Iron is indispensable for human life. However, it is also potentially toxic, since it catalyzes the formation of harmful oxidative radicals in unbound form and may facilitate pathogen growth. ...Therefore, iron homeostasis needs to be tightly regulated. Rapid growth and development require large amounts of iron, while (especially young) children are vulnerable to infections with iron-dependent pathogens due to an immature immune system. Moreover, unbalanced iron status early in life may have effects on the nervous system, immune system and gut microbiota that persist into adulthood. In this narrative review, we assess the critical roles of iron for growth and development and elaborate how the body adapts to physiologically high iron demands during the journey from fetus to adolescent. As a first step towards the development of clinical guidelines for the management of iron disorders in children, we summarize the unmet needs regarding the developmental aspects of iron homeostasis.
Up to 7% of term and late-preterm neonates in high-income countries receive antibiotics during the first 3 days of life because of suspected early-onset sepsis. The prevalence of culture-proven ...early-onset sepsis is 0·1% or less in high-income countries, suggesting substantial overtreatment. We assess whether procalcitonin-guided decision making for suspected early-onset sepsis can safely reduce the duration of antibiotic treatment.
We did this randomised controlled intervention trial in Dutch (n=11), Swiss (n=4), Canadian (n=2), and Czech (n=1) hospitals. Neonates of gestational age 34 weeks or older, with suspected early-onset sepsis requiring antibiotic treatment were stratified into four risk categories by their treating physicians and randomly assigned 1:1 using a computer-generated list stratified per centre to procalcitonin-guided decision making or standard care-based antibiotic treatment. Neonates who underwent surgery within the first week of life or had major congenital malformations that would have required hospital admission were excluded. Only principal investigators were masked for group assignment. Co-primary outcomes were non-inferiority for re-infection or death in the first month of life (margin 2·0%) and superiority for duration of antibiotic therapy. Intention-to-treat and per-protocol analyses were done. This trial was registered with ClinicalTrials.gov, number NCT00854932.
Between May 21, 2009, and Feb 14, 2015, we screened 2440 neonates with suspected early-onset sepsis. 622 infants were excluded due to lack of parental consent, 93 were ineligible for reasons unknown (68), congenital malformation (22), or surgery in the first week of life (3). 14 neonates were excluded as 100% data monitoring or retrieval was not feasible, and one neonate was excluded because their procalcitonin measurements could not be taken. 1710 neonates were enrolled and randomly assigned to either procalcitonin-guided therapy (n=866) or standard therapy (n=844). 1408 neonates underwent per-protocol analysis (745 in the procalcitonin group and 663 standard group). For the procalcitonin group, the duration of antibiotic therapy was reduced (intention to treat: 55·1 vs 65·0 h, p<0·0001; per protocol: 51·8 vs 64·0 h; p<0·0001). No sepsis-related deaths occurred, and 9 (<1%) of 1710 neonates had possible re-infection. The risk difference for non-inferiority was 0·1% (95% CI −4·6 to 4·8) in the intention-to-treat analysis (5 0·6% of 866 neonates in the procalcitonin group vs 4 0·5% of 844 neonates in the standard group) and 0·1% (−5·2 to 5·3) in the per-protocol analysis (5 0·7% of 745 neonates in the procalcitonin group vs 4 0·6% of 663 neonates in the standard group).
Procalcitonin-guided decision making was superior to standard care in reducing antibiotic therapy in neonates with suspected early-onset sepsis. Non-inferiority for re-infection or death could not be shown due to the low occurrence of re-infections and absence of study-related death.
The Thrasher Foundation, the NutsOhra Foundation, the Sophia Foundation for Scientific research.
Abstract
Background
Neonatal early-onset sepsis (EOS) is one of the main causes of global neonatal mortality and morbidity, and initiation of early antibiotic treatment is key. However, antibiotics ...may be harmful.
Methods
We performed a secondary analysis of results from the Neonatal Procalcitonin Intervention Study, a prospective, multicenter, randomized, controlled intervention study. The primary outcome was the diagnostic accuracy of serial measurements of C-reactive protein (CRP), procalcitonin (PCT), and white blood count (WBC) within different time windows to rule out culture-positive EOS (proven sepsis).
Results
We analyzed 1678 neonates with 10 899 biomarker measurements (4654 CRP, 2047 PCT, and 4198 WBC) obtained within the first 48 hours after the start of antibiotic therapy due to suspected EOS. The areas under the curve (AUC) comparing no sepsis vs proven sepsis for maximum values of CRP, PCT, and WBC within 36 hours were 0.986, 0.921, and 0.360, respectively. The AUCs for CRP and PCT increased with extended time frames up to 36 hours, but there was no further difference between start to 36 hours vs start to 48 hours. Cutoff values at 16 mg/L for CRP and 2.8 ng/L for PCT provided a sensitivity of 100% for discriminating no sepsis vs proven sepsis.
Conclusions
Normal serial CRP and PCT measurements within 36 hours after the start of empiric antibiotic therapy can exclude the presence of neonatal EOS with a high probability. The negative predictive values of CRP and PCT do not increase after 36 hours.
During recent years, our understanding of the pathogenesis of inherited microcytic anemias has gained from the identification of several genes and proteins involved in systemic and cellular iron ...metabolism and heme syntheses. Numerous case reports illustrate that the implementation of these novel molecular discoveries in clinical practice has increased our understanding of the presentation, diagnosis, and management of these diseases. Integration of these insights into daily clinical practice will reduce delays in establishing a proper diagnosis, invasive and/or costly diagnostic tests, and unnecessary or even detrimental treatments. To assist the clinician, we developed evidence-based multidisciplinary guidelines on the management of rare microcytic anemias due to genetic disorders of iron metabolism and heme synthesis. These genetic disorders may present at all ages, and therefore these guidelines are relevant for pediatricians as well as clinicians who treat adults. This article summarizes these clinical practice guidelines and includes background on pathogenesis, conclusions, and recommendations and a diagnostic flowchart to facilitate using these guidelines in the clinical setting.
Pathogenic
variants impairing matriptase-2 function result in inappropriately high hepcidin levels relative to body iron status, leading to iron refractory iron deficiency anemia (IRIDA). As ...diagnosing IRIDA can be challenging due to its genotypical and phenotypical heterogeneity, we assessed the transferrin saturation (TSAT)/hepcidin ratio to distinguish IRIDA from multi-causal iron deficiency anemia (IDA). We included 20 IRIDA patients from a registry for rare inherited iron disorders and then enrolled 39 controls with IDA due to other causes. Plasma hepcidin-25 levels were measured by standardized isotope dilution mass spectrometry. IDA controls had not received iron therapy in the last 3 months and C-reactive protein levels were <10.0 mg/L. IRIDA patients had significantly lower TSAT/hepcidin ratios compared to IDA controls, median 0.6%/nM (interquartile range, IQR, 0.4-1.1%/nM) and 16.7%/nM (IQR, 12.0-24.0%/nM), respectively. The area under the curve for the TSAT/hepcidin ratio was 1.000 with 100% sensitivity and specificity (95% confidence intervals 84-100% and 91-100%, respectively) at an optimal cut-off point of 5.6%/nM. The TSAT/hepcidin ratio shows excellent performance in discriminating IRIDA from
-unrelated IDA early in the diagnostic work-up of IDA provided that recent iron therapy and moderate-to-severe inflammation are absent. These observations warrant further exploration in a broader IDA population.
Iron-refractory iron deficiency anemia (IRIDA) is an autosomal recessive inherited form of iron deficiency anemia characterized by discrepantly high hepcidin levels relative to body iron status. ...However, patients with monoallelic exonic TMPRSS6 variants have also been reported to express the IRIDA phenotype. The pathogenesis of an IRIDA phenotype in these patients is unknown and causes diagnostic uncertainty. Therefore, we retrospectively summarized the data of 16 patients (4 men, 12 women) who expressed the IRIDA phenotype in the presence of only a monoallelic TMPRSS6 variant. Eight unaffected relatives with identical exonic TMPRSS6 variants were used as controls. Haplotype analysis was performed to assess the (intra)genetic differences between patients and relatives. The expression and severity of the IRIDA phenotype were highly variable. Compared with their relatives, patients showed lower Hb, MCV, and TSAT/hepcidin ratios and inherited a different wild-type allele. We conclude that IRIDA in monoallelic TMPRSS6-affected patients is a phenotypically and genotypically heterogeneous disease that is more common in female patients. We hypothesize that allelic imbalance, polygenetic inheritance, or modulating environmental factors and their complex interplay are possible causes. This explorative study is the first step toward improved insights into the pathophysiology and improved diagnostic accuracy for patients presenting with IRIDA and a monoallelic exonic TMPRSS6 variant.
In critically ill (preterm) neonates, catheter-related venous thromboembolism (CVTE) can be a life-threatening complication. Evidence on optimal management in the literature is lacking. In the ...Netherlands, a consensus-based national management guideline was developed to create uniform CVTE management.
To evaluate the efficacy and safety of the national guideline.
This prospective, multicenter, observational study included all infants aged ≤6 months with CVTE in the Netherlands between 2014 and 2019. CVTE was divided into thrombosis in veins and that in the right atrium, with their own treatment algorithms. The primary outcomes were recurrent venous thrombotic events (VTEs) and/or death due to CVTE as well as major bleeding.
Overall, 115 neonates were included (62% male; 79% preterm). The estimated incidence of CVTE was 4.0 per 1000 neonatal intensive care unit admissions. Recurrent thrombosis occurred in 2 (1.7%) infants and death due to CVTE in 1 (0.9%) infant. Major bleeding developed in 9 (7.8%) infants: 2 of 7 (29%) on recombinant tissue plasminogen activator, which was given for high-risk right-atrium thrombosis, and 7 of 63 (11%) on low-molecular-weight heparin (LMWH). Five of the 7 bleedings because of LMWH were complications of subcutaneous catheter use for LMWH administration.
The management of neonatal CVTE according to the Dutch CVTE management guideline led to a low incidence of recurrent VTEs and death due to VTEs. Major bleeding occurred in 7.8% of the infants. Specific guideline adjustments may improve efficacy and, especially, safety of CVTE management in neonates.
Current strategies for risk stratification and prediction of neonatal early-onset sepsis (EOS) are inefficient and lack diagnostic performance. The aim of this study was to use machine learning to ...analyze the diagnostic accuracy of risk factors (RFs), clinical signs and biomarkers and to develop a prediction model for culture-proven EOS. We hypothesized that the contribution to diagnostic accuracy of biomarkers is higher than of RFs or clinical signs.
Secondary analysis of the prospective international multicenter NeoPInS study. Neonates born after completed 34 weeks of gestation with antibiotic therapy due to suspected EOS within the first 72 hours of life participated. Primary outcome was defined as predictive performance for culture-proven EOS with variables known at the start of antibiotic therapy. Machine learning was used in form of a random forest classifier.
One thousand six hundred eighty-five neonates treated for suspected infection were analyzed. Biomarkers were superior to clinical signs and RFs for prediction of culture-proven EOS. C-reactive protein and white blood cells were most important for the prediction of the culture result. Our full model achieved an area-under-the-receiver-operating-characteristic-curve of 83.41% (±8.8%) and an area-under-the-precision-recall-curve of 28.42% (±11.5%). The predictive performance of the model with RFs alone was comparable with random.
Biomarkers have to be considered in algorithms for the management of neonates suspected of EOS. A 2-step approach with a screening tool for all neonates in combination with our model in the preselected population with an increased risk for EOS may have the potential to reduce the start of unnecessary antibiotics.
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