Profiling the Urobiota in a Pediatric Population with Neurogenic Bladder Secondary to Spinal Dysraphism.

The human bladder has been long thought to be sterile until that, only in the last decade, advances in molecular biology have shown that the human urinary tract is populated with microorganisms. The relationship between the urobiota and the development of urinary tract disorders is now of great interest. Patients with spina bifida (SB) can be born with (or develop over time) neurological deficits due to damaged nerves that originate in the lower part of the spinal cord, including the neurogenic bladder. This condition represents a predisposing factor for urinary tract infections so that the most frequently used approach to treat patients with neurogenic bladder is based on clean intermittent catheterization (CIC). In this study, we analyzed the urobiota composition in a pediatric cohort of patients with SB compared to healthy controls, as well as the urobiota characteristics based on whether patients received CIC or not.

Evaluation of Everolimus Activity against Mycobacterium tuberculosis Using In Vitro Models of Infection.

Even though Everolimus has been investigated in a phase II randomized trial as a host-directed therapy (HDT) to treat tuberculosis (TB), an oncological patient treated with Everolimus for a neuroendocrine pancreatic neoplasia developed active TB twice and a non-tuberculous mycobacterial (NTM) infection in a year and a half time span. To investigate this interesting case, we isolated and genotypically characterized the Mycobacterium tuberculosis (Mtb) clinical strain from the patient and tested the effect of Everolimus on its viability in an axenic culture and in a peripheral blood mononuclear cell (PBMCs) infection model. To exclude strain-specific resistance, we tested the activity of Everolimus against Mtb strains of ancient and modern lineages. Furthermore, we investigated the Everolimus effect on ROS production and autophagy modulation during Mtb infection. Everolimus did not have a direct effect on mycobacteria viability and a negligible effect during Mtb infection in host cells, although it stimulated autophagy and ROS production. Despite being a biologically plausible HDT against TB, Everolimus does not exert a direct or indirect activity on Mtb. This case underlines the need for a careful approach to drug repurposing and implementation and the importance of pre-clinical experimental studies.

Celiac Disease Predisposition and Genital Tract Microbiota in Women Affected by Recurrent Pregnancy Loss.

The incidence of Idiopathic Recurrent Pregnancy Loss (RPL) is doubled in patients suffering from Celiac Disease (CD) compared to healthy populations. CD genetic components are HLA class II genes known as HLA-DQ2 and DQ8. Genetically susceptible women can remain asymptomatic even though they are exposed to a doubled risk of RPL compared to the general population. Furthermore, CD has been associated with microbiota alterations. The aim of this study is to evaluate endometrial and vaginal microbiota in HLA-DQ2/DQ8 positive and negative RPL patients compared to healthy pregnant women. Endometrial and vaginal microbiota of 3 subgroups were evaluated: 15 HLA-DQ2/DQ8 positive RPL women, 25 HLA DQ2/DQ8 negative RPL women (for a total of 40 RPL women) and 7 healthy fertile controls with previous uncomplicated pregnancies (all HLA-DQ2/DQ8 negative). The 2 RPL subgroups (HLA-DQ2/DQ8 positive and negative) showed a different endometrial and vaginal composition in the Lactobacillacae family compared to controls: Lactobacillus acidophilus was absent both in the vaginal and endometrial samples of RPL women, while Lactobaciluus iners, which can favor a less stable vaginal microbiota, was found only in RPL women (26.4% in HLA DQ2/DQ8 positive and 22.1% HLA DQ2/DQ8 negative) in both the vaginal and endometrial districts. In conclusion, both HLA DQ2/DQ8 positive-RPL and HLA DQ2/DQ8 negative-RPL women showed different endometrial and vaginal microbiota composition compared to healthy controls.

The Relationship Between Maternal and Neonatal Microbiota in Spontaneous Preterm Birth: A Pilot Study.

The newborn's microbiota composition at birth seems to be influenced by maternal microbiota. Maternal vaginal microbiota can be a determining factor of spontaneous Preterm Birth (SPPTB), the leading cause of perinatal mortality. The aim of the study is to investigate the likelihood of a causal relationship between the maternal vaginal microbiota composition and neonatal lung and intestinal microbiota profile at birth, in cases of SPPTB. The association between the lung and/or meconium microbiota with the subsequent development of bronchopulmonary dysplasia (BPD) was also investigated. Maternal vaginal swabs, newborns' bronchoalveolar lavage fluid (BALF) (1st, 3rd, 7th day of life) and first meconium samples were collected from 20 women and 23 preterm newborns with gestational age ≤ 30 weeks (12 = SPPTB; 11 = Medically Indicated Preterm Birth-MIPTB). All the samples were analyzed for culture examination and for microbiota profiling using metagenomic analysis based on the Next Generation Sequencing (NGS) technique of the bacterial 16S rRNA gene amplicons. No significant differences in alpha e beta diversity were found between the neonatal BALF samples of SPPTB group and the MIPTB group. The vaginal microbiota of mothers with SPPTB showed a significant difference in alpha diversity with a decrease in Lactobacillus and an increase in Proteobacteria abundance. No association was found between BALF and meconium microbiota with the development of BPD. Vaginal colonization by Ureaplasma bacteria was associated with increased risk of both SPPTB and newborns' BPD occurrence. In conclusion, an increase in α-diversity values and a consequent fall in Lactobacillus in vaginal environment could be associated to a higher risk of SPPTB. We could identify neither a specific neonatal lung or meconium microbiota profiles in preterm infants born by SPPTB nor a microbiota at birth suggestive of subsequent BPD development. Although a strict match has not been revealed between microbiota of SPPTB mother-infant couples, a relationship cannot be excluded. To figure out the reciprocal influence of the maternal-neonatal microbiota and its potential role in the pathogenesis of SPPTB and BPD further research is needed.

The Dark Side of the COVID-19 Treatments on Mycobacterium Tuberculosis Infection.

Since the emergence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) at the end of 2019, a number of medications have been used to treat the infection and the related Coronavirus disease - 19 (COVID-19). Some of the administered drugs were tested or used in practice only on the basis of biological plausibility; a promising strategy was to target the host immune response, with host directed therapies (HDTs), to reduce systemic hyperinflammation and hypercytokinemia responsible for additional tissue damage. We summarize the treatments against SARS-CoV-2 and underline their possible effects on Mycobacterium tuberculosis (Mtb) infection. Both SARS-CoV-2 and Mtb respiratory infections impair the host's immune response. Furthermore, little research has been conducted on the impact of medicaments used to counteract COVID-19 disease in patients with Latent Tuberculosis Infection (LTBI). A number of these drugs may modulate host immune response by modifying LTBI dynamic equilibrium, favoring either the host or the bacteria.

Comparative Fecal Microbiota Analysis of Infants With Acute Bronchiolitis Caused or Not Caused by Respiratory Syncytial Virus.

Bronchiolitis due to respiratory syncytial virus (RSV) or non-RSV agents is a health-menacing lower respiratory tract (LRT) disease of infants. Whereas RSV causes more severe disease than other viral agents may, genus-dominant fecal microbiota profiles have been identified in US hospitalized infants with bronchiolitis. We investigated the fecal microbiota composition of infants admitted to an Italian hospital with acute RSV (25/37 [67.6%]; group I) or non-RSV (12/37 [32.4%]; group II) bronchiolitis, and the relationship of fecal microbiota characteristics with the clinical characteristics of infants. Group I and group II infants differed significantly (24/25 [96.0%] versus 5/12 [41.7%]; P = 0.001) regarding 90% oxygen saturation (SpO2), which is an increased respiratory effort hallmark. Accordingly, impaired feeding in infants from group I was significantly more frequent than in infants from group II (19/25 [76.0%] versus 4/12 [33.3%]; P = 0.04). Conversely, the median (IQR) length of stay was not significantly different between the two groups (seven [3-14] for group I versus five [5-10] for group II; P = 0.11). The 16S ribosomal RNA V3-V4 region amplification of infants' fecal samples resulted in 299 annotated amplicon sequence variants. Based on alpha- and beta-diversity microbiota downstream analyses, group I and group II infants had similar bacterial communities in their samples. Additionally, comparing infants having <90% SpO2 (n = 29) with infants having ≥90% SpO2 (n = 8) showed that well-known dominant genera (Bacteroides, Bifidobacterium, Escherichia/Shigella, and Enterobacter/Veillonella) were differently, but not significantly (P = 0.44, P = 0.71, P = 0.98, and P = 0.41, respectively) abundant between the two subgroups. Overall, we showed that, regardless of RSV or non-RSV bronchiolitis etiology, no fecal microbiota-composing bacteria could be associated with the severity of acute bronchiolitis in infants. Larger and longitudinally conducted studies will be necessary to confirm these findings.

Improved gut microbiota features after the resolution of SARS­CoV­2 infection.

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) has a tropism for the gastrointestinal tract and several studies have shown an alteration of the gut microbiota in hospitalized infected patients. However, long-term data on microbiota changes after recovery are lacking. METHODS: We enrolled 30 patients hospitalized for SARS­CoV­2-related pneumonia. Their gut microbiota was analyzed within 48 h from the admission and compared with (1) that of other patients admitted for suspected bacterial pneumonia (control group) (2) that obtained from the same subject 6 months after nasopharyngeal swab negativization. RESULTS: Gut microbiota alpha-diversity increased 6 months after the resolution of SARS-CoV-2 infection. Bacteroidetes relative abundance was higher (≈ 36.8%) in patients with SARS-CoV-2, and declined to 18.7% when SARS-CoV-2 infection resolved (p = 0.004). Conversely, Firmicutes were prevalent (≈ 75%) in controls and in samples collected after SARS-CoV-2 infection resolution (p = 0.001). Ruminococcaceae, Lachnospiraceae and Blautia increased after SARS-CoV-2 infection resolution, rebalancing the gut microbiota composition. CONCLUSION: SARS-CoV-2 infection is associated with changes in the gut microbiome, which tend to be reversed in long-term period.

Characterization of gut microbiota in patients with metabolic syndrome candidates for bariatric/metabolic surgery: Preliminary findings of a multi-center prospective study.

INTRODUCTION: gut microbiota (GM) seems to be involved in the pathophysiology and progression of both metabolic syndrome (MS) and obesity. The aim was to investigate GM's composition in patients with severe obesity, candidates for bariatric/metabolic surgery BMS. MATERIALS AND METHODS: Multicentre, prospective, cohort study, enrolling 84 patients with BMI 40-55 kg/m2, divided bymetabolic status (MS) inhealthy(group A), pre-MS (B), or MS (C). RESULTS: No differences were foundregarding anthropometric,nutritional parameters, except for vitamin D.As a whole the alpha and beta diversity examinations showed no statistical differences in GM profile. A total of 5/7 phyla with relative frequencies were identified above 0.1% (Actinobacteria,Bacteroidetes,Firmicutes,Proteobacteria,Verrucomicrobia).FusobacteriaandPatescibacteriarepresented the less abundant. There were no significant differences in the top ten genera.Data onBacteroidetes(inversely related to triglycerides and LDL and directly related to HDL levels) and onFirmicutes(opposite trend) relative abundances suggest no differences among the three conditions.No correlation between the relative abundance of themain phylaand plasmatic glucose levels was observed. CONCLUSIONS: In a selected cohort of patients with obesity, MS did not affect the preoperative GM's profile. Severe obesity, per se, seems to be an independent condition affecting GM.

First description of the katG gene deletion in a Mycobacterium tuberculosis clinical isolate and its impact on the mycobacterial fitness.

Isoniazid (INH) is the cornerstone of the anti-tuberculosis regimens and emergence of Mycobacterium tuberculosis (Mtb) resistant strains is a major threat to our ability to control tuberculosis (TB) at global level. Mutations in the gene coding the catalase KatG confer resistance to high level of INH. In this paper, we describe for the first time a complete deletion of the genomic region containing the katG gene in an Mtb clinical strain isolated in Italy in a patient with HIV infection that previously completed INH preventive therapy. We genotypically characterized the Mtb strain and showed that katG deletion confers high-level resistance to INH (MIC > 25.6 µg/mL). The katG deletion did not impact significantly on Mtb fitness as we did not detect enhanced susceptibility to H2O2 compared to the wild type Mtb strains nor impaired growth in in vitro infection models. These findings highlight the ability of Mtb to acquire resistance to INH while maintaining fitness and pathogenic potential.