Dynamics of the bacterial gut microbiota in preterm and term infants after intravenous amoxicillin/ceftazidime treatment

BACKGROUND: It is important to understand the consequences of pre-emptive antibiotic treatment in neonates, as disturbances in microbiota development during this key developmental time window might affect early and later life health outcomes. Despite increasing knowledge regarding the detrimental effect of antibiotics on the gut microbiota, limited research focussed on antibiotic treatment duration. We determined the effect of short and long amoxicillin/ceftazidime administration on gut microbiota development during the immediate postnatal life of preterm and term infants. METHODS: Faeces was collected from 63 (pre) term infants at postnatal weeks one, two, three, four and six. Infants received either no (control), short-term (ST) or long-term (LT) postpartum amoxicillin/ceftazidime treatment. RESULTS: Compared to control infants, ST and LT infants' microbiota contained significantly higher abundance of Enterococcus during the first two postnatal weeks at the expense of Bifidobacterium and Streptococcus. Short and long antibiotic treatment both allowed for microbiota restoration within the first six postnatal weeks. However, Enterococcus and Bifidobacterium abundances were affected in fewer ST than LT infants. CONCLUSIONS: Intravenous amoxicillin/ceftazidime administration affects intestinal microbiota composition by decreasing the relative abundance of Escherichia-Shigella and Streptococcus, while increasing the relative abundance of Enterococcus and Lactobacillus species during the first two postnatal weeks. Thriving of enterococci at the expense of bifidobacteria and streptococci should be considered as aspect of the cost-benefit determination for antibiotic prescription.</p

Diagnostic test strategies in children at increased risk of inflammatory bowel disease in primary care

In children with symptoms suggestive of inflammatory bowel disease (IBD) who present in primary care, the optimal test strategy for identifying those who require specialist care is unclear. We evaluated the following three test strategies to determine which was optimal for referring children with suspected IBD to specialist care: 1) alarm symptoms alone, 2) alarm symptoms plus c-reactive protein, and 3) alarm symptoms plus fecal calprotectin.A prospective cohort study was conducted, including children with chronic gastrointestinal symptoms referred to pediatric gastroenterology. Outcome was defined as IBD confirmed by endoscopy, or IBD ruled out by either endoscopy or unremarkable clinical 12 month follow-up with no indication for endoscopy. Test strategy probabilities were generated by logistic regression analyses and compared by area under the receiver operating characteristic curves (AUC) and decision curves.We included 90 children, of whom 17 (19%) had IBD (n = 65 from primary care physicians, n = 25 from general pediatricians). Adding fecal calprotectin to alarm symptoms increased the AUC significantly from 0.80 (0.67-0.92) to 0.97 (0.93-1.00), but adding c-reactive protein to alarm symptoms did not increase the AUC significantly (p > 0.05). Decision curves confirmed these patterns, showing that alarm symptoms combined with fecal calprotectin produced the diagnostic test strategy with the highest net benefit at reasonable threshold probabilities.In primary care, when children are identified as being at high risk for IBD, adding fecal calprotectin testing to alarm symptoms was the optimal strategy for improving risk stratification

Evaluation of exclusive enteral nutrition and corticosteroid induction treatment in new-onset moderate-to-severe luminal paediatric Crohn's disease

To induce remission in luminal paediatric Crohn's disease (CD), the ESPGHAN/ECCO guideline recommends treatment with exclusive enteral nutrition (EEN) or oral corticosteroids. In newly diagnosed moderate-to-severe paediatric CD patients, we determined the proportion of patients in which EEN or corticosteroids induced remission and maintained remission on azathioprine monotherapy. We included patients from the "TISKids" study assigned to the conventional treatment arm. Patients were aged 3-17 years and had new-onset, untreated luminal CD with weighted paediatric CD activity index (wPCDAI)> 40. Induction treatment consisted of EEN or oral corticosteroids; all received azathioprine maintenance treatment from start of treatment. The primary outcome of this study was endoscopic remission defined as a SES-CD score Conclusion: In children with moderate-to-severe newly diagnosed CD, induction treatment with EEN or CS regularly is insufficient to achieve endoscopic remission without treatment escalation at week 10.Peer reviewe

Exome sequencing in patient-parent trios suggests new candidate genes for early-onset primary sclerosing cholangitis

BACKGROUND & AIMS Primary sclerosing cholangitis (PSC) is a rare bile duct disease strongly associated with inflammatory bowel disease (IBD). Whole-exome sequencing (WES) has contributed to understanding the molecular basis of very early-onset IBD, but rare protein-altering genetic variants have not been identified for early-onset PSC. We performed WES in patients diagnosed with PSC METHODS In this multicentre study, WES was performed on 87 DNA samples from 29 patient-parent trios with early-onset PSC. We selected rare (minor allele frequency <2%) coding and splice-site variants that matched recessive (homozygous and compound heterozygous variants) and dominant (de novo) inheritance in the index patients. Variant pathogenicity was predicted by an in-house developed algorithm (GAVIN), and PSC-relevant variants were selected using gene expression data and gene function. RESULTS In 22 of 29 trios we identified at least 1 possibly pathogenic variant. We prioritized 36 genes, harbouring a total of 54 variants with predicted pathogenic effects. In 18 genes, we identified 36 compound heterozygous variants, whereas in the other 18 genes we identified 18 de novo variants. Twelve of 36 candidate risk genes are known to play a role in transmembrane transport, adaptive and innate immunity, and epithelial barrier function. CONCLUSIONS The 36 candidate genes for early-onset PSC need further verification in other patient cohorts and evaluation of gene function before a causal role can be attributed to its variants.Peer reviewe

Pediatric Crohn's disease activity at diagnosis, its influence on pediatrician's prescribing behavior, and clinical outcome 5 years later

Background: No studies have been performed in which therapeutic regimens have been compared between mild and moderate-to-severe pediatric Crohn's disease (CD) at diagnosis. The aim was to analyze pediatric CD activity at diagnosis, its influence on pediatrician's prescribing behavior, and clinical Outcome 5 years later. Methods: In a retrospective multicenter Study we divided pediatric CD patients at diagnosis into mild or moderate-severe disease. We compared initial therapies. duration of first remission, number of exacerbations, height-for-age and weight-for-height evolvement, and cumulative duration of systemic steroid use in a 5-year follow-up period. Results: Forty-three children were included (25 with mild and 18 with moderate-severe disease). Aminosalicylate monotherapy was more frequently prescribed in the Mild group (40% versus 17% P <0.01). The median duration of systemic steroid use was 18.3 months in the mild group and 10.4 months in the moderate-severe group (P = 0.09). Duration of first remission was 15.0 months in the mild group and 23.4 months in the moderate-severe group (P = 0.16). The mean number of exacerbations was 2.2 in the mild group and 1.8 in the moderate-severe group (P = 0.28). Conclusions: CD patients with mild disease were treated with aminosalicylate monotherapy more frequently. These patients, however, tend to have more exacerbations, shorter duration of first remission, and longer total duration of systemic steroid use. Our data support the concept that severity of disease at diagnosis does not reliably predict subsequent clinical course. This study suggests that there is no indication that children with mild CD should be treated differently compared to children with moderate-severe disease

Microbiota development in preterm and term infants

Microbiota development in (pre)term infants receiving various durations of postpartum antibiotic treatment. Determined through 16S rRNA gene amplicon sequencing (MiSeq, Illumina)

Microbiota development in preterm and term infants

Microbiota development in (pre)term infants receiving various durations of postpartum antibiotic treatment. Determined through 16S rRNA gene amplicon sequencing (MiSeq, Illumina)

Early life intestinal microbiota development in late preterm infants and the effect of antibiotics.

To study the effect of the duration of antibiotic treatment on intestinal microbiota development during the first six postnatal weeks in late-preterm infants through 454 pyrosequencing of the 16S rRNA gene. Total of 96 samples