Objectives and Study

Modulating the developing gut microbiome in young infants may improve gut health, nutrition and growth. We assessed whether dietary supplementation with pro- or synbiotics to newborns in rural Kenya exposed to poor sanitation and hygiene and at risk of growth faltering, would improve gut health and reduce systemic inflammation.

Methods

We conducted an open-label, randomized, 4-arm controlled trial. Newborns less than four days old were enrolled at the Homa Bay County Teaching and Referral Hospital, western Kenya. They were randomly allocated, stratified by HIV exposure, in a 1:1:1:1 ratio to one of 4 study arms to receive either Labinic synbiotic, Lab4b synbiotic, Lab4b probiotic or no supplement, given daily for ten days and then weekly until six months of age. Biomarkers of systemic inflammation (plasma a-1-acid glycoprotein (AGP), a biomarker of longer-term systemic inflammation; primary outcome), gut health and growth (secondary outcomes) were measured in blood and stool samples collected at 6 weeks, 3, and 6 months.

Results

600 newborns were enrolled between 28th October, 2020 and 13th January, 2022. Baseline demographic, clinical, socio-economic and hygiene/sanitation variables were similar in the four study arms.

Median plasma AGP concentration, increased progressively at 3 and 6 months among the controls but this was almost completely abrogated in each of the intervention arms (Figure). At 6 months, plasma AGP was raised (>1g/L) in 56/134 (41.8%) infants in the control arm but in <1.5% infants in each of the intervention arms (P<0.001). Gut health biomarkers were significantly higher at 3 and/or 6 months in the control arm than in any intervention arm (P<0.001). Growth hormones were slightly, but significantly, lower at 6 months in the control arm than in any intervention arm.

Conclusions

In a low-resource setting, pro/synbiotics offer a novel approach to improving gut health and reducing systemic inflammation in young infants.

Objectives and Study

Necrotizing enterocolitis is a devastating gastrointestinal disease that typically afflicts premature infants. Understanding its pathogenesis may improve its treatment and prevention.

Human intestinal enteroids are a novel and clinically relevant model to study NEC in vitro. The aim of this research is to assess the differences observed in the phenotype, function, and gene expression of organoids derived from NEC versus NON-NEC infants.

Methods

Discarded intestinal segments from infants undergoing surgical resection for NEC and for intestinal malformations (controls) were collected. Stem cells derived specimens were isolated and seeded in Matrigel domes and grown for 7 days in culture. Spheres were trypsinized into a single-cell state and seeded onto membrane transwell to create 2D monolayers. The culture medium was changed every other day until the cultures reached confluence, as determined by TEER (trans-epithelial electrical resistance) monitoring and microscopic observation.

Paracellular permeability was assessed using TEER values and through the measurements of paracellular marker FITC-dextran 4000 (a fluorescently labelled sugar molecule of 4 kDa) passage. Cytotoxicity was measured through LDH test. RNA was extracted from monolayers and then converted to cDNA. Gene expression quantitation was performed with real-time PCR detection system for gene expression analysis.

Results

Cells from NEC and control grew and matured at different velocities, NEC monolayers being significantly slower. Monolayers derived from NEC patients showed phenotypic differences versus healthy controls (figure 1). TEER measurements in NEC monolayers were significantly lower and permeability and cytotoxicity parameters were significantly higher in NEC monolayers (figure 2 and 3). qPCR gene expression confirmed the increased expression of TLR4 and genes involved in inflammation and necroptosis in NEC samples and reduced expression of genes involved in barrier function (Figure 4).

Conclusions

Our findings indicate that organoids derived from NEC patients are a reliable model to study NEC pathophysiology and may represent a valid tool to target therapeutic treatment interventions.

Objectives and Study

Late onset Neonatal sepsis (LONS) is a leading cause of mortality in preterm infants, affecting up to 15% of preterm neonates and a mortality rate of ~15%. Clinical symptoms of LONS are nonspecific and diagnosis is often established in an advanced stage of infection, illustrating the need for novel preclinical biomarkers. This study aimed to identify predictive biomarkers for LONS in preterm infants using fecal metagenomics and targeted metabolomics.

Methods

In a Dutch multicentric study, fecal samples and clinical data were collected daily from birth to onset of S. aureus and E. coli LONS in preterm neonates and matched to healthy controls by gestational and postnatal age, antibiotic exposure and birthcenter (n=40). 16S sequencing, shotgun metagenomics and quantitative tryptophan (Trp) metabolomics was performed up to 7 days before and 5 days after LONS diagnosis. Functional differences were evaluated by pan-genome and Trp metabolite analysis. Predictive value of 16S was assessed by classification modeling. In vitro aryl hydrocarbon receptor (AhR) activity was measured by reporter assay.

Results

Relative abundance (RA) of fecal E.coli was significantly higher pre-onset in E.coli LONS, compared to matched controls. In contrast, no significant difference in RA of fecal S.aureus was detected in S.aureus LONS. Fecal Trp metabolites detected included kynurenine, serotonin and Indole-lactic-acid. Indole-x was significantly elevated 5 days pre-diagnosis of E.coli LONS(p=0.04) and activated AhR in reporter assay at measured concentrations. In support, metagenomics analysis indicated a negative association to microbial Trp biosynthesis in the E.coli LONS metagenome pre-diagnosis, suggesting higher dependence on exogenous Trp.

Conclusions

This multi-omics approach indicates, in line with previous findings, a strong increase in relative abundance of E.coli, but not S.aureus prior to LONS onset, and a functional difference mediated by Trp metabolism and indole-x, indicating relevance as novel preclinical biomarker and affected host-microbe interaction in the neonatal gut pre-LONS.

Objectives and Study

SARS-CoV-2 is a virus with enteric tropism, and diarrhea is a frequent clinical presentation of pediatric COVID-19. Aims of this study was to investigate the prevalence of SARS-CoV-2-associated acute diarrhea among children hospitalized for acute COVID-19 and to compare their clinical and laboratory features with pediatric AGE with a different infectious aetiology.

Methods

Hospitalized children with laboratory-confirmed SARS-CoV-2 infection were enrolled in the study. The prevalence of COVID-19-associated AGE was defined by the presence of diarrhea (3 or more loose stools/day). Clinical and laboratory features were compared with a historical cohort of children with a diagnosis of AGE hospitalized before COVID-19 pandemics.

Results

Among 407 hospitalized children with COVID-19, 76 (18.7%) had diarrhea. The historical cohort of AGE included 109 patients. Children with COVID-19-associated AGE did not differ from the historical AGE group in terms of sex, age and comorbidities. Compared to children with COVID-19, children of historical cohort had more frequently fever (45.9% vs 26.3%, p=0.009), vomiting (52.3% vs 31.6%, p=0.007), dehydration (51.4% vs 15.8%, p<0.001) and need for parenteral rehydration (78% vs 39.5%, p<0.001). COVID-19 patients presented higher incidence of respiratory symptoms (22.4% vs 5.5%, p=0.001) and tended to present more frequently with abdominal pain (27.6% vs 17.4%, p=0.09) and poor feeding (17.1% vs 11%, p=0.28). C-reactive protein and white blood cells were similar in both groups, although procalcitonin tended to be higher in COVID-19 (2.8±7.4 vs 0.9±1.9 ng/mL, p=0.09).

Conclusions

Acute diarrhea is common in COVID-19 and SARS-CoV-2 infection should be suspected in children with a clinical presentation of AGE, especially when diarrhea is associated with respiratory symptoms. In children with SARS-CoV-2-associated diarrhea the clinical severity including vomiting and the degree of dehydration are reduced and the need for fluid supplementation is less frequent than other intestinal infections.

Objectives and Study

Autoimmune gastritis (AIG) is a chronic inflammatory disorder characterized by progressive mucosal atrophy. There is limited data on the natural history of AIG in children. We aimed to characterize the clinical features and outcomes of pediatric patients with AIG and assess the role of H. pylori infection in this disorder.

Methods

This was a multi-center retrospective study that included pediatric patients diagnosed with AIG between 1/1/2000-31/12/2021, based on the demonstration of histological corpus-predominant atrophic gastritis, with or without positive anti-parietal cell antibodies (APCA) or anti-intrinsic factor (IF) antibodies. Demographic, clinical, laboratory, endoscopic, and histologic data were retrieved at different timepoints.

Results

Thirty-two patients, (23 females, [72%], median age 12.5 [IQR 7-15] years at diagnosis) were included. Twenty-one patients (66%) had positive APCA or anti-IF serology. The most common presenting manifestations were iron deficiency anemia (74%), poor growth (35%), and abdominal pain (32%). Mean hemoglobin level at diagnosis was 9.3±2.9 g/dL, and 23/27(85%) demonstrated increased serum gastrin levels (median 508, IQR 214-916). Accompanying autoimmune disorders were significantly more common in patients with positive APCA/anti-IF serology (62% vs. 18%, P<0.05), with autoimmune thyroiditis and insulin-dependent diabetes being the most common. Pseudopyloric or intestinal-type metaplasia was present at diagnosis in 7 (23%) patients. H. pylori was identified in a single patient, while two patients had prior H. pylori eradication. At a median follow-up of 25.5 (IQR 16-46) months, four patients without metaplasia at diagnosis developed metaplasia and one patient developed a type 1 gastric neuroendocrine tumor. Importantly, endoscopic improvement wasn't identified in any patients.

Conclusions

This is the largest cohort of children with AIG, to date. A diagnosis of AIG should be considered in iron-deficiency anemia, especially in patients with autoimmune features. Endoscopic follow-up is required, given the risk of intestinal metaplasia and development of gastric neuroendocrine tumors.

Objectives and Study

Acute Severe Colitis (ASC) is a frequent and severe complication of ulcerative colitis (UC) that can occur at any time during the disease. Its prognosis can be severe with a high risk of colectomy. The use of immunosuppressants and more recently biotherapies seem to reduce the risk of colectomy. We wished to study the long-term evolution of pediatric-onset UC patients after ASC.

Methods

This retrospective study was conducted in 12 centers of the GETAID pediatric in France. Data on patients with UC aged < 18 years admitted with ASC (defined as pediatric ulcerative colitis activity index [PUCAI] score ≥ 65) between January 2010 and January 2021 were collected at discharge and at 1, 3 and 5 years after admission. The primary outcome of our study was colectomy-free rates at each time points. A univariate analysis comparing the profile at diagnosis and at ASC of patients who underwent colectomy, and the others was performed to look for prognostic factors associated with the risk of surgery.

Results

Of the 102 patients admitted with ASC, 95 [93%] were treated with corticosteroids. Forty-six [48%] patients were escalated to second-line therapy, mainly to infliximab. Nine patients [8.8%] underwent colectomy before discharge. Long-term follow-up showed colectomy-free rates were 83%, 76% and 72% at 1, 3 and 5 years after initial ASC admission, respectively. In a multivariate analysis, active disease, and use of methotrexate were significantly associated with colectomy risk. A short delay between diagnosis and ASC, rapid steroid use for ASC and second line therapy with azathioprine and Infliximab were significantly associated with a lower risk of colectomy.

Conclusions

The rate of colostomy remains high after an episode of acute colitis despite the earlier use of biotherapies. But long-term outcome of pediatric-onset UC patients is good with sustained clinical and biological remission.