Bloodstream infections due to Peptoniphilus spp.: report of 15 cases

Impact of maternal obesity and mode of delivery on the newborn skin and oral microbiomes

Introduction. Previous studies have shown vast differences in the skin and oral microbiomes of newborns based on delivery method [Caesarean section (C-section) vs vaginal]. Exposure to or absence of certain bacteria during delivery can impact the neonate's future susceptibility to infections, allergies or autoimmunity by altering immune functions. Few studies have focused on the impact of maternal obesity on the variations of newborn skin and oral microbiomes. Obese pregnant women typically have a higher vaginal microbiome diversity, and their pregnancies are at higher risk for adverse outcomes and complications.Hypothesis. We hypothesized that the skin and oral microbiomes of newborns born to obese mothers would include more diverse, potentially pathogenic bacteria and that the skin and oral microbiome in C-section delivered newborns would be less diverse than vaginally delivered newborns.Aim. We aim to begin to establish maternal obesity and mode of delivery as factors contributing to increased risk for negative newborn outcomes through impacts on newborn bacterial dysbiosis.Methodology. A skin swab was collected immediately following delivery of 39 newborns from 13 healthy weight body mass index (BMI 18.50-24.99), 11 overweight (BMI 25.0-29.99) and 15 obese (BMI ≥30.00) pregnant participants. An oral swab was collected immediately following delivery for 38 of these newborns from 13 healthy weight, 10 overweight and 15 obese pregnant participants. Bacterial genera were identified via 16S rRNA amplicon sequencing.Results. The newborn skin microbiome was comprised of typical skin bacteria (i.e. Corynebacterium). Newborns of obese participants had a higher relative abundance of Peptoniphilus in their skin microbiome compared to newborns of healthy weight participants (P=0.007). Neonates born via C-section had a higher relative abundance of Ureaplasma in their oral microbiome compared to neonates delivered vaginally (P=0.046).Conclusion. We identified differences in the newborn skin and oral microbiomes based on pre-pregnancy BMI and method of delivery. These differences could be linked to an increased risk of allergies, autoimmune disease and infections. Future longitudinal studies will be crucial in determining the long-term impact of these specific genera on newborn outcomes. Understanding these connections could lead to targeted interventions that reduce the risk of adverse outcomes and improve overall health trajectory.

Cross-laboratory replication of pseudomyxoma peritonei tumor microbiome reveals reproducible microbial signatures

Recent work has demonstrated that cancer-specific microbial communities often colonize tumor tissues. However, untangling low-biomass signals from environmental contamination makes this research technically challenging. We utilize pseudomyxoma peritonei (PMP), a cancer characterized by the spread of mucus-secreting cells throughout the peritoneal cavity, to develop a robust workflow for identifying reproducible tumor microbiomes. Typically originating from the rupture of an appendiceal tumor into the peritoneal cavity, metastasized tumors have been previously shown to harbor a core set of microbes. However, that work did not control for the potential contamination of these low microbial biomass samples. We expand upon these prior findings by characterizing the microbiome of 70 additional PMP tumors and six normal peritoneal control tissues along with appropriate laboratory controls. Additionally, DNA from a subset of 25 tissues was extracted and sequenced at an independent laboratory. We found evidence of reproducible microbial signatures between the replicates of six different PMP tumors that include a set of core taxa that may be introduced from surgical contamination, as well as patient-specific taxa that are also commonly implicated in colorectal cancer. In addition, preoperative chemotherapy treatment was found to reduce tumor microbiome diversity. Our findings demonstrate how independent sample replication can be a powerful approach to investigate low-biomass microbial communities associated with tumor tissues that will improve low microbial biomass research.IMPORTANCERecent work has demonstrated that microbial communities colonize over 30 different types of tumor tissues. The origin of these communities and their possible involvement in carcinogenesis or cancer treatment outcomes remains an unclear, yet important area of research. A current major challenge in characterizing low-biomass, tumor-associated microbiomes is the introduction of environmental contamination during collection, handling, DNA extraction, PCR, and sequencing. Here, we provide a framework for replicating low-biomass tumor microbiome samples to help identify tumors with robust microbial signals and low background contamination. Using this replication approach, we show that pseudomyxoma peritonei (PMP) tumors host reproducible microbial communities, including organisms that have previously been associated with colorectal cancer. Incorporating sample replication into future tumor microbiome studies is a promising approach that will help identify robust signals and increase reproducibility in the field.

Integrated multi-omics reveals the Bacillus amyloliquefaciens BA40 against Clostridium perfringens infection in weaned piglets

INTRODUCTION

Clostridium perfringens (C. perfringens) can cause necrotic enteritis and higher mortality rates in piglets, by impairing the intestinal barrier function. Bacillus amyloliquefaciens 40 (BA40) has showed potential ability to reduce C. perfringens infections, but the mechanisms responsible for its effectiveness remain unclear.

OBJECTIVES

This study aims to evaluate the impact of BA40 on inflammation induced by C. perfringens and to explain the mechanisms underlying its therapeutic effects. We aim to show how BA40 can bolster piglet health by strengthening the intestinal barrier and regulating immune responses.

METHODS

We used piglets and cellular models, alongside microbiomics, metabolomic, and transcriptomic analyses, to investigate BA40's impact on C. perfringens-induced inflammation. A model of C. perfringens infection was constructed using piglets and cells to investigate the effect of BA40 on its phenotype. Microbiomics, metabolomics, and transcriptomics analyses were subsequently used to investigate the mechanisms of protection and immune response to BA40 on the intestinal barrier of piglets.

RESULTS

Our study revealed significant improvements in piglet health following BA40 administration. Notably, BA40 strengthened the intestinal mucosal barrier and mitigated the inflammatory response triggered by C. perfringens BA40 decreased harmful bacteria and increased beneficial bacteria. Metabolite profiles improved, showing a reduction in harmful substances. Transscriptomics analysis indicated BA40's role in TNF/NF-κB signaling pathway, hinting at its ability to regulate immune responses and reduce intestinal inflammation. Cellular assays further confirmed BA40's capacity to diminish inflammatory cytokine release and encourage the differentiation of anti-inflammatory macrophages.

CONCLUSION

Datasets from the present study demonstrate that BA40 modulates gut microbes and metabolites, inhibits inflammation-related signaling pathways, and maintains gut barrier function. Our findings not only deepen our understanding of the therapeutic capacity of BA40 but also provide a theoretical foundation for the development of probiotics and alternative therapies aimed at improving piglet gut health.

Case report: Tracing in parallel the salivary and gut microbiota profiles to assist Larotrectinib anticancer treatment for NTRK fusion-positive glioblastoma

Oncotherapy can shape intestinal microbiota, which, in turn, may influence therapy effectiveness. Furthermore, microbiome signatures during treatments can be leveraged for the development of personalised therapeutic protocols in cancer treatment based on the identification of microbiota profiles as prognostic tools. Here, for the first time, the trajectory of gut and salivary microbiota in a patient treated with Larotrectinib, a targeted therapy approved for diagnosed glioblastoma multiforme neurotrophic tyrosine receptor kinase (NTRK) gene fusion-positive, has been accurately investigated. We based our analyses on histological diagnosis, genomic and epigenomic profiling of tumour DNA, and faecal and salivary full-length 16S rRNA gene sequencing. The study clearly evidenced a remodelling of the bacterial communities following 1 month of the NTRK-inhibitor treatment, at both gut and oral levels. We reported a boosting of specific bacteria also described in response to other chemotherapeutic approaches, such as Enterococcus faecium, E. hirae, Akkermansia muciniphila, Barnesiella intestinihominis, and Bacteroides fragilis. Moreover, several bacterial species were similarly modulated upon Larotrectinib in faecal and saliva samples. Our results suggest a parallel dynamism of microbiota profiles in both body matrices possibly useful to identify microbial biomarkers as contributors to precision medicine in cancer therapies.

Anaerobic bacteria dominate the cholesteatoma tissue of chronic suppurative otitis media patients

The aim of this study was to investigate both the microbial composition and absolute abundance of clinically relevant bacteria in tissue specimens from patients with chronic suppurative otitis media with cholesteatoma (CSOM with cholesteatoma). Mastoid mucosa and cholesteatoma tissue from eleven subjects with CSOM with cholesteatoma, and mastoid mucosa from ten controls were examined using standard hospital culture swabs, Gram staining, bacterial 16S rRNA gene sequencing, Droplet Digital PCR (ddPCR), and multiplex PCR. Positive results from culture swabs were reported in half the CSOM with cholesteatoma samples and 1 control sample. In contrast, ddPCR detected bacterial genes copies in all 11 mucosa and cholesteatoma of CSOM subjects and 3 control samples. The average bacterial gene copies in tissue samples with CSOM with cholesteaotoma (1.6 ± 0.7 log10) was significantly higher compared to healthy controls (0.3 ± 1.6). These results were corroborated with Gram-staining that identified the large presence of Gram-positive cocci cells in the cholesteatoma tissue of CSOM subjects which were not seen in the mucosa of controls. The most abundant genus detected by sequencing in the mucosa and cholesteatoma of CSOM samples was Anaerococcus (93.5 % of all reads), and genus Meiothermus (0.9 %) in the control sample. The 3 samples with the highest sequencing reads (>300) were further analysed using multiplex PCR to identify the dominant Anaerococcus species. Anaerococcus hydrogenalis was the dominant species identified in these samples. In contract, commonly named ear pathogens, genera Staphylococcus and Pseudomonas, were detected in low numbers (<0.001 % of all sequencing reads) and low prevalence (2/16 samples) in the tissue samples of this study. The results show that culture severely underestimated the bacterial diversity in CSOM samples and investigating tissue rather than standard culture swabs might be advantageous to understanding the disease process. The high abundance of bacteria and the large presence of Gram-positive cells detected in the cholesteatoma tissue of CSOM compared to mucosa of CSOM or controls could be members from the genus Anaerococcus. Anaerococcus may well be a pathogen in CSOM with cholesteatoma, but their role in this condition requires further investigation.

Empyema Caused by Peptoniphilus asaccharolyticus and Complicated by Secondary Pulmonary Infection from Acinetobacter baumannii: A Case Report

Peptoniphilus asaccharolyticus is a gram-positive anaerobic coccus that can cause infections in immunocompromised individuals. P. asaccharolyticus causing empyema has not been reported earlier. Here, we present a novel case of empyema caused by P. asaccharolyticus. A 72-year-old male had a constant fever with difficulty breathing. A chest computed tomography scan revealed infiltration in the right lower lobe and pleural effusion. Following hospital admission, pleural fluid drainage was conducted, and the culture isolated P. asaccharolyticus. Initially treated with piperacillin/tazobactam, the patient experienced excessive thick sputum production, prompting a tracheostomy. Subsequent sputum cultures identified Acinetobacter baumannii. After transitioning to cefoperazone/sulbactam for antibiotic treatment and continued pleural effusion drainage, recovery was achieved. Empyema can be caused by P. asaccharolyticus and further complicated by a secondary infection with A. baumannii. Management should include appropriate antibiotic therapy, pleural drainage, vigilant monitoring, and supportive care. We aim to raise clinicians' awareness of the potential for P. asaccharolyticus to cause empyema in immunocompromised patients and to provide early treatments, thereby improving morbidity and mortality.

Impact of obesity on the perinatal vaginal environment and bacterial microbiome: effects on birth outcomes

Introduction. Lactobacillus species predominate the human vagina and are associated with positive vaginal health, including an acidic pH (<4.5). The prevalence of vaginal Lactobacilli increases with increased oestrogen due to increased glycogen production within the vagina. Lactobacilli produce lactic acid, thereby lowering vaginal pH, preventing growth of other bacteria, and lowering microbial diversity. Lower placental oestrogen levels in obese pregnant women could dampen the mechanism to initiate this process, which may be associated with vaginal dysbiosis and unfavourable pregnancy outcomes.Hypothesis. We hypothesize that oestrogen and glycogen levels will be lower, vaginal pH will be higher, and vaginal microbiome diversity will be greater during pregnancy in obese and overweight women compared to healthy weight women.Aim. Pregnancy complications (e.g. preterm birth) are more common in overweight and obese women. If vaginal dysbiosis plays a role, and quantifiable predictors of this increased risk can be determined, these measures could be used to prospectively identify women at risk for pregnancy complications early in pregnancy.Methodology. Vaginal samples were collected at 10-14, 18-24, 26-30, and 34-37 weeks gestation and at delivery from 67 pregnant participants (23 healthy weight, 22 overweight, 22 obese). A blood sample to quantify serum oestrogen was collected at 10-14 weeks. Vaginal samples were collected to test vaginal pH using pH paper, glycogen abundance using fluorometry, and the vaginal microbiome using 16S rRNA amplicon sequencing.Results. Vaginal pH was higher in obese participants compared to healthy weight participants (P=<0.001). Vaginal glycogen levels increased over time in obese participants (P=0.033). The vaginal bacterial alpha diversity was higher in obese participants compared to healthy weight participants (P=0.033). The relative abundances of Peptoniphilus and Anaerococcus were increased in overweight and obese participants, as well as in complicated pregnancies, at 10-14 weeks gestation.Conclusion. The relative abundance of specific vaginal bacteria, like Peptoniphilus and Anaerococcus, in early pregnancy could predict pregnancy outcomes. Our goal is to use the information gathered in this pilot study to further determine the feasibility of assessing the vaginal environment during pregnancy to identify women at risk for negative pregnancy and birth outcomes in the context of a larger study.

Bacterial community structure of Physalis peruviana L. fruit exocarp and the presence of pathogens with possible implications on food safety

Introduction

Cape gooseberry (Physalis peruviana L.) is a wellconsumed crop in Ecuador, whose fruits are abundant in bioactive molecules. Its rapid post-harvest deterioration and safety limit its market potential.

Methodology

To gather baseline data on the prevalence of bacterial taxa among groups, we employed 16S ribosomal RNA (16S rRNA) amplicon gene sequencing to detect changes in the bacterial community structure in cape gooseberry fruits harvested from an organic farm production system (# 270 samples x two ripeness stages), and fruits obtained from an open-air market (#270).

Results

This is the first report of bacterial taxa inhabiting cape gooseberry fruits. Shannon's diversity index revealed that the fruits purchased from the market and the unripe stage had the highest level of bacterial diversity (average Shannon indices of 3.3 and 3.1) followed by those collected from the field at the mature ripe stage (2.07). Alpha diversity analysis indicated that there were no significant differences in the number of taxa or evenness within the sample, whereas there was a significant difference in beta diversity between the groups. Rhizobiaceae was the most abundant family in fruits originating from the field regardless of the ripe stage, while Acetobacteraceae, Pseudomonadaceae, Fusobacteriaceae, Bacteroidaceae, and Erwiniaceae were the most abundant families in the market group. At the genus level, Liberibacter was the most abundant phytopathogen in fruits originating from the field, while Gluconobacter was the most abundant in samples collected from the market. The phytopathogen Candidatus_Liberibacter was the most abundant in samples collected from the field, while the fruits purchased from the market stands contained opportunistic enteric pathogens such as Escherichia vulneris, Klebsiella pneumoniae, and K. variicola, their relative abundance varied with the sample. In addition, potential pathogens of animal origin such as Fusobacterium necrophorum, Porphyromonas levii, Helcococcus ovis, and Trueperella pyogenes were found in almost all samples at varying relative abundance.

Conclusion

Our study provides basic information on the microbiome of cape gooseberries from agriculture fields to the table along with the detection of several pathogenic microorganisms with possible impact on food safety and public health therefore, strategies for reducing bacterial contamination in both farm and retail markets are compulsory.

Phylogenomic and molecular markers based studies on clarifying the evolutionary relationships among Peptoniphilus species. Identification of several Genus-Level clades of Peptoniphilus species and transfer of some Peptoniphilus species to the genus Aedoeadaptatus

To clarify the evolutionary relationships among Peptoniphilus species, whose members show association with increased risk for prostate cancer, detailed phylogenomic and comparative analyses were conducted on their genome sequences. In phylogenetic trees based on core genome proteins and 16S rRNA gene sequences, Peptoniphilus species formed eight distinct clades, with Aedoeadaptatus and Anaerosphaera species branching between them. The observed clades designated as Peptoniphilus sensu stricto (encompassing its type species), Harei, Lacrimalis, Duerdenii, Mikwangii, Stercorisuis, Catoniae and Aedoeadaptatus, show genus level divergence based on 16S rRNA similarity and average amino acid identity (AAI). The Genome Taxonomy Database also assigns most of these clades to distinct taxa. Several Peptoniphilus species (viz. P. coxii, P. ivorii, P. nemausensis and some non-validly published species) grouped reliably with the type species of Aedoeadaptatus (A. acetigenes) and are affiliated to this genus based on 16S rRNA similarity, AAI, and multiple uniquely shared molecular signatures. Hence, we are proposing the transfer of these species into the emended genus Aedoeadaptatus. Our analyses on protein sequences from Peptoniphilus genomes have also identified 54 novel molecular markers consisting of conserved signature indels (CSIs), which are specific for different Peptoniphilus species clades and provide reliable means for their demarcation in molecular terms. Lastly, we also show that based on the shared presence of these CSIs in the genomes of uncharacterized Peptoniphilus spp. (cultured and uncultured), their affiliations to the specific Peptoniphilus clades can be accurately predicted. These results should prove useful in understanding the potential involvement of Peptoniphilus-related species in diseases.

Gut microbiota composition in patients with Crohn's disease in Saudi Arabia

Crohn's disease (CD) entails intricate interactions with gut microbiome diversity, richness, and composition. The relationship between CD and gut microbiome is not clearly understood and has not been previously characterized in Saudi Arabia. We performed statistical analysis about various factors influencing CD activity and microbiota dysbiosis, including diagnosis, treatment, and its impact on their quality of life as well as high-throughput metagenomic V3-V4 16S rRNA encoding gene hypervariable region of a total of eighty patients with CD, both in its active and inactive state with healthy controls. The results were correlated with the demographic and lifestyle information, which the participants provided via a questionnaire. α-diversity measures indicated lower bacterial diversity and richness in the active and inactive CD groups compared to the control group. Greater dysbiosis was observed in the active CD patients compared to the inactive form of the disease, showed by a reduction in microbial diversity. Specific pathogenic bacteria such as Filifactor, Peptoniphilus, and Sellimonas were identified as characteristic of CD groups. In contrast, anti-inflammatory bacteria like Defluviitalea, Papillibacter, and Petroclostridium were associated with the control group. Among the various factors influencing disease activity and microbiota dysbiosis, smoking emerged as the most significant, with reduced α-diversity and richness for the smokers in all groups, and proinflammatory Fusobacteria was more present (p<0.05). Opposite to the control group, microbial diversity and richness were lower in CD participants of older age compared to younger ones, and male CD participants showed less diversity compared to women participants from the same groups. Our results describe the first report on the relationship between microbiota and Crohn's disease progress in Saudi Arabia, which may provide a theoretical basis for the application of therapeutic methods to regulate gut microbes in CD.

Longitudinal profiling of the microbiome at four body sites reveals core stability and individualized dynamics during health and disease

To understand the dynamic interplay between the human microbiome and host during health and disease, we analyzed the microbial composition, temporal dynamics, and associations with host multi-omics, immune, and clinical markers of microbiomes from four body sites in 86 participants over 6 years. We found that microbiome stability and individuality are body-site specific and heavily influenced by the host. The stool and oral microbiome are more stable than the skin and nasal microbiomes, possibly due to their interaction with the host and environment. We identify individual-specific and commonly shared bacterial taxa, with individualized taxa showing greater stability. Interestingly, microbiome dynamics correlate across body sites, suggesting systemic dynamics influenced by host-microbial-environment interactions. Notably, insulin-resistant individuals show altered microbial stability and associations among microbiome, molecular markers, and clinical features, suggesting their disrupted interaction in metabolic disease. Our study offers comprehensive views of multi-site microbial dynamics and their relationship with host health and disease.

Peptoniphilus genitalis sp. nov. and Mobiluncus massiliensis sp. nov.: Novel Bacteria Isolated from the Vaginal Microbiome

The strains Marseille-Q7072T (= CSUR Q7072T = CECT 30604 T) and Marseille-Q7826T (= CSUR Q7826T = CECT 30727 T) were isolated from vaginal samples. As MALDI-TOF mass spectrometry failed to identify them, their genomes were directly sequenced to determine their taxogenomic identities. Both strains are anaerobic without any oxidase and catalase activity. C16:0 is the most abundant fatty acid for both strains. Strain Marseille-Q7072T is non-spore-forming, non-motile, Gram-stain-positive, and coccus-shaped, while strain Marseille-Q7826T is non-spore-forming, motile, Gram-stain-variable, and curved rod-shaped. The genomic comparison of the Marseille-Q7072T and Marseille-Q7826T strains showed that all digital DNA-DNA hybridisation (dDDH) and mean orthologous nucleotide identity (OrthoANI) values were below published species thresholds (70% and 95-96%, respectively) with other closely related species with standing in nomenclature. Thus, we conclude that both strains are new bacterial species. Strain Marseille-Q7072T is a new member of the Bacillota phylum, for which the name Peptoniphilus genitalis sp. nov. is proposed, while the Marseille-Q7826T strain is a new member of the Actinomycetota phylum, for which the name Mobiluncus massiliensis sp. nov. is proposed.

The impact of faecal diversion on the gut microbiome: a systematic review

Diversion of the faecal stream is associated with diversion colitis (DC). Preliminary studies indicate that microbiome dysbiosis contributes to its development and potentially treatment. This review aims to characterise these changes in the context of faecal diversion and identify their clinical impact. A systematic search was conducted using MEDLINE, EMBASE and CENTRAL databases using a predefined search strategy identifying studies investigating changes in microbiome following diversion. Findings reported according to PRISMA guidelines. Of 743 results, 6 met inclusion criteria. Five reported significantly decreased microbiome diversity in the diverted colon. At phylum level, decreases in Bacillota with a concomitant increase in Pseudomonadota were observed, consistent with dysbiosis. At genus level, studies reported decreases in beneficial lactic acid bacteria which produce short-chain fatty acid (SCFA), which inversely correlated with disease severity. Significant losses in commensals were also noted. These changes were seen to be partially reversible with restoration of bowel continuity. Changes within the microbiome were reflected by histopathological findings suggestive of intestinal dysfunction. Faecal diversion is associated with dysbiosis in the diverted colon which may have clinical implications. This is reflected in loss of microbiome diversity, increases in potentially pathogenic-associated phyla and reduction in SCFA-producing and commensal bacteria.

Longitudinal profiling of the microbiome at four body sites reveals core stability and individualized dynamics during health and disease

To understand dynamic interplay between the human microbiome and host during health and disease, we analyzed the microbial composition, temporal dynamics, and associations with host multi-omics, immune and clinical markers of microbiomes from four body sites in 86 participants over six years. We found that microbiome stability and individuality are body-site-specific and heavily influenced by the host. The stool and oral microbiome were more stable than the skin and nasal microbiomes, possibly due to their interaction with the host and environment. Also, we identified individual-specific and commonly shared bacterial taxa, with individualized taxa showing greater stability. Interestingly, microbiome dynamics correlated across body sites, suggesting systemic coordination influenced by host-microbial-environment interactions. Notably, insulin-resistant individuals showed altered microbial stability and associations between microbiome, molecular markers, and clinical features, suggesting their disrupted interaction in metabolic disease. Our study offers comprehensive views of multi-site microbial dynamics and their relationship with host health and disease.

Study Highlights

The stability of the human microbiome varies among individuals and body sites.Highly individualized microbial genera are more stable over time.At each of the four body sites, systematic interactions between the environment, the host and bacteria can be detected.Individuals with insulin resistance have lower microbiome stability, a more diversified skin microbiome, and significantly altered host-microbiome interactions.

Falcon gut microbiota is shaped by diet and enriched in Salmonella

The gut microbiome is increasingly being appreciated as a master regulator of animal health. However, avian gut microbiome studies commonly focus on birds of economic importance and the gut microbiomes of raptors remain underexplored. Here we examine the gut microbiota of 29 captive falcons-raptors of historic importance-in the context of avian evolution by sequencing the V4 region of the 16S rRNA gene. Our results reveal that evolutionary histories and diet are significantly associated with avian gut microbiota in general, whereas diet plays a major role in shaping the falcon gut microbiota. Multiple analyses revealed that gut microbial diversity, composition, and relative abundance of key diet-discriminating bacterial genera in the falcon gut closely resemble those of carnivorous raptors rather than those of their closest phylogenetic relatives. Furthermore, the falcon microbiota is dominated by Firmicutes and contains Salmonella at appreciable levels. Salmonella presence was associated with altered functional capacity of the falcon gut microbiota as its abundance is associated with depletion of multiple predicted metabolic pathways involved in protein mass buildup, muscle maintenance, and enrichment of antimicrobial compound degradation, thus increasing the pathogenic potential of the falcon gut. Our results point to the necessity of screening for Salmonella and other human pathogens in captive birds to safeguard both the health of falcons and individuals who come in contact with these birds.

Gut microbial ecology and exposome of a healthy Pakistani cohort

BACKGROUND

Pakistan is a multi-ethnic society where there is a disparity between dietary habits, genetic composition, and environmental exposures. The microbial ecology of healthy Pakistani gut in the context of anthropometric, sociodemographic, and dietary patterns holds interest by virtue of it being one of the most populous countries, and also being a Lower Middle Income Country (LMIC).

METHODS

16S rRNA profiling of healthy gut microbiome of normo-weight healthy Pakistani individuals from different regions of residence is performed with additional meta-data collected through filled questionnaires. The current health status is then linked to dietary patterns through [Formula: see text] test of independence and Generalized Linear Latent Variable Model (GLLVM) where distribution of individual microbes is regressed against all recorded sources of variability. To identify the core microbiome signature, a dynamic approach is used that considers into account species occupancy as well as consistency across assumed grouping of samples including organization by gender and province of residence. Fitting neutral modeling then revealed core microbiome that is selected by the environment.

RESULTS

A strong determinant of disparity is by province of residence. It is also established that the male microbiome is better adapted to the local niche than the female microbiome, and that there is microbial taxonomic and functional diversity in different ethnicities, dietary patterns and lifestyle habits. Some microbial genera, such as, Megamonas, Porphyromonas, Haemophilus, Klebsiella and Finegoldia showed significant associations with consumption of pickle, fresh fruits, rice, and cheese. Our analyses suggest current health status being associated with the diet, sleeping patterns, employment status, and the medical history.

CONCLUSIONS

This study provides a snapshot of the healthy core Pakistani gut microbiome by focusing on the most populous provinces and ethnic groups residing in predominantly urban areas. The study serves a reference dataset for exploring variations in disease status and designing personalized dietary and lifestyle interventions to promote gut health, particularly in LMICs settings.

Bacterial dysbiosis and epithelial status of the California sea lion (Zalophus californianus) in the Gulf of California

Despite the high incidence of urogenital carcinoma (UGC) in California sea lions stranded along California, no UGC has been reported in other areas of their distribution; however, cell morphologies typical of premalignant states have been found. Risk factors for UGC include high of organochlorines and infection with a gammaherpesvirus, OtHV-1, but the importance of the bacteriome for epithelial status remains unknown. We characterized the genital bacteriome of adult female California sea lions along their distribution in the Gulf of California and examined whether the diversity and abundance of the bacteriome varied spatially, whether there were detectable differences in the bacteriome between healthy and altered epithelia, and whether the bacteriome was different in California sea lions infected with OtHV-1 or papillomavirus. We detected 2270 ASVs in the genital samples, of which 35 met the criteria for inclusion in the core bacteriome. Fusobacteriia and Clostridia were present in all samples, at high abundances, and Actinobacteria, Alphaproteobacteria, and Campylobacteria were also well-represented. Alpha diversity and abundance of the California sea lion genital bacteriome varied geographically. The abundance of bacterial ASVs varied depending on the genital epithelial status and inflammation, with differences driven by classes Fusobacteriia, Clostridia, Campylobacteria and Alphaproteobacteria. Alpha diversity and abundance were lowest in samples in which OtHV-1 was detected, and highest those with papillomavirus. Our study is the first investigation of how the bacteriome is related to epithelial status in a wild marine species prone to developing cancer.

A Cryptic Case of an Anaerobic Hepatic Abscess Following a Cesarean Section

Postpartum infectious complications can present with a wide range of nonspecific symptoms. Herein, we describe a complicated late postpartum presentation of recurrent fever following a cesarean delivery complicated by chorioamnionitis. Following discharge, the patient experienced cyclical fever and was treated with antipyretics as an outpatient. The patient continued to experience symptoms and reported to the hospital for further evaluation. Initially thought to be septic pelvic thrombophlebitis, the patient was trialed on clindamycin and gentamycin without resolution of symptoms. After extensive evaluation, the fevers were found to be the result of an infected periuterine hematoma and a concomitant subcapsular inferior hepatic abscess. Bacterial cultures isolated two rare anaerobic organisms: Peptoniphilus ssp. and Finegoldia magna. Source control was achieved by drainage of the two abscesses followed by antibiotic treatment with ertapenem and metronidazole, and the patient recovered successfully. This is the first reported case, to the authors' knowledge, of this complicated postpartum picture due to these anaerobic organisms.

HPV-related anal cancer is associated with changes in the anorectal microbiome during cancer development

Background

Squamous cell carcinoma of the anus (SCCA) is a rare gastrointestinal cancer. Factors associated with progression of HPV infection to anal dysplasia and cancer are unclear and screening guidelines and approaches for anal dysplasia are less clear than for cervical dysplasia. One potential contributing factor is the anorectal microbiome. In this study, we aimed to identify differences in anal microbiome composition in the settings of HPV infection, anal dysplasia, and anal cancer in this rare disease.

Methods

Patients were enrolled in two prospective studies. Patients with anal dysplasia were part of a cross-sectional cohort that enrolled women with high-grade lower genital tract dysplasia. Anorectal tumor swabs were prospectively collected from patients with biopsy-confirmed locally advanced SCCA prior to receiving standard-of-care chemoradiotherapy (CRT). Patients with high-grade lower genital tract dysplasia without anal dysplasia were considered high-risk (HR Normal). 16S V4 rRNA Microbiome sequencing was performed for anal swabs. Alpha and Beta Diversity and composition were compared for HR Normal, anal dysplasia, and anal cancer.

Results

60 patients with high-grade lower genital tract dysplasia were initially enrolled. Seven patients had concurrent anal dysplasia and 44 patients were considered HR Normal. Anorectal swabs from 21 patients with localized SCCA were included, sequenced, and analyzed in the study. Analysis of weighted and unweighted UniFrac distances demonstrated significant differences in microbial community composition between anal cancer and HR normal (p=0.018). LEfSe identified that all three groups exhibited differential enrichment of specific taxa. Peptoniphilus (p=0.028), Fusobacteria (p=0.0295), Porphyromonas (p=0.034), and Prevotella (p=0.029) were enriched in anal cancer specimens when compared to HR normal.

Conclusion

Although alpha diversity was similar between HR Normal, dysplasia and cancer patients, composition differed significantly between the three groups. Increased anorectal Peptoniphilus, Fusobacteria, Porphyromonas, and Prevotella abundance were associated with anal cancer. These organisms have been reported in various gastrointestinal cancers with roles in facilitating the proinflammatory microenvironment and neoplasia progression. Future work should investigate a potential role of microbiome analysis in screening for anal dysplasia and investigation into potential mechanisms of how these microbial imbalances influence the immune system and anal carcinogenesis.

Septic Abortion Secondary to Peptoniphilus asaccharolyticus Complicated by Bacteremia: A Case Report and Review of Literature

Peptoniphilus species are gram-positive anaerobic coccus (GPAC) that are found in the human flora, such as the skin, gastrointestinal tract, and genitourinary tract, and can be pathogenic. Septic abortion caused by Peptoniphilus species has been reported only three times in the literature. Here, we present a case of Peptoniphilus asaccharolyticus (P. asaccharolyticus) bacteremia as a complication of septic abortion.

Analysis of Neutrophil and Monocyte Inflammation Markers in Response to Gram-Positive Anaerobic Cocci

The impact of anaerobic bacteria on the human host is sparsely investigated due to cultivation challenges. Nonetheless, in the last decade increasing research demonstrated the importance of paying attention to these overlooked pathogens. In this chapter, we provide an overview of analyzing surface and intracellular inflammation markers of neutrophils and monocytes in response to Gram-positive anaerobic cocci (GPAC) species Peptoniphilus (P.) harei.

The role of intraamniotic inflammation in threatened midtrimester miscarriage

BACKGROUND

The assessment and management of patients with threatened midtrimester miscarriage is a clinical challenge because the etiology of this condition is poorly understood.

OBJECTIVE

This study aimed to examine the frequency of intraamniotic infection or inflammation and the effect of antibiotics in patients presenting with regular uterine contractions and intact membranes before 20 weeks of gestation.

STUDY DESIGN

This retrospective study comprised patients who met the following criteria: (1) singleton gestation, (2) gestational age before 20 weeks, (3) the presence of regular uterine contractions confirmed by a tocodynamometer (8 or more contractions in 60 minutes), (4) intact amniotic membranes, and (5) transabdominal amniocentesis performed for the evaluation of the microbiologic and inflammatory status of the amniotic cavity. Samples of amniotic fluid were cultured for aerobic and anaerobic bacteria and genital mycoplasmas, and polymerase chain reaction was performed to detect Ureaplasma species. Amniotic fluid was tested for white blood cell counts and matrix metalloproteinase-8 concentrations to diagnose intraamniotic inflammation. Patients with intraamniotic inflammation, or intraamniotic infection, were treated with antibiotics (a combination of ceftriaxone, clarithromycin, and metronidazole). Treatment success was defined as the resolution of intraamniotic infection/inflammation at the follow-up amniocentesis or delivery after 34 weeks of gestation.

RESULTS

1) Intraamniotic inflammation was present in 88% (15/17) of patients, whereas infection was detectable in only 2 cases; 2) objective evidence of resolution of intraamniotic inflammation after antibiotic treatment was demonstrated in 100% (4/4) of patients who underwent a follow-up amniocentesis; 3) 30% (5/15) of women receiving antibiotics delivered after 34 weeks of gestation (3 of the 5 patients had a negative follow-up amniocentesis, and 2 of the women were without a follow-up amniocentesis); 4) the overall treatment success of antibiotics was 40% (6/15; 4 cases of objective evidence of resolution of intra-amniotic inflammation and 5 cases of delivery after 34 weeks of gestation).

CONCLUSION

The prevalence of intraamniotic inflammation in patients who presented with a threatened midtrimester miscarriage was 88% (15/17), and, in most cases, microorganisms could not be detected. Antibiotic treatment, administered to patients with intraamniotic inflammation, was associated with either objective resolution of intraamniotic inflammation or delivery after 34 weeks of gestation in 40% (6/15) of the cases.

Identification of Peptoniphilus vaginalis-Like Bacteria, Peptoniphilus septimus sp. nov., From Blood Cultures in a Cervical Cancer Patient Receiving Chemotherapy: Case and Implications

A 39-year-old woman with a 3-year human papillomavirus (HPV) 18 infection history was admitted to the hospital for a 16-day history of vaginal bleeding after sex. She was diagnosed with cervical cancer based on the results of the electronic colposcopy, cervical cytology, microscopy, and magnetic resonance imaging (MRI). Then, she received chemotherapy, with paclitaxel 200 mg (day 1), cisplatin 75 mg (day 2), and bevacizumab 700 mg (day 3) twice with an interval of 27 days. During the examination for the diagnosis and treatment, many invasive operations, including removal of intrauterine device, colposcopy, and ureteral dilatation, were done. After that, the patient was discharged and entered the emergency department about 2.5 months later with a loss of consciousness probably caused by septic shock. The patient finally died of multiple organ failure and bacterial infection, although she has received antimicrobial therapy. The blood cultures showed a monobacterial infection with an anaerobic Gram-positive bacterial strain, designated as SAHP1. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI–TOF MS) indicated that the patient was infected with Peptoniphilus asaccharolyticus, while molecular analysis and genome-based taxonomy confirmed the infection with a novel Peptoniphilus species that has a close genetic relationship with Peptoniphilus vaginalis and proposed provisionally as Peptoniphilus septimus sp. nov., which may also act as a commensal of the human vagina. Genomic features of SAHP1 have been fully described, and comparative genomic analysis reveals the known prokaryote relative of Peptoniphilus septimus sp. nov. in the genus Peptoniphilus. The invasive operations on the genital tract during the diagnosis and treatment of the patient and the tumor tissue damage and bleeding may have a certain role in the bloodstream infection. This study casts a new light on the Peptoniphilus bacteria and prompts clinicians to include anaerobic blood cultures as part of their blood culture procedures, especially on patients with genital tract tumors. Furthermore, due to the incomplete database and unsatisfying resolution of the MALDI–TOF MS for Peptoniphilus species identification, molecular identification, especially whole-genome sequencing, is required for those initially identified as bacteria belonging to Peptoniphilus in the clinical laboratory.

Gut microbiota alterations in critically ill older patients: a multicenter study

Background

Aging generates changes in the gut microbiota, affecting its functionality. Little is known about gut microbiota in critically ill older adults. The objective of this study was to describe the profile of gut microbiota in a cohort of critically ill older adults.

Methods

This observational study was conducted in five health institutions. Over a 6-month study period, critically ill patients over 18 years old who were admitted to the intensive care unit were enrolled. Fecal microbiota profiles were determined from 155 individuals, over 60 years old (n = 72) and under 60 years old (n = 83). Gut microbiota was analyzed by sequencing the V3-V4 region of the 16S rRNA gene. Alpha and beta diversity, operational taxonomic units and the interaction of gut microbiota with variables under study were analyzed. Amplicon sequence variants (ASVs) specifically associated with age were recovered by including gender, discharge condition, BMI, ICU stay and antibiotics as covariates in a linear mixed model.

Results

In older adults, sepsis, malnutrition, antibiotic prescription and severity (APACHE and SOFA scores) were higher than in the group under 60 years of age. Alpha diversity showed lower gut microbiota diversity in those over 60 years of age (p < 0.05); beta diversity evidenced significant differences between the groups (PERMANOVA = 1.19, p = 0.038). The microbiota of the adults under 60 years old showed greater abundance of Murdochiella, Megasphaera, Peptoniphilus and Ezakiella, whereas those over 60 years old Escherichia-Shigella and Hungatella were more abundant.

Conclusion

The gut microbial community was altered by different factors; however, age significantly explained the variability in critically ill patients. A lower presence of beneficial genera and a higher abundance of pathogens was observed in adults over 60 years old.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-02981-0.

Septic Shock, Renal Abscess, and Bacteremia Due to Peptoniphilus asaccharolyticus in a Woman with Nephrosis and Diabetes Mellitus: Case Report and Literature Review

Peptoniphilus asaccharolyticus is a Gram-positive anaerobic coccus, which forms part of the normal flora and the human commensals of the skin, genitourinary system, and gut. It can cause opportunistic infections in immunocompromised patients and is frequently isolated as part of polymicrobial spectra. Severe monomicrobial infections caused by the genus rarely occur. In this study, we report on septic shock, renal abscess, and bacteremia due to P. asaccharolyticus in a woman with nephrosis and diabetes mellitus. To the best of our knowledge, this report is the first to describe P. asaccharolyticus isolated from both renal abscess and blood cultures purely. The underlying diseases of the host and the removal of the double J tube were significant predisposing factors in this infection.

A case of Escherichia coli and Peptoniphilus species mixed osteomyelitis successfully identified by MALDI TOF-MS with a review of the literature

BACKGROUND

Peptoniphilus species are Gram-positive anaerobic cocci that are commensals of the human vagina and gut.

METHODS AND RESULTS

We describe a case of mixed Escherichia coli and Peptoniphilus spp. osteomyelitis identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry as Peptoniphilus harei and present a short literature review.

CONCLUSION

To our knowledge, only six cases of P. harei osteomyelitis have been reported to date.

Sonication Fluid Isolation of Peptoniphilus asaccharolyticus After Total Hip Arthroplasty

Peptoniphilus asaccharolyticus is a gram-positive anaerobic coccus found on the skin, vagina, and gut, where it acts as an opportunistic pathogen or as part of polymicrobial infections of chronic wounds or diabetic ulcers. We present a case of a 68-year-old woman who was diagnosed with a late prosthetic hip arthroplasty infection caused by P. asaccharolyticus and isolated from sonication fluid cultures. Despite the fact that evidence is scarce, its role and pathogenicity in more severe infections should not be underestimated.

Identification of Peptoniphilus harei From Blood Cultures in an Infected Aortic Aneurysm Patient: Case Report and Review Published Literature

Gram-positive anaerobic cocci (GPAC) are a commensal part of human flora but are also opportunistic pathogens. This is possibly the first study to report a case of Peptoniphilus harei bacteremia in an abdominal aortic aneurysm (AAA) patient. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) failed to identify the isolate and molecular analysis confirmed it as P. harei. A comprehensive literature review revealed that P. harei is an emergent pathogen. This study serves as a reminder for practicing clinicians to include anaerobic blood cultures as part of their blood culture procedures; this is particularly important situations with a high level of suspicion of infection factors in some noninfectious diseases, as mentioned in this publication. Clinical microbiologists should be aware that the pathogenic potential of GPAC can be greatly underestimated leading to incorrect diagnosis on using only one method for pathogen identification. Upgradation and correction of the MALDI-TOF MS databases is recommended to provide reliable and rapid identification of GPAC at species level in medical diagnostic microbiology laboratories.

Long-term biodiversity intervention shapes health-associated commensal microbiota among urban day-care children

BACKGROUND

In modern urban environments children have a high incidence of inflammatory disorders, including allergies, asthma, and type1 diabetes. The underlying cause of these disorders, according to the biodiversity hypothesis, is an imbalance in immune regulation caused by a weak interaction with environmental microbes. In this 2-year study, we analyzed bacterial community shifts in the soil surface in day-care centers and commensal bacteria inhabiting the mouth, skin, and gut of children. We compared two different day-care environments: standard urban day-care centers and intervention day-care centers. Yards in the latter were amended with biodiverse forest floor vegetation and sod at the beginning of the study.

RESULTS

Intervention caused a long-standing increase in the relative abundance of nonpathogenic environmental mycobacteria in the surface soils. Treatment-specific shifts became evident in the community composition of Gammaproteobacteria, Negativicutes, and Bacilli, which jointly accounted for almost 40 and 50% of the taxa on the intervention day-care children's skin and in saliva, respectively. In the year-one skin swabs, richness of Alpha-, Beta-, and Gammaproteobacteria was higher, and the relative abundance of potentially pathogenic bacteria, including Haemophilus parainfluenzae, Streptococcus sp., and Veillonella sp., was lower among children in intervention day-care centers compared with children in standard day-care centers. In the gut, the relative abundance of Clostridium sensu stricto decreased, particularly among the intervention children.

CONCLUSIONS

This study shows that a 2-year biodiversity intervention shapes human commensal microbiota, including taxa that have been associated with immune regulation. Results indicate that intervention enriched commensal microbiota and suppressed the potentially pathogenic bacteria on the skin. We recommend future studies that expand intervention strategies to immune response and eventually the incidence of immune-mediated diseases.

Culturomic and quantitative real-time-polymerase chain reaction analyses for early contamination of abutments with different surfaces: A randomized clinical trial

BACKGROUND

Rough and/or plasma-activated abutments seem to be able to increase soft tissue adhesion and stability; however, limited evidence is available about bacterial contamination differences.

PURPOSE

The aim was to investigate the oral microbiota on four dental abutments with different surfaces by quantitative real-time polymerase chain reaction (qRT-PCR) and culturomic approach.

METHODS

Forty patients needing a single implant rehabilitation were involved in the study. Forty healing abutments, especially designed for the study, were divided into four groups according to the surface topography (1. machined [MAC], 2. machined plasma of argon treated [plasmaMAC], 3. ultrathin threaded microsurface [UTM], 4. UTM plasma of argon treated [Plasma UTM]). Random assignment was performed according to predefined randomization tables. All patients underwent surgical intervention for implant and contextual healing abutment positioning. After 2 months of healing, a sterile cotton swab was used for microbiological sampling for culturomics, while sterile paper points inserted into the sulcus were used for qRT-PCR.

RESULTS

At the end of the study, 36 patients completed all procedures and a total of 36 abutments (9 per group) were analyzed. qRT-PCR retrieved data for 23 bacterial species whereas culturomics revealed the presence of 74 different bacteria, most of them not routinely included into oral cavity microbiological kits of analysis or never found before in the oral microenvironment. No statistically significant differences emerged analyzing the four different surfaces (p = 0.053). On the contrary, higher total and specific bacterial counts were detected in the plasma-treated surfaces compared to the untreated ones (p = 0.021).

CONCLUSIONS

Abutments with different topographies and surface treatments resulted contaminated by similar oral bacterial flora. Abutments with moderately rough surface were not associated with a greater bacterial adhesion compared to machined ones. Conversely, more bacteria were found around plasma-treated abutments. Furthermore, data reported suggested to include new species not previously sought in the routine analyses of the oral bacterial microflora.

Long-read sequencing revealed cooccurrence, host range, and potential mobility of antibiotic resistome in cow feces

While it is well recognized that the environmental resistome is global, diverse, and augmented by human activities, it has been difficult to assess risk because of the inability to culture many environmental organisms, and it is difficult to evaluate risk from current sequence-based environmental methods. The four most important criteria to determine risk are whether the antibiotic-resistance genes (ARGs) are a complete, potentially functional complement; if they are linked with other resistances; whether they are mobile; and the identity of their host. Long-read sequencing fills this important gap between culture and short sequence-based methods. To address these criteria, we collected feces from a ceftiofur-treated cow, enriched the samples in the presence of antibiotics to favor ARG functionality, and sequenced long reads using Nanopore and PacBio technologies. Multidrug-resistance genes comprised 58% of resistome abundance, but only 0.8% of them were plasmid associated; fluroquinolone-, aminoglycoside-, macrolide-lincosamide-streptogramin (MLS)-, and β-lactam-resistance genes accounted for 2.7 to 12.3% of resistome abundance but with 19 to 78% located on plasmids. A variety of plasmid types were assembled, some of which share low similarity to plasmids in current databases. Enterobacteriaceae were dominant hosts of antibiotic-resistant plasmids; physical linkage of extended-spectrum β-lactamase genes (CTX-M, TEM, CMY, and CARB) was largely found with aminoglycoside-, MLS-, tetracycline-, trimethoprim-, phenicol-, sulfonamide-, and mercury-resistance genes. A draft circular chromosome of Vagococcus lutrae was assembled; it carries MLS-, tetracycline- (including tetM and tetL on an integrative conjugative element), and trimethoprim-resistance genes flanked by many transposase genes and insertion sequences, implying that they remain transferrable.

Metagenomics Analysis Reveals an Extraordinary Inner Bacterial Diversity in Anisakids (Nematoda: Anisakidae) L3 Larvae

L3 larvae of anisakid nematodes are an important problem for the fisheries industry and pose a potential risk for human health by acting as infectious agents causing allergies and as potential vectors of pathogens and microrganisms. In spite of the close bacteria-nematode relationship very little is known of the anisakids microbiota. Fresh fish could be contaminated by bacteria vectored in the cuticle or in the intestine of anisakids when the L3 larvae migrate through the muscles. As a consequence, the bacterial inoculum will be spread, with potential effects on the quality of the fish, and possible clinical effects cannot be discarded. A total of 2,689,113 16S rRNA gene sequences from a total of 113 L3 individuals obtained from fish captured along the FAO 27 fishing area were studied. Bacteria were taxonomically characterized through 1803 representative operational taxonomic units (OTUs) sequences. Fourteen phyla, 31 classes, 52 orders, 129 families and 187 genera were unambiguously identified. We have found as part of microbiome an average of 123 OTUs per L3 individual. Diversity indices (Shannon and Simpson) indicate an extraordinary diversity of bacteria at an OTU level. There are clusters of anisakids individuals (samples) defined by the associated bacteria which, however, are not significantly related to fish hosts or anisakid taxa. This suggests that association or relationship among bacteria in anisakids, exists without the influence of fishes or nematodes. The lack of relationships with hosts of anisakids taxa has to be expressed by the association among bacterial OTUs or other taxonomical levels which range from OTUs to the phylum level. There are significant biological structural associations of microbiota in anisakid nematodes which manifest in clusters of bacteria ranging from phylum to genus level, which could also be an indicator of fish contamination or the geographic zone of fish capture. Actinobacteria, Aquificae, Firmicutes, and Proteobacteria are the phyla whose abundance value discriminate for defining such structures.

Healthcare-Associated Laboratory-Confirmed Bloodstream Infections-Species Diversity and Resistance Mechanisms, a Four-Year Retrospective Laboratory-Based Study in the South of Poland

INTRODUCTION

Regardless of the country, advancements in medical care and infection prevention and control of bloodstream infections (BSIs) are an enormous burden of modern medicine.

OBJECTIVES

The aim of our study was to describe the epidemiology and drug-resistance of laboratory-confirmed BSI (LC-BSIs) among adult patients of 16 hospitals in the south of Poland.

PATIENTS AND METHODS

Data on 4218 LC-BSIs were collected between 2016-2019. The identification of the strains was performed using MALDI-TOF. Resistance mechanisms were investigated according to European Committee on Antimicrobial Susceptibility Testing, EUCAST recommendations.

RESULTS

Blood cultures were collected from 8899 patients, and LC-BSIs were confirmed in 47.4%. The prevalence of Gram-positive bacteria was 70.9%, Gram-negative 27.8% and yeast 1.4%. The most frequently isolated genus was Staphylococcus (50% of all LC-BSIs), with a domination of coagulase-negative staphylococci, while Escherichia coli (13.7%) was the most frequent Gram-negative bacterium. Over 4 years, 108 (2.6%) bacteria were isolated only once, including species from the human microbiota as well as environmental and zoonotic microorganisms. The highest methicillin resistant Staphylococcus aureus (MRSA) prevalence was in intensive care units (ICUs) (55.6%) but S. aureus with resistance to macrolides, lincosamides and streptogramins B (MLSB) in surgery was 66.7%. The highest prevalence of E. faecalis with a high-level aminoglycoside resistance (HLAR) mechanism was in ICUs, (84.6%), while E. faecium-HLAR in surgery was 83.3%. All cocci were fully glycopeptide-sensitive. Carbapenem-resistant Gram-negative bacilli were detected only in non-fermentative bacilli group, with prevalence 70% and more.

CONCLUSIONS

The BSI microbiology in Polish hospitals was similar to those reported in other studies, but the prevalence of MRSA and enterococci-HLAR was higher than expected, as was the prevalence of carbapenem-resistant non-fermentative bacilli. Modern diagnostic techniques, such as MALDI-TOF, guarantee reliable diagnosis.

Unusual cause of acute sinusitis and orbital abscess in COVID-19 positive patient: Case report

BACKGROUND

Peptoniphilus indolicus is not usually seen in the eye or paranasal sinuses but is a commensal of the human vagina and gut. However, with COVID-19, eye infections and other unusual complications are possible with such unsuspected bacteria.

CASE PRESENTATION

The patient is a 76-year-old white male from a nursing home tested positive for COVID-19 and was sent from a nursing facility for left eye drainage and psychiatric evaluation. Upon presentation, the patient was not fully oriented and could not provide a history of the eye drainage. CT scan showed sinusitis with left orbital and periorbital abscess formation, cellulitis, and extensive osteomyelitis. He underwent endoscopic transnasal drainage and orbiotomy. Cultures returned positive for methicillin-resistant Stapholococcus aureus (MRSA), Streptococcus constellatus, and Peptoniphilus indolicus. He was maintained on several days of IV antibiotics and returned to the nursing home. He then presented 2 months later and required enucleation of his globe, due to the presence of multiple scleral perforations in the setting of orbital abscess, as well as removal of necrotic orbital bone.

CONCLUSIONS

Given the concomitant infection with COVID-19 and unusual presentation, the patient's sinus cultures support the notion that COVID-19 can affect the presence of bacteria within certain anatomical regions. Specifically, Peptoniphilus indolicus is not normally found outside of the vagina or gut biome. Avascular, pale mucosa and bone of the nasal cavity was noted during surgery of this COVID-19 infected patient, which is in contrast to the friable and edematous tissue typically found in acutely infected sinuses. Our patient's orbital abscess began to drain spontaneously through the skin, which is rare for orbital abscesses. Also uncommon with orbital abscesses is the need for enucleation, which in this case was deemed necessary given that the abscess had perforated the sclera in multiple locations.

A Pilot Study: Changes of Intestinal Microbiota of Patients With Non-small Cell Lung Cancer in Response to Osimertinib Therapy

Osimertinib contributes to the higher efficacy and few intestinal side effects in non-small cell lung cancer (NSCLC) patients with T790M mutation. Previous studies has reported that intestinal microbiota play important roles in drug efficacy and toxicity. However, we have known less about the changes of intestinal microbiota in response to osimertinib therapy. In this pilot study, we used longitudinal sampling with 6 weeks sampling collection intervals for about 1 year to model intestinal microbial changes based on the 16S rRNA genes sequencing in fecal samples from NSCLC patients in response to osimertinib therapy. The results showed that there was no significantly different on the intestinal microbial composition at the phylum, family, and genus level among NSCLC patients with different treatment cycles (P > 0.05). There were no significant differences in alpha diversity characterized by the richness, Shannon diversity, and phylogenetic diversity based on the Welch’s t-test among NSCLC patients in response to osimertinib therapy (P > 0.05). However, the dissimilarity test and principal coordination analysis showed a few differences among NSCLC patients. The intestinal microbial markers were changed in post-therapy (Sutterella, Peptoniphilus, and Anaeroglobus) compared to that in pre-therapy (Clostridium XIVa). Furthermore, the phylogenetic molecular ecological networks (MENs) were influenced by osimertinib therapy based on the module number, link number, and module taxa composition of the first six groups. Overall, it indicated that osimertinib therapy changed the intestinal microbiota to some extent, though not completely. In all, this pilot study provides an understanding of changes of intestinal microbiota from NSCLC patients in response to osimertinib therapy. No complete changes in intestinal microbiota seem to be closely linked with the few intestinal side effects and higher efficacy in response to osimertinib therapy.

Performance and Application of 16S rRNA Gene Cycle Sequencing for Routine Identification of Bacteria in the Clinical Microbiology Laboratory

This review provides a state-of-the-art description of the performance of Sanger cycle sequencing of the 16S rRNA gene for routine identification of bacteria in the clinical microbiology laboratory. A detailed description of the technology and current methodology is outlined with a major focus on proper data analyses and interpretation of sequences. The remainder of the article is focused on a comprehensive evaluation of the application of this method for identification of bacterial pathogens based on analyses of 16S multialignment sequences. In particular, the existing limitations of similarity within 16S for genus- and species-level differentiation of clinically relevant pathogens and the lack of sequence data currently available in public databases is highlighted. A multiyear experience is described of a large regional clinical microbiology service with direct 16S broad-range PCR followed by cycle sequencing for direct detection of pathogens in appropriate clinical samples. The ability of proteomics (matrix-assisted desorption ionization-time of flight) versus 16S sequencing for bacterial identification and genotyping is compared. Finally, the potential for whole-genome analysis by next-generation sequencing (NGS) to replace 16S sequencing for routine diagnostic use is presented for several applications, including the barriers that must be overcome to fully implement newer genomic methods in clinical microbiology. A future challenge for large clinical, reference, and research laboratories, as well as for industry, will be the translation of vast amounts of accrued NGS microbial data into convenient algorithm testing schemes for various applications (i.e., microbial identification, genotyping, and metagenomics and microbiome analyses) so that clinically relevant information can be reported to physicians in a format that is understood and actionable. These challenges will not be faced by clinical microbiologists alone but by every scientist involved in a domain where natural diversity of genes and gene sequences plays a critical role in disease, health, pathogenicity, epidemiology, and other aspects of life-forms. Overcoming these challenges will require global multidisciplinary efforts across fields that do not normally interact with the clinical arena to make vast amounts of sequencing data clinically interpretable and actionable at the bedside.

The Versatility of Opportunistic Infections Caused by Gemella Isolates Is Supported by the Carriage of Virulence Factors From Multiple Origins

The molecular basis of the pathogenesis of the opportunistic invasive infections caused by isolates of the Gemella genus remains largely unknown. Moreover, inconsistencies in the current species assignation were detected after genome-level comparison of 16 public Gemella isolates. A literature search detected that, between the two most pathogenic species, Gemella morbillorum causes about twice the number of cases compared to Gemella haemolysans. These two species shared their mean diseases - sepsis and endocarditis - but differed in causing other syndromes. A number of well-known virulence factors were harbored by all species, such as a manganese transport/adhesin sharing 83% identity from oral endocarditis-causing streptococci. Likewise, all Gemellae carried the genes required for incorporating phosphorylcholine into their cell walls and encoded some choline-binding proteins. In contrast, other proteins were species-specific, which may justify the known epidemiological differences. G. haemolysans, but not G. morbillorum, harbor a gene cluster potentially encoding a polysaccharidic capsule. Species-specific surface determinants also included Rib and MucBP repeats, hemoglobin-binding NEAT domains, peptidases of C5a complement factor and domains that recognize extracellular matrix molecules exposed in damaged heart valves, such as collagen and fibronectin. Surface virulence determinants were associated with several taxonomically dispersed opportunistic genera of the oral microbiota, such as Granulicatella, Parvimonas, and Streptococcus, suggesting the existence of a horizontally transferrable gene reservoir in the oral environment, likely facilitated by close proximity in biofilms and ultimately linked to endocarditis. The identification of the Gemella virulence pool should be implemented in whole genome-based protocols to rationally predict the pathogenic potential in ongoing clinical infections caused by these poorly known bacterial pathogens.

16S rRNA Gene Amplicon Based Metagenomic Signatures of Rhizobiome Community in Rice Field During Various Growth Stages

Rice is a major staple food across the globe. Its growth and productivity is highly dependent on the rhizobiome where crosstalk takes place between plant and the microbial community. Such interactions lead to selective enrichment of plant beneficial microbes which ultimately defines the crop health and productivity. In this study, rhizobiome modulation is documented throughout the development of rice plant. Based on 16S rRNA gene affiliation at genus level, abundance, and diversity of plant growth promoting bacteria increased during the growth stages. The observed α diversity and rhizobiome complexity increased significantly (p < 0.05) during plantation. PCoA indicates that different geographical locations shared similar rhizobiome diversity but exerted differential enrichment (p < 0.001). Diversity of enriched genera represented a sigmoid curve and subsequently declined after harvest. A major proportion of dominant enriched genera (p < 0.05, abundance > 0.1%), based on 16S rRNA gene, were plant growth promoting bacteria that produces siderophore, indole-3-acetic acid, aminocyclopropane-1-carboxylic acid, and antimicrobials. Hydrogenotrophic methanogens dominated throughout cultivation. Type I methanotrophs (n = 12) had higher diversity than type II methanotrophs (n = 6). However, the later had significantly higher abundance (p = 0.003). Strong enrichment pattern was also observed in type I methanotrophs being enriched during water logged stages. Ammonia oxidizing Archaea were several folds more abundant than ammonia oxidizing bacteria. K-strategists Nitrosospira and Nitrospira dominated ammonia and nitrite oxidizing bacteria, respectively. The study clarifies the modulation of rhizobiome according to the rice developmental stages, thereby opening up the possibilities of bio-fertilizer treatment based on each cultivation stages.

First bloodstream infection caused by Prevotella copri in a heart failure elderly patient with Prevotella-dominated gut microbiota: a case report

Background

Bloodstream infection (BSI) is a constant threat for hospitalized patients, and elderly patients are particularly susceptible to BSI caused by anaerobic bacteria. Changes in the gut microbiota composition may lead to pathogen overgrowth and translocation into the bloodstream. Consequently, domination of specific taxa in the intestinal bacterial community seems to be associated with a higher risk of bacteremia in some patient populations.

Case presentation

Here, we report the case of a 90-year-old heart failure (HF) patient who was admitted to the hospital for an acute state of cardiac decompensation. Twenty days after admission, he was febrile to 38.2 °C whereas his white blood count and C-reactive protein increased to 6190 cells/μL and 31.2 mg/L, respectively. Of the patient’s blood culture (BC) bottle pairs collected under the suspicion of infection, the anaerobic bottle yielded an organism that was later identified as Prevotella copri. Concomitantly, the patient’s fecal sample was obtained for the intestinal microbiota characterization by sequencing the V3/V4/V6 regions of the bacterial 16S rRNA gene. The analysis revealed highest relative abundances of Bacteroidales (34.1%), Prevotellaceae (19.0%), Prevotella (15.2%), and P. copri (6.1%) taxa, indicating that the patient’s gut microbiota was dominated by Prevotella organisms. The patient was successfully treated with metronidazole, and was discharged to a long-term care facility at 35 days of admission.

Conclusions

We provide the first evidence for a clinically significant BSI caused by P. copri and its relationship to a Prevotella-rich gut microbiota in the HF patient setting. When strengthening the pathogenicity of P. copri, the present case suggests that the gut may be a source of BSI caused by the rare anaerobic organism. Future studies are necessary to assess the role of the gut microbiota profiling for precise identification and targeted treatment of patients at high risk of BSI.

Clinical and microbiological features of bacteraemia with Gram-positive anaerobic cocci: a population-based retrospective study

OBJECTIVES

Gram-positive, anaerobic cocci (GPAC) can cause infections in humans. Only a few cases of bacteraemia with GPAC have been reported. We describe the clinical and microbiological characteristics of GPAC bacteraemia.

METHODS

A retrospective population-based study of GPAC bacteraemia 2012-2016 in southern Sweden was performed. GPAC were identified using matrix-associated laser desorption ionization time-of-flight mass spectrometry or 16S rRNA gene sequencing. Etests were used to determine antibiotic susceptibilities. Data on patient and infection characteristics, treatment, and outcome were collected from the medical records.

RESULTS

A total of 226 episodes of GPAC bacteraemia in adults were studied; this corresponds to an annual incidence of 3.4 cases per 100,000 persons per year. The bacteria identified were Anaerococcus spp. (n = 43), Atopobium spp. (n = 7), Blautia spp. (n = 1), Finegoldia spp. (n = 15), Parvimonas spp. (n = 100), Peptoniphilus spp. (n = 52), Peptostreptococcus spp. (n = 2), and Ruminococcus spp. (n = 9) of which 200 isolates were identified to the species level. Resistance to imipenem and piperacillin was not identified, whereas resistance among the 229 isolates to penicillin was detected in four, to metronidazole in six, and clindamycin in 16 isolates. The median age of patients was 73 years (55-83, IQR), 57% were male and comorbidities were common. Fifty-one per cent of infections were polymicrobial. In 60% of cases a focus of infection was identified. Forty per cent of patients had either organ dysfunction or shock. The 30-day mortality was 11%, and nosocomial infections were over-represented among the deceased.

CONCLUSIONS

GPAC bacteraemia is much more common than previously reported. GPAC-bacteraemia is a condition with significant mortality mainly affecting elderly persons with comorbidities.

Lactation Stage-Dependency of the Sow Milk Microbiota

Breast milk is essential for the initial development of neonatal animals, as it provides not only essential nutrients and a broad range of bioactive compounds but also commensal bacteria. The milk microbiota contributes to the "initial" intestinal microbiota of infants and also plays a crucial role in modulating and influencing neonatal health. However, the milk microbiota of sows has yet to be systematically investigated. The goal of the present study was to characterize variations in bacterial diversity and composition in sow milk over the duration of lactation using a high-throughput sequencing approach. Milk samples (n = 160) were collected from 20 healthy sows at eight different time points, and microbial profiles were analyzed by 16S ribosomal RNA (rRNA) sequencing using the Illumina MiSeq platform. The composition and diversity of the milk microbiota changed significantly in colostrum but was relatively stable in transitional and mature milk. Firmicutes and Proteobacteria were the most dominant phyla in sow milk. The relative abundances of the two most dominant bacterial genera, Corynebacterium and Streptococcus, were significantly higher in colostrum than in transitional milk and mature milk samples, and the other four most dominant bacterial taxa (Lactobacillus, two unclassified genera in the families Ruminococcaceae and Lachnospiraceae, and an unclassified genus in the order Clostridiales) demonstrated higher relative abundances in transitional and mature milk than in colostrum. Membrane transport, amino acid metabolism and carbohydrate metabolism were the most abundant functional categories in sow milk communities. Microbial network analysis based on the predominant genera revealed that the abundance of Helcococcus was negatively correlated with the abundances of most other genera in sow milk. Our results are the first to systematically indicate that the sow milk microbiota is a dynamic ecosystem in which changes mainly occur in the colostrum and remain generally stable throughout lactation.

Gram-Positive Uropathogens, Polymicrobial Urinary Tract Infection, and the Emerging Microbiota of the Urinary Tract

Gram-positive bacteria are a common cause of urinary-tract infection (UTI), particularly among individuals who are elderly, pregnant, or who have other risk factors for UTI. Here we review the epidemiology, virulence mechanisms, and host response to the most frequently isolated Gram-positive uropathogens: Staphylococcus saprophyticus, Enterococcus faecalis, and Streptococcus agalactiae. We also review several emerging, rare, misclassified, and otherwise underreported Gram-positive pathogens of the urinary tract including Aerococcus, Corynebacterium, Actinobaculum, and Gardnerella. The literature strongly suggests that urologic diseases involving Gram-positive bacteria may be easily overlooked due to limited culture-based assays typically utilized for urine in hospital microbiology laboratories. Some UTIs are polymicrobial in nature, often involving one or more Gram-positive bacteria. We herein review the risk factors and recent evidence for mechanisms of bacterial synergy in experimental models of polymicrobial UTI. Recent experimental data has demonstrated that, despite being cleared quickly from the bladder, some Gram-positive bacteria can impact pathogenic outcomes of co-infecting organisms. When taken together, the available evidence argues that Gram-positive bacteria are important uropathogens in their own right, but that some can be easily overlooked because they are missed by routine diagnostic methods. Finally, a growing body of evidence demonstrates that a surprising variety of fastidious Gram-positive bacteria may either reside in or be regularly exposed to the urinary tract and further suggests that their presence is widespread among women, as well as men. Experimental studies in this area are needed; however, there is a growing appreciation that the composition of bacteria found in the bladder could be a potentially important determinant in urologic disease, including susceptibility to UTI.

Peptoniphilus asaccharolyticus-associated septic arthritis and osteomyelitis in a woman with osteoarthritis and diabetes mellitus

Peptoniphilus asaccharolyticus, a Gram-positive obligatory anaerobic coccus, is a commensal of the human vagina and gut and can be an opportunistic pathogen in immunocompromised patients. It is usually part of polymicrobial anaerobic infections such as skin and soft tissue infections in diabetics, bone and joint infections and surgical site infections; however, infections caused by P. asaccharolyticus in pure culture have been reported as well. Herein, we describe a case of septic arthritis and osteomyelitis caused by P. asaccharolyticus in a woman with osteoarthritis and diabetes mellitus.

16S rRNA deep sequencing identifies Actinotignum schaalii as the major component of a polymicrobial intra-abdominal infection and implicates a urinary source

Introduction. It can be difficult to catalogue the individual organisms comprising polymicrobial patient infections, both because conventional clinical microbiological culture does not facilitate the isolation and enumeration of all members of a complex microbial community, and because fastidious organisms may be mixed with organisms that grow rapidly in vitro. Empiric antimicrobial treatment is frequently employed based on the anatomical site and the suspected source of the infection, especially when an appropriately collected surgical specimen is not obtained.

Case presentation. We present a case of an intra-abdominal infection in a patient with complex anatomy and recurrent urinary tract infections. Imaging did not reveal a clear source of infection, no growth was obtained from urine cultures and initial abdominal fluid cultures were also negative. In contrast, 16S rRNA deep sequencing of abdominal fluid samples revealed mixed bacterial populations with abundant anaerobes, including Actinotignum schaalii (Actinobaculum schaalii). Ultimately, only Enterobacter cloacae complex and meticillin-resistant Staphylococcus aureus, both of which were identified by sequencing, were recovered by culture.

Conclusion. The clinical application of 16S rRNA deep sequencing can more comprehensively and accurately define the organisms present in an individual patient's polymicrobial infection than conventional microbiological culture, detecting species that are not recovered under standard culture conditions or that are otherwise unexpected. These results can facilitate effective antimicrobial stewardship and help elucidate the possible origins of infections.

Impacts of canine distemper virus infection on the giant panda population from the perspective of gut microbiota

The recent increase in infectious disease outbreaks has been directly linked to the global loss of biodiversity and the decline of some endangered species populations. Between December 2014 and March 2015, five captive giant pandas died due to canine distemper virus (CDV) infection in China. CDV has taken a heavy toll on tigers and lions in recent years. Here, we describe the first gut microbiome diversity study of CDV-infected pandas. By investigating the influence of CDV infection on gut bacterial communities in infected and uninfected individuals and throughout the course of infection, we found that CDV infection distorted the gut microbiota composition by reducing the prevalence of the dominant genera, Escherichia and Clostridium, and increasing microbial diversity. Our results highlight that increases in intestinal inflammation and changes in the relative abundances of pathogen-containing gut communities occur when individuals become infected with CDV. These results may provide new insights into therapeutics that target the microbiota to attenuate the progression of CDV disease and to reduce the risk of gut-linked disease in individuals with CDV. In addition, our findings underscore the need for better information concerning the dynamics of infection and the damage caused by pathogens in panda populations.