Dynamic changes of the gut microbial colonization in preterm infants with different time points after birth

Development of antibiotic resistome in premature infants

Preterm birth is a major concern in neonatal care, significantly impacting infant survival and long-term health. The gut microbiome, essential for infant development, often becomes imbalanced in preterm infants, making it crucial to understand the effects of antibiotics on its development. Our study analyzed weekly, 6-month, and 1-year stool samples from 100 preterm infants, correlating clinical data on antibiotic use and feeding patterns. Comparing infants who received no antibiotics with those given empirical post-birth treatment, we observed notable alterations in the gut microbiome's composition and an increase in antibiotic resistance gene abundance early in life. Although these effects diminished over time, their long-term clinical impacts remain unclear. Human milk feeding was associated with beneficial microbiota like Actinobacteriota and reduced antibiotic resistance genes, underscoring its protective role. This highlights the importance of judicious antibiotic use and promoting human milk to foster a healthy gut microbiome in preterm infants.

Intestinal microbiota development in the first week of life of preterm newborns

OBJECTIVE

This study aimed to evaluate the intestinal microbiota development in the first week of life of preterm newborns (PTNB) treated at a public hospital in a municipality in the Brazilian Northeast.

METHODS

This is an observational, longitudinal, and descriptive study with 23 PTNBs. Two stool samples were collected from each neonate (fasting/meconium and seventh day of life) for stool microbiota analysis by 16S rRNA gene sequencing. The authors analyzed alpha diversity (Chao1, Shannon, and Simpson indices) and principal coordinates of beta diversity.

RESULTS

Forty-six stool samples from 23 PTNBs were analyzed at the taxonomic level. Microbiota's development was dynamic with low diversity. The authors observed a statistical association with the genera Enterobacterales, Streptococcus, Bacteroides, Clostridium_sensu_stricto_1, Enterococcus, and Bifidobacterium in the fasting samples when compared to the day-7 samples. The genus Staphylococcus also dominated at both times.

CONCLUSION

Dynamics were observed in the intestinal microbiota development, with an alpha diversity decrease in the stool samples collected at fasting/meconium and on the seventh day of life.

Effect of gestational age on clinical features in necrotizing enterocolitis-associated intestinal perforation

Purpose

To investigate the clinical features of necrotizing enterocolitis-associated intestinal perforation (NEC-IP) in neonates with different gestational ages (GAs). Furthermore, we also want to identify the risk factors of poor prognosis for these patients.

Methods

The retrospective study of patients with NEC-IP was conducted with basic information, comorbidity, intraoperative findings, related treatment, and prognosis. According to the GA, patients were divided into three groups: early (GA: 28-<32 weeks, Group 1), mid-term (GA: 32-<34 weeks, Group 2), and late (GA: 34-<37 weeks, Group 3). The clinical features of the three groups were analyzed, and risk factors for poor prognosis were identified.

Results

Of the 113 cases, the number of cases in Groups 1 to 3 was 36 (31.9%), 44 (38.9%), and 33 (29.2%), respectively; and the overall proportion of poor prognosis was 19.4% (22/113). For basic information, the birth weight of Group 1 was lower than that of Group 2 and Group 3, while the postnatal day at the time of surgery of NEC and the onset age were higher than that of Group 2 (onset age: G1 12.0[7.00;20.5], G2 9.00[4.00;13.0]; postnatal day at the time of surgery: G1 22.0[13.8;27.2], G2 13.0[8.00;21.0]) (P < 0.016). For comorbidity, the incidence of sepsis, coagulopathy, type of (congenital heart disease) CHD, and hypoproteinemia in Group 1 was higher than that in Group 2 (all P < 0.016), and the incidence of respiratory failure, hypoproteinemia in Group 1 was higher than that in Group 3 (all P < 0.016). For related treatment, the usage rate of vasoactive substances and mechanical ventilation in Group 1 was higher than that of Group 2 and Group 3 (all P < 0.016). By Lasso and Logistic regression analysis, we found that GA (OR: 0.274, 95%CI: 0.078-0.796), sepsis (OR: 7.955, 95%CI: 1.424-65.21), coagulopathy (OR: 19.51, 95%CI: 3.393-179.1), CHD (OR: 6.99, 95%CI: 1.418-54.83) and diseased bowel segment (OR: 2.804, 95%CI: 1.301-7.316) were the independent factors for poor prognosis (all P < 0.05).

Conclusions

The clinical features of NEC-IP patients differ based on GA, particularly in terms of CHD type, postnatal day at the time of surgery, utilization of vasoactive substances, and prognosis. Furthermore, GA, sepsis, coagulopathy, CHD, and diseased bowel segment are independent factors for poor prognosis of patients with NEC-IP.

Dynamic impact of delivery modes on gut microbiota in preterm infants hospitalized during the initial 4 weeks of life

Preterm infants face a high risk of various complications, and their gut microbiota plays a pivotal role in health. Delivery modes have been reported to affect the development of gut microbiota in term infants, but its impact on preterm infants remains unclear. Here, we collected fecal samples from 30 preterm infants at five-time points within the first four weeks of life. Employing 16 S rRNA sequencing, principal coordinates analysis, the analysis of similarities, and the Wilcoxon rank-sum test, we examined the top dominant phyla and genera, the temporal changes in specific taxa abundance, and their relationship with delivery modes, such as Escherichia-Shigella and Enterococcus based on vaginal delivery and Pluralibacter related to cesarean section. Moreover, we identified particular bacteria, such as Taonella, Patulibacter, and others, whose proportions fluctuated among preterm infants born via different delivery modes at varying time points, as well as the microbiota types and functions. These results indicated the influence of delivery mode on the composition and function of the preterm infant gut microbiota. Importantly, these effects are time-dependent during the early stages of life. These insights shed light on the pivotal role of delivery mode in shaping the gut microbiota of preterm infants and have significant clinical implications for their care and management.

The Impact of Environmental Gaseous Pollutants on the Cultivable Bacterial and Fungal Communities of the Aerobiome

Understanding air microbial content, especially in highly polluted urban areas, is crucial for assessing its effect on human health and ecosystems. In this context, the impact of gaseous pollutants on the aerobiome remains inconclusive due to a lack of studies separating this factor from other contaminants or environmental factors. In this study, we aimed to experimentally assess the influence of contrasting concentrations of atmospheric gaseous pollutants as isolated variables on the composition of the aerobiome. Our study sites were contrasting Air Quality Index (AQI) sites of the Metropolitan Region of Chile, where nitric oxide (NO) was significantly lower at the low-AQI site than at the high-AQI site, while ozone (O3) was significantly higher. Cultivable aerobiome communities from the low-AQI site were exposed to their own pollutants or those from the high-AQI site and characterized using high-throughput sequencing (HTS), which allowed comparisons between the entire cultivable communities. The results showed increased alpha diversity in bacterial and fungal communities exposed to the high-AQI site compared to the low-AQI site. Beta diversity and compositional hierarchical clustering analyses revealed a clear separation based on NO and O3 concentrations. At the phylum level, four bacterial and three fungal phyla were identified, revealing an over-representation of Actinobacteriota and Basidiomycota in the samples transferred to the high-AQI site, while Proteobacteria were more abundant in the community maintained at the low-AQI site. At the functional level, bacterial imputed functions were over-represented only in samples maintained at the low-AQI site, while fungal functions were affected in both conditions. Overall, our results highlight the impact of NO and/or O3 on both taxonomic and functional compositions of the cultivable aerobiome. This study provides, for the first time, insights into the influence of contrasting pollutant gases on entire bacterial and fungal cultivable communities through a controlled environmental intervention.

Role of probiotics in managing various human diseases, from oral pathology to cancer and gastrointestinal diseases

The imbalance of microbial composition and diversity in favor of pathogenic microorganisms combined with a loss of beneficial gut microbiota taxa results from factors such as age, diet, antimicrobial administration for different infections, other underlying medical conditions, etc. Probiotics are known for their capacity to improve health by stimulating the indigenous gut microbiota, enhancing host immunity resistance to infection, helping digestion, and carrying out various other functions. Concurrently, the metabolites produced by these microorganisms, termed postbiotics, which include compounds like bacteriocins, lactic acid, and hydrogen peroxide, contribute to inhibiting a wide range of pathogenic bacteria. This review presents an update on using probiotics in managing and treating various human diseases, including complications that may emerge during or after a COVID-19 infection.