in H. pylori-positive group than the H. pylori-negative group. H. pylori colonization reduces a microbial community with genotoxic potential in the gastric mucosa of children with duodenal ulcer.

Conclusions

The presence of H. pylori significantly influences gastric microbiota and results in a lower abundance of multiple taxonomic levels in children with duodenal ulcer. Children with duodenal ulcer exhibit a dysbiotic microbial community with genotoxic potential, which is distinct from that of children with H. pylori infection.

Clinical Trial Registration

[http://www.chictr.org.cn], identifier [ChiCTR1800015190].

Probiotic supplementation in neonates with congenital gastrointestinal surgical conditions: a pilot randomised controlled trial

OBJECTIVE

To evaluate whether probiotic supplementation attenuates gut-dysbiosis in neonates with congenital gastrointestinal surgical conditions (CGISC).

METHODS

Sixty-one neonates (≥35 weeks gestation) with CGISC were randomised to receive daily supplementation with a triple-strain bifidobacterial probiotic (n = 30) or placebo (n = 31) until discharge. Stool microbiota was analysed using 16S ribosomal RNA gene sequencing on samples collected before (T1), 1 week (T2), and 2 weeks (T3) after supplementation and before discharge (T4). The primary outcome was the sum of the relative abundance of potentially pathogenic families of Clostridiaceae, Enterobacteriaceae, Enterococcaceae, Pseudomonaceae, Staphylococcaeae, Streptococcaceae, and Yersiniaceae at T3.

RESULTS

The median gestational age [38 weeks (IQR: 37.1-38.9)] was similar in both groups. The probiotic group had lower rates of caesarean deliveries (40% versus 70%, p = 0.02). The relative abundance of potentially pathogenic families was lower in the probiotic group compared to placebo at T3 [(median: 50.4 (IQR: 26.6-67.6) versus 67.1 (IQR: 50.9-96.2); p = 0.04). Relative abundance of Bifidobacteriaceae was higher in the probiotic group at T3 [(median: 39.8 (IQR: 24.9-52.1) versus 0.03 (IQR 0.02-2.1); p < 0.001). Stratified analysis continued to show a higher abundance of Bifidobacteriaceae in the probiotic group, irrespective of the mode of delivery.

CONCLUSIONS

Probiotic supplementation attenuated gut dysbiosis in neonates with CGISC.

TRIAL REGISTRATION

http://www.anzctr.org.au (ACTRN12617001401347).

IMPACT

Probiotic supplementation attenuates gut dysbiosis and improves stool short-chain fatty acid levels in neonates with congenital gastrointestinal surgical conditions. This is the second pilot RCT of probiotic supplementation in neonates with congenital gastrointestinal conditions. These findings will pave the way for conducting multicentre RCTs in this area.