Pediatric Enterococcal Bacteremia: A 12-Year Retrospective Study in a French Pediatric Center

BACKGROUND

Enterococcal bloodstream infections (EBSIs) are rare infections in children associated with 5%-10% of mortality in previous studies. The recent evolution of antimicrobial resistance and therapies require updated data.

METHODS

We conducted an observational retrospective study between January 2008 and December 2019 describing the characteristics of children with EBSI in a French pediatric hospital. All positive Enterococcus spp. blood cultures associated with sepsis symptoms were analyzed. We also compared characteristics of healthcare-associated infections (HAIs) and community-acquired infections (CAIs) and described antimicrobial resistance evolution during this period.

RESULTS

In total 74 EBSI were included. Enterococcus faecalis was the most common pathogen (n = 60/74, 81%) followed by Enterococcus faecium (n = 18, 24%), including 4 enterococcal coinfections. EBSIs were mainly associated with central-line associated infection (38%), surgical site infection (14%) or urinary tract infection (11%). An underlying disease was present in 95.9%. However, 4 patients died in the month following the EBSI resulting in a 5.4%, 30-day mortality. All were HAI. HAI (84% of EBSI) was associated with longer bacteremia [31% persistent bacteremia (more than 3 days) versus 0% for CAI; P = 0.029] and more antimicrobial resistance. Amoxicillin resistance is increasing since 2013 in E. faecium (63% in 2013-2019), although high-level gentamicin resistance is stable (19%). Only 1 EBSI due to vancomycin-resistant Enterococcus was described in our cohort, who died.

CONCLUSIONS

EBSIs are rare infections in children mostly described in children with underlying disease. Healthcare-associated bacteremia is associated with higher rates of resistance and poorer prognosis, requiring the involvement of pediatric infectious disease specialists to improve management.

Shigella-associated mild encephalitis with reversible splenial lesion in Hospital Center Delafontaine, Saint-Denis, France: a case report

BACKGROUND

Mild encephalitis with reversible splenial lesion of the corpus callosum (MERS) is a clinical/radiological syndrome characterized by hyperintense signal changes in the splenium of the corpus callosum visible on diffusion weighted imaging (DWI) in the brain Magnetic Resonance Imaging (MRI) associated with various neurological symptoms. Progression is usually favorable with disappearance of the MRI brain lesion and regression of clinical symptoms over a few days to a few weeks. The exact pathophysiology remains unclear. MERS can be associated with various pathogens.

CASE PRESENTATION

We report here a paediatric case of MERS associated with Shigella flexneri infection. A five-year-old boy with no relevant past medical history presented with symptoms such as headache, fever, profuse diarrhea and hallucinations. A brain Magnetic Resonance Imaging performed on Day 2 of the symptoms revealed hyperintense signal changes of the splenium of the corpus callosum in T2 FLAIR sequence. This infection had a favorable outcome after antibiotic therapy. No further recurrence of symptoms was observed and a follow-up clinical examination eight weeks later was normal. A follow-up brain Magnetic Resonance Imaging three months after discharge was also normal and the hyperintense signal changes of the splenium of the corpus callosum had disappeared completely.

CONCLUSIONS

MERS is a clinical/radiological syndrome with a generally good prognosis. We believe that this is the first description of a case of Shigella-associated MERS. It is useful to know about this condition to help distinguish it from acute disseminated encephalomyelitis.

Clinical impact of a gastrointestinal PCR panel in children with infectious diarrhoea

OBJECTIVES

Multiplex gastrointestinal PCR (GI-PCR) allows fast and simultaneous detection of 22 enteric pathogens (including Campylobacter, Salmonella, Shigella/enteroinvasive Escherichia coli (EIEC), among other bacteria, parasites and viruses). However, its impact on the management of children with infectious diarrhoea remains unknown.

PATIENTS/DESIGN

All children eligible for stool culture from May to October 2018 were prospectively included in a monocentric study at Robert-Debré University-Hospital.

INTERVENTION

A GI-PCR (BioFire FilmArray) was performed on each stool sample.

MAIN MEASURES

Data on the children's healthcare management before and after GI-PCR results were collected. Stool culture results were also reported.

RESULTS

172 children were included. The main criteria for performing stool analysis were mucous/bloody diarrhoea and/or traveller's diarrhoea (n=130). GI-PCR's were positive for 120 patients (70%). The main pathogens were enteroaggregative E. coli (n=39; 23%), enteropathogenic E. coli (n=34; 20%), Shigella/EIEC (n=27; 16%) and Campylobacter (n=21; 12%). Compared with stool cultures, GI-PCR enabled the detection of 21 vs 19 Campylobacter, 12 vs 10 Salmonella, 27 Shigella/EIEC vs 13 Shigella, 2 vs 2 Yersinia enterocolitica, 1 vs 1 Plesiomonas shigelloides, respectively. Considering the GI-PCR results and before stool culture results, the medical management was revised for 40 patients (23%): 28 initiations, 2 changes and 1 discontinuation of antibiotics, 1 hospitalisation, 2 specific room isolations related to Clostridioides difficile infections, 4 additional test prescriptions and 2 test cancellations.

CONCLUSION

The GI-PCR's results impacted the medical management of gastroenteritis for almostone-fourth of the children, and especially the prescription of appropriate antibiotic treatment before stool culture results.

Week 4 viral load predicts long-term suppression of hepatitis B virus DNA during antiviral therapy: improving hepatitis B treatment in the real world

BACKGROUND

Entecavir and tenofovir potently suppress hepatitis B virus (HBV) replication so that serum HBV DNA levels <20 IU/mL can be achieved after 2 years. Despite this, inadequate suppression is reported in >20% of cases for unclear reasons.

AIM

We tested whether 4-week viral load (VL) assessment could improve 96-week treatment outcome.

METHODS

Data on all chronic hepatitis B patients treated with entecavir or tenofovir between 2005 and 2014 were entered prospectively. Full data capture included pre-treatment, weeks 4, 24, 48 and 96 HBV DNA titre, HBeAg, age, gender, antiviral agent and dose escalation. Compliance data were compiled from pharmacy records, doctors' letters and clinic bookings/attendance. Time to achieve complete viral suppression (HBV DNA < 20 IU/mL) was graphed using Kaplan-Meier curves. Factors affecting this were examined using a multivariate Cox Proportional Hazard model.

RESULTS

Among 156 patients treated, 72 received entecavir and 84 tenofovir. Pre-treatment HBV DNA titre, 4-week assessment and compliance impacted significantly on time to complete viral suppression. At 96 weeks, 90% of those assessed as compliant by 4-week HBV DNA had complete viral suppression versus 50% followed by 6-month VL estimation. Continuing care by the same physician was related to 4-week VL testing and optimal compliance.

CONCLUSIONS

Medium-term outcomes of HBV antiviral therapy are improved by early on-treatment VL testing, facilitating patient engagement and improved compliance. The observation that 90% complete viral suppression after 2 years monotherapy is achievable in a routine clinic setting questions the need for combination therapy in HBV cases with suboptimal response.

Macroscopic hematuria with normal renal biopsy-following the chain to the diagnosis: Answers

BACKGROUND

Alport syndrome (AS) is an inherited glomerular disease associated with hearing and eye defects; its morbidity is a public health issue in developed countries. AS results from mutations in COL4A3, COL4A4, or COL4A5 genes, respectively encoding the alpha-3, alpha-4, and alpha-5 chains of type IV collagen, a major component of the renal glomerular basement membrane (GBM). The diagnosis is usually confirmed by a renal biopsy showing a thinning/thickening of the GBM, with a longitudinal splitting of the lamina densa.

CASE DIAGNOSIS

We report the case of a 10-year-old patient who presented multiple episodes of macroscopic hematuria. On the renal biopsy, the electron microscopy analysis of the GBM was normal, as was the COL4A5 immunofluorescence assay. Genetic analyses showed a homozygous duplication of exons 44 to 47 of the COL4A3 gene, confirming the diagnosis of autosomal recessive AS.

CONCLUSIONS

Our report suggests that in patients with clinical evidence of AS, genetic testing should be performed whenever pathological analysis is not in favor of AS diagnosis. This will ensure that AS patients benefit from an early diagnosis, adequate treatment, and that end-stage renal disease (ESRD) onset is delayed.

Demonstration of ignition radiation temperatures in indirect-drive inertial confinement fusion hohlraums

We demonstrate the hohlraum radiation temperature and symmetry required for ignition-scale inertial confinement fusion capsule implosions. Cryogenic gas-filled hohlraums with 2.2 mm-diameter capsules are heated with unprecedented laser energies of 1.2 MJ delivered by 192 ultraviolet laser beams on the National Ignition Facility. Laser backscatter measurements show that these hohlraums absorb 87% to 91% of the incident laser power resulting in peak radiation temperatures of T(RAD)=300 eV and a symmetric implosion to a 100 μm diameter hot core.

Concentrations and chiral signatures of POPs in soils and sediments: a comparative urban versus rural study in Canada and UK

Surface soils and sediments were collected in Toronto, Canada to investigate the concentrations and enantiomeric signatures of urban versus rural locations. Samples were analyzed for polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs) and organochlorine pesticides (OCs). In soils, the sum of 10 PCB congeners (Sigma PCB 28, 52, 95, 101, 118, 136, 138, 149, 153, 180) and 15 PAHs (Sigma PAHs) ranged from 0.76-58 to 58-3200 ng g(-1), respectively. The most abundant OCs detected were DDTs, followed by chlordanes and endosulfans. Sigma PAHs exhibited an urban-rural gradient of up to 60 times but a gradient was not observed for Sigma PCBs and OCs which may reflect local sources of these chemicals. In sediments, Sigma PCBs and Sigma PAHs ranged from 0.03-23 ng g(-1) to 42-3300 ng g(-1), respectively. Sigma PCBs, Sigma PAHs, chlordanes and DDTs exhibited weak urban-rural gradients. Chiral signatures of PCB 95, 136, 149, trans-chlordane (TC), cis-chlordane (CC) and o,p-DDT were characterized to study the enantiomeric degradation in urban versus rural areas and its relation to contaminant levels. Supplementary to these data, we also report on the chiral signatures of PCBs in UK lake sediments from a variety of urban and rural locations. The extent of enantiomeric degradation was expressed as the enantiomeric excess (EE%) which is defined as 100x(E1-E2)/(E1+E2), where E1 is always the most abundant enantiomer and E2 is the least abundant enantiomer. The EE% of PCB 149 in the UK sediments was negatively correlated (p<0.05) with Sigma PAHs suggesting either more recent emissions of this PCB congener in the more contaminated urban locations and hence a more racemic signature or less enantiomeric degradation of the congener in more contaminated urban soils. However, no significant correlation was observed between EE% of any of the chiral chemicals and contaminant levels in the Toronto soils.

Identification of two novel HLA class II alleles, DQB1*030503 and DRB1*0447

Two novel human leukocyte antigen (HLA) class II alleles have been identified in routine typing of bone marrow donors for the Australian Bone Marrow Donor Registry in Sydney, Australia. Sequence analysis of exon 2 of both the DQB1 and DRB1 genes revealed the novel polymorphism. A silent substitution of G to A at nucleotide position 210 has been identified for the DQB1*030503 allele when compared to the closest matched allele, DQB1*030501. There is no associated amino acid difference between the translated products of the two alleles. The second new allele is a variant of the DRB1 gene. The DRB1*0447 allele was identified with three nucleotide substitutions compared to the closest matched allele DRB1*0436. There is a silent mutation at nucleotide position 303, G to C and two substitutions at adjacent nucleotide positions 344 and 345, T to G and G to T, respectively. The latter two substitutions result in an amino acid change from valine to glycine at position 86, implicating a different specificity and affinity of antigen binding.

A new HLA-B allele, B*1565, identified in three unrelated samples

Anew human leukocyte antigen-B allele, B*1565, has been identified during routine typing of cord blood samples. Subsequently, two individuals from the same family as the first cord blood sample plus two unrelated Australian Bone Marrow Donor Registry samples have been found to carry this novel allele.

A splice variant of the ITF-2 transcript encodes a transcription factor that inhibits MyoD activity

Proteins of the basic helix-loop-helix (bHLH) family are transcription factors that bind DNA containing the E box motif (CANNTG) found in the promoters of many muscle-specific genes. ITF-2 is a bHLH protein with widespread expression that is thought to form active heterodimers with MyoD, a muscle-specific bHLH transcription factor. We have isolated cDNAs derived from two alternatively spliced forms of mouse ITF-2, termed MITF-2A and -2B. These proteins differ in their N termini. Neither MITF-2A nor -2B transactivated the cardiac alpha-actin promoter, which contains an E box, when transfected into nonmuscle cells. In fact, MITF-2B inhibited MyoD activation of the cardiac alpha-actin promoter. This inhibitory activity required the N-terminal 83 amino acids since MITF-2A showed no inhibitory activity, and a mutant MITF-2B with deletion of the N-terminal 83 amino acids failed to inhibit MyoD-mediated transcriptional activation. MyoD activity was also inhibited by Id, a HLH protein, and this inhibition was reversed by the addition of excess E12 or MITF-2A. However, the inhibition of MyoD activity by MITF-2B was not reversed with E12 or MITF-2A. While Id is thought to inhibit MyoD by binding and sequestering potential dimerization partners, MITF-2B appears to inhibit MyoD activity by forming an inactive heterodimer with MyoD. Thus, differentially spliced transcripts of mouse ITF-2 encode different proteins that appear to dimerize with MyoD and activate or repress transcription.