Left atrial remodeling in adolescents with obesity evaluated by speckle-tracking echocardiography.

BACKGROUND AND AIMS: In adolescents with obesity, a left atrial (LA) enlargement has been reported. However, data regarding its function and its stiffness are missing. The aim of this study was to describe LA morphology and function, using speckle-tracking echocardiography (STE) and to explore their potential determinants in adolescents with obesity. METHODS: Twenty-eight adolescent women with obesity (13.2 ± 1.4 yr) with an illness duration of 130 ± 27 months and 33 controls (14.1 ± 2.0 yr) underwent a resting echocardiography including an analysis of left ventricular (LV) and LA morphologies and strains. A fasting venous blood sample was performed to biochemical determinations including inflammation markers. RESULTS: LA volume and stiffness index were increased in adolescents with obesity compared to controls. LA reservoir, conduit and booster pump functions were not different between groups. By stepwise forward multivariate regression analyses, systolic blood pressures, cardiac output and sedimentation rate were the independent determinants of LA volume (p < 0.0001, ß-coefficient = 0.460) whereas only the body mass index was an independent determinant of LA stiffness (p = 0.003, ß-coefficient = 0.413). CONCLUSION: In adolescents with obesity, we observed a specific LA remodeling, including higher volume and lower stiffness, which could constitute early signs of an altered LV diastolic function.

Robot-assisted gait training improves walking and cerebral connectivity in children with unilateral cerebral palsy.

BACKGROUND: Robot-assisted gait training (RAGT) is promising to help walking rehabilitation in cerebral palsy, but training-induced neuroplastic effects have little been investigated. METHODS: Forty unilateral cerebral palsy children aged 4-18 years were randomly allocated in a monocentric study to ten 20-minute RAGT sessions with the G-EO system, five days a week (n = 20) or to a control group (who continued conventional care with six 30-minute physiotherapy sessions, three days a week) (n = 20), two weeks running, from September 2020 to December 2021. Clinical and MRI outcomes were compared before and one month after therapy. The primary outcome was gait speed. Secondary outcomes were a 6-minute walking test distance, Gross Motor Function Measure-88 (GMFM-88) dimensions D and E, Patient Global Impression of Improvement, resting-state functional connectivity within the sensorimotor network, and structural connectivity in the corticospinal tracts. RESULTS: Gait speed and the 6-minute walking test distance improved more after RAGT. Resting-state functional connectivity increased after RAGT but decreased in controls between superior and lateral healthy or lateral injured sensorimotor networks. GMFM-88 and structural connectivity in corticospinal tracts were unchanged. Impression of improvement in children was better after RAGT. CONCLUSION: Short-term benefit of repetitive RAGT on walking abilities and functional cerebral connectivity was found in unilateral cerebral palsy children. IMPACT STATEMENT: Short-term repetitive robot-assisted gait training improves gait speed and walking resistance and increases cerebral functional connectivity in unilateral cerebral palsy. GMFM dimensions D and E were unchanged after short-term repetitive robot-assisted gait training in unilateral cerebral palsy.

Fitness and metabolic response to exercise in young adult survivors of childhood lymphoma.

PURPOSE: Childhood lymphoma survivors (CLSs) are at high risk of reduced daily activity. This work studied metabolic substrate use and cardiorespiratory function in response to exercise in CLSs. METHODS: Twenty CLSs and 20 healthy adult controls matched for sex, age, and BMI took an incremental submaximal exercise test to determine fat/carbohydrate oxidation rates. Resting echocardiography and pulmonary functional tests were performed. Physical activity level, and blood metabolic and hormonal levels were measured. RESULTS: CLSs reported more physical activity than controls (6317 ± 3815 vs. 4268 ± 4354 MET-minutes/week, p = 0.013), had higher resting heart rate (83 ± 14 vs. 71 ± 13 bpm, p = 0.006), and showed altered global longitudinal strain (- 17.5 ± 2.1 vs. - 19.8 ± 1.6%, p = 0.003). We observed no difference in maximal fat oxidation between the groups, but it was reached at lower relative exercise intensities in CLSs (Fatmax 17.4 ± 6.0 vs. 20.1 ± 4.1 mL/kg, p = 0.021). At V̇O2 peak, CLSs developed lower relative exercise power (3.2 ± 0.9 vs. 4.0 ± 0.7 W/kg, p = 0.012). CONCLUSION: CLSs reported higher levels of physical activity but they attained maximal fat oxidation at lower relative oxygen uptake and applied lower relative power at V̇O2 peak. CLSs may thus have lower muscular efficiency, causing greater fatigability in response to exercise, possibly related to chemotherapy exposure during adolescence and childhood. Long-term follow-up is essential and regular physical activity needs to be sustained.

Triage nurse-initiated X-ray radiography in minor trauma.

BACKGROUND: Overcrowding of paediatric emergency departments (EDs) is a worldwide issue, where improving the quality of care is a priority. The main objective of this study was to determine the effect of triage nurse-initiated X-ray radiography on length of stay in paediatric emergency admissions. METHODS: This retrospective, monocentric, descriptive study was performed in two successive 3-month periods: a pre-protocol ('before') period from 3 February to 3 May 2020 and a protocol ('after') period from 4 May to 2 August 2020, when patients underwent nurse-initiated X-ray radiography. The study involved all patients who were aged ≥3 years, valid, non-hyperalgic, accompanied by their parents and consulting at the paediatric ED for a simple closed distal trauma, involving a single limb segment or joint. RESULTS: A total of 695 patients were included, 298 in the first period and 397 in the second period. The median length of stay in the paediatric ED was significantly shorter during the second period (119 min [80, 165] vs. 80 min [60, 105], P < 0.001), i.e. a median reduction time of 39 min or 33% (effect size = - 0.68, 95% confidence interval [-0.84 to -0.53]). Triage nurse requests were judged 'adequate and sufficient' in 95.2% of cases, with only 2.0% of instances deemed 'unnecessary' by the medical team. In 2.8% of cases, 'another X-ray' was required to support diagnosis. CONCLUSIONS: The application of a triage nurse X-ray protocol significantly reduced the length of stay in a paediatric ED. The quality of patient management remained unchanged, and nurse requests were relevant.

Infrared augmented reality device versus standard procedure for peripheral venous catheterisation in children less than 3 years old: A quasi-experimental cluster randomised controlled trial.

AIM AND OBJECTIVE: The objective of this study was to evaluate the AccuVeinAV400® viewing device for peripheral venous catheter insertion in children on the first try. BACKGROUND: Inserting a peripheral venous catheter is the most frequent invasive procedure carried out by healthcare professionals in hospitalised children. Several attempts are sometimes necessary, and veins can be damaged. DESIGN: A quasi-experimental cluster randomised controlled trial based on the CONSORT 2010 guidelines. METHODS: This randomised study comparing standard practice to the use of AccuVein400® was carried out on children who were less than 3 years old, with difficult intravenous access (DIVA Score), hospitalised in three paediatric units and who needed cannulation. RESULT: A total of 304 children were included (156 in the AccuVein arm and 148 in the standard arm). There was no significant difference between AccuVein and standard groups in age (respectively, 2.5 ± 0.9 years vs. 2.5 ± 0.8), or mean DIVA score (respectively 5.9 ± 1.3 vs. 5.5 ± 1.2). The success of cannulation on the first attempt was 40.38% in the AccuVein arm vs. 41.2% in the standard arm (p = .6). The caregiver's assessment of pain on the Face Legs Activity Cry Consolability scale was 4.8 ± 0.2 in the AccuVein arm vs. 5.0 ± 0.2 (p = .4). CONCLUSIONS: The use of AccuVein400® did not lead to greater success in intravenous insertion at the first attempt in children under 3 years of age with difficult intravenous access. RELEVANCE TO CLINICAL PRACTICE: This device can therefore be used according to the healthcare professionals' situation and needs. It is widely used in paediatric wards, and our study shows that it offers a support tool that reassures healthcare professionals and helps validate their choice of vein easiest to catheterise.

Peripheral blood stem cell collection in children with extremely low body weight (≤8 kg). What have we learned over the past 25 years and where are the limits?

Hematopoietic progenitor cells-apheresis (HPC-A) collection is now a routine procedure for autologous hematopoietic stem cell transplantation. Here we present our 25 years' experience of HPC-A collection in children weighing 8 kg or less, with a focus on the evolution of our standard operating procedures, and the safety limits for these young patients, in the Pediatric Apheresis Unit of Clermont-Ferrand University Hospital (France). Fifteen children weighing 8 kg or less underwent 26 HPC-A collections over 25 years. Median CD34+ cell yield by leukapheresis was 4.4 106 /kg. No procedure-related complications were encountered during or after the collection. No patient had profound thrombocytopenia or anemia that needed post-collection transfusions. Our experience in pediatric oncology patients who underwent HPC-A collections shows that this procedure can be performed even in the smallest of children with no increase in toxicity provided all precautions are taken to ensure that the procedure is carried out under the ideal conditions.

Muscle function and architecture in children with juvenile idiopathic arthritis.

AIM: To assess muscle function and functional abilities in children with juvenile idiopathic arthritis (JIA). METHODS: Fourteen children with JIA and 14 healthy controls matched for age and sex were included. Muscle characteristics, both structural (thickness, cross-sectional area (CSA) and fascicle angle) and qualitative (intermuscular adipose tissue; IMAT), were assessed in thigh muscles using ultrasound and peripheral quantitative computed tomography (pQCT). Muscle function and functional abilities were determined from the assessment of maximal voluntary isometric contraction (MVIC) knee extensors force and vertical jump performance. RESULTS: No significant difference in MVIC force was observed between the two groups. However, squat jump height was significantly reduced in children with JIA (18.3 ± 5.4 vs 24.3 ± 7.9 cm, P < .05). No differences in structural parameters were observed, but IMAT/CSA (0.22 ± 0.02 vs 0.25 ± 0.03; P = .01) was significantly lower in children with JIA than in healthy children. CONCLUSION: Knee extensor muscle architecture and force were comparable between children with and without JIA, but functional abilities (vertical jump performance) were poorer in JIA. The lower IMAT area in JIA could result from a lower physical activity level compared with healthy children.

Cold Vibration (Buzzy) Versus Anesthetic Patch (EMLA) for Pain Prevention During Cannulation in Children: A Randomized Trial.

INTRODUCTION: The purpose of this study was to assess differences in observed pain-related behaviors during cannulation between a device combining cold and vibration (Buzzy) and the standard care (EMLA patch). METHODS: Patients 18 months to 6 years old, requiring venous access in a pediatric emergency department, received either the Buzzy device or the EMLA patch. Predefined week randomization ensured equal allocation to the 2 intervention groups. Pain during cannulation was measured using the Children's Hospital of Eastern Ontario Pain Scale. Parent and nurse reports, cannulation success, and venous access times were also assessed. RESULTS: In total, 607 included patients were randomized into the Buzzy group (n = 302) or the EMLA group (n = 305). Observed pain-related behaviors scores, parent-assessed pain scores, and nurse-reported pain ratings were higher with Buzzy. CONCLUSIONS: Pain relief by a combination of cold and vibration during cannulation is not as effective as the standard-care method in children 18 months to 6 years old.

Metabolic response to exercise in childhood brain tumor survivors: A pilot controlled study.

BACKGROUND/OBJECTIVES: Survival rates in children diagnosed with malignant brain tumors exceed 70%. A higher risk of dyslipidemia, central obesity, and insulin resistance has been reported among these children. We investigated substrate utilization during submaximal exercise. DESIGN/METHODS: Ten brain tumor survivors and 10 healthy children were matched by sex, age, and Tanner stage. Participants completed a submaximal incremental exercise test to determine their fat and carbohydrate oxidation rates. RESULTS: The relative oxygen volume (VO2 ) peak was significantly higher in the control group than in the survivors of childhood brain tumors (43.3 ± 11.9 and 32.4 ± 10.2 mL/kg /min, P = .04). At the same relative exercise intensity, there was no difference in the carbohydrate or lipid oxidation rate between the two groups, or in the maximal fat oxidation (MFO) rate, or in the heart rate or percentage of VO2 peak to reach MFO. Healthy children achieved MFO at significantly higher muscular power than did brain tumor survivors (47.9 ± 20.8 and 21.8 ± 9.6 W, P = .003). CONCLUSION: Because child brain tumor survivors are less physically fit than healthy children, and substrate utilization during submaximal exercise is not different, physical activity should be promoted for child brain tumor survivors.

Physical activity and sedentary levels in children with juvenile idiopathic arthritis and inflammatory bowel disease. A systematic review and meta-analysis.

BACKGROUND: Physical activity (PA) is essential for children throughout their growth and maturation. It improves physiological and psychological health and limits the risk of developing metabolic disorders. However, some chronic physiological and metabolic diseases may lead to decreased PA. The diversity of outcomes in the literature offers no consensus for physical activity and sedentary levels in children with juvenile idiopathic arthritis (JIA) or inflammatory bowel disease (IBD). METHODS: A literature review and a meta-analysis were carried out with original studies from a Medline database search. Only high-quality studies (STROBE checklist) written in English comparing PA level or sedentary behavior (SB) between children with the disorders and their healthy peers were considered. The aim was to examine PA and SB in children with JIA or IBD compared to their healthy peers. RESULTS: The literature review and meta-analysis identified decreased PA and increased time spent in SB in these populations, which may exacerbate both their lower physical fitness and the symptoms of their health disorders. CONCLUSION: Results nevertheless show discrepancies due to the different materials and methods used and the variables measured. Further studies are needed to establish a gold standard method for assessing PA level in these populations.

RSV-hRV co-infection is a risk factor for recurrent bronchial obstruction and early sensitization 3 years after bronchiolitis.

To assess risk factors of recurrent bronchial obstruction and allergic sensitization 3 years after an episode of acute bronchiolitis, whether after ambulatory care treatment or hospitalization. A monocentric prospective longitudinal study including infants aged under 1 year with acute bronchiolitis was performed, with clinical (severity score), biological (serum Krebs von den Lungen 6 antigen), and viral (14 virus by naso-pharyngeal suction detection) assessments. Follow-up included a quaterly telephone interview, and a final clinical examination at 3 years. Biological markers of atopy were also measured in peripheral blood, including specific IgEs towards aero- and food allergens. Complete data were available for 154 children. 46.8% of them had recurrent wheezing (RW). No difference was found according to initial severity, care at home or in the hospital, respiratory virus involved, or existence of co-infection. A familial history of atopy was identified as a risk factor for recurrent bronchial obstruction (60% for RW infants versus 39%, P = 0.02), as living in an apartment (35% versus 15%, P = 0.002). 18.6% of the infants were sensitized, with 48.1% of them sensitized to aeroallergens and 81.5% to food allergens. Multivariate analysis confirmed that a familial history of atopy (P = 0.02) and initial co-infection RSV-hRV (P = 0.02) were correlated with the risk of sensitization to aeroallergens at 3 years. Familial history of atopy and RSV-hRV co-infection are risk factors for recurrent bronchial obstruction and sensitization.

Single Bout Exercise in Children with Juvenile Idiopathic Arthritis: Impact on Inflammatory Markers.

Objective: In a context of inflammatory disease such as juvenile idiopathic arthritis (JIA), we do not know what impact physical activity may have on a deregulated immune system. The objective is to measure the impact of a single bout of exercise on plasma inflammatory markers such as calprotectin, IL-6, sIL-6R, sgp130, and the hypothalamic-pituitary-adrenal axis in children with juvenile idiopathic arthritis. Methods: Twelve children with JIA performed a nonexercise control day and a consecutive day that included a 20 min exercise bout at 70% of max-HR at 08:30 am. Venous blood samples were taken at 08:30, 08:50, 09:30, 10:30 am, and 12:00 pm to measure plasma concentrations of calprotectin, IL-6, sIL-6R, sgp130, cortisol, and ACTH. Pain was evaluated at 08:30, 08:50 am, and 06:00 pm. Results: There was a transient twofold increase in postexercise self-evaluated pain (p = 0.03) that disappeared in the evening. A single bout of exercise resulted in a 1.7-fold increase in plasma calprotectin (p < 0.001) but not IL-6 and its soluble receptors. Calprotectin levels returned to baseline within 3 hours after cessation of exercise. Conclusion: Acute exercise in children with JIA induced slightly musculoskeletal leg pain and transient increased plasma calprotectin levels but not IL-6 levels. Trial registration in ClinicalTrials.gov, reference number NCT 02502539, registered on 29 May 2015.

Corrigendum to "Single Bout Exercise in Children with Juvenile Idiopathic Arthritis: Impact on Inflammatory Markers".

[This corrects the article DOI: 10.1155/2018/9365745.].

Inflammatory Response 24 h Post-Exercise in Youth with Juvenile Idiopathic Arthritis.

The aim of this study was to measure the impact, at 24 h post-exercise, of a single exercise bout on plasma inflammatory markers such as calprotectin, IL-6, sIL-6 R, sgp130 and the hypothalamic-pituitary-adrenal (HPA) axis in children with juvenile idiopathic arthritis (JIA).Twelve children with JIA attended the laboratory on three consecutive days (control day, exercise day and 24 h post-exercise), including a 20-min exercise bout on a cycle-ergometer at 70% of max. HR at 8:30 a.m. on day 2. Plasma concentrations of calprotectin, IL-6, sIL-6 R, sgp130, cortisol, ACTH and DHEA were measured on venous blood samples taken every day.at rest and at 8:30, 8:50, 9:30, 10:30 a.m. and 12:00, 3:00, 5:30 p.m.A single exercise bout increased plasma calprotectin 1.7-fold (p<0.001) but did not increase IL-6 and soluble IL-6 receptors in short-term post-exercise recovery. However, at 24 h post-exercise, calprotectin, IL-6 and its receptors had decreased compared to control-day levels. There was a transient 2-fold increase in post-exercise self-evaluated pain (p=0.03) that disappeared in the evening without repercussions the following day.Physical activity in children with JIA results in a slight transient systemic inflammation but seems to be followed by counter-regulation at 24 h post-exercise with a decrease in proinflammatory markers.

Leukapheresis in management of hyperleukocytosis in children's leukemias.

We describe 16 leukapheresis (LK) procedures performed in 7 children with different types of leukemia and hyperleukocytosis. We also provide an analysis of previously published experiences of pediatric LK. Median age and body weight of patients were 12.3 years (range, 0.2 to 16.7 y) and 49 kg (range, 5 to 61 kg). Immediate pre-first-LK median white blood cell count was 478×10/L (108×10/L to 988×10/L). All cytoreduction were performed on Cobe Spectra cell separator. Sixty-eight percent of procedures were performed with peripheral veins. Extracorporeal line had been primed with red blood cell for 31% of LK. The median decrease in white blood cell count after each LK was 33% (0% to 69%), and overall decrease after completion of LK procedures was 62% (11% to 94%). Only minor clinical adverse events and no metabolic complication were attributable to LK. No more clinical symptom of hyperleukocytosis was observed after completion of LK procedures. Our findings are consistent with reported results in other pediatric series: LK is a well-tolerated procedure that can be safely performed with an experienced pediatric team even on the smallest children.

Pathways of sleep disturbances in juvenile idiopathic arthritis and recommendations for clinical management approaches: A critical review.

Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease affecting young people. It has a profound impact on their physical, mental and social lives, leading to long-term disability. With the growing awareness of the importance of sleep in all areas of functioning in young people, an emerging literature has drawn attention to the role of sleep in the pathogenesis of JIA. Sleep disturbances in children and adolescents with JIA arise from a wide range of symptoms and pathways, leading to a vicious cycle that exacerbates subclinical inflammation, symptoms and disease progression. Putative factors contributing to sleep disturbances include chronic inflammation, JIA-associated sleep disorders, JIA symptoms (e.g. pain), psychological comorbidities and potential circadian disruption, which may be exacerbated by the transition to adolescence. Here, we review these pathways and advocate key strategies and alternatives for sleep management in young people with JIA in clinical settings. We identify gaps in knowledge and suggest future directions to improve our understanding of JIA sleep disorders, including clinical trials investigating potential strategies to improve sleep health in this young population.

Chrono-nutrition and sleep: lessons from the temporal feature of eating patterns in human studies - A systematic scoping review.

An emerging field of research has revealed a bidirectional relationship between sleep and diet, highlighting the potential role of a healthy diet in improving sleep. However, the impact of chrono-nutrition on sleep remains less explored. Here we conducted a systematic scoping review, considering the multiple dimensions of chrono-nutrition, to describe the extent, range, and nature of the existing literature in this area (PROSPERO: CRD42021274637). There has been a significant increase in the literature exploring this topic over the past six years (almost 67 % of the evolving literature). A breakdown of the included studies was performed according to three major chrono-nutritional dimensions: meal timing [n = 35], irregular eating patterns [n = 84], and frequency of eating occasions [n = 3]. Meal timing included three sub-dimensions: breakfast skipping [n = 13], late eating [n = 16], and earlier vs later meals schedules [n = 6]. Irregular meal patterns included three sub-dimensions: diurnal fasting [n = 65], intermittent fasting [n = 16], and daily meal patterns [n = 3]. Frequency was the least studied dimension (n = 3). We provided a synthetic and illustrative framework underlining important preliminary evidence linking the temporal characteristics of eating patterns to various facets of sleep health. Nonetheless, much work remains to be done to provide chrono-nutrition guidelines to improve sleep health in the general population.

Anthracycline-induced cardiotoxicity on regional myocardial work and left ventricular mechanical dispersion in adolescents and young adults in post-lymphoma remission.

BACKGROUND: Myocardial work (MW) is a new echocardiographic tool with a high sensitivity to detect early and subtle alterations of myocardial function. We aimed to evaluate the late effects of anthracyclines by assessing the global and segmental MW and intraventricular mechanical dispersion from speckle tracking echocardiography in childhood lymphoma survivors (CLS). METHODS: Thirty-one young adults including CLS and age-matched healthy controls were enrolled. All underwent echocardiography including an evaluation of left ventricular (LV) morphology and regional function. We assessed LV longitudinal (differentiating sub-endocardial and sub-epicardial layers), circumferential strains and twist, global and regional MW index (MWI). LV mechanical dispersion was assessed from the time dispersion of LV longitudinal strain, from myocardial wasted work (MWW) and myocardial work efficiency (MWE). RESULTS: The longitudinal strains both at the level of the sub-endocardium and sub-epicardium were reduced in CLS compared to controls. The global MWI was also decreased (1668 ± 266 vs 1870 ± 264%.mmHg in CLS patients and controls, respectively, p < 0.05), especially on the apical segments. An increase of LV intraventricular mechanical dispersion was observed in CLS. MWW and MWE remained unchanged compared to controls. CONCLUSION: Our results strongly support that cardiac remodeling is observed in CLS, characterized by a decrease in MW and an increase in LV mechanical dispersion. The apex is specifically altered, but its clinical significance remains uncertain. MW as a complement to strain seems interesting in cancer survivors to detect myocardial dysfunction at early stage and adapt their follow-up.

DeepMPTB: a vaginal microbiome-based deep neural network as artificial intelligence strategy for efficient preterm birth prediction.

In recent decades, preterm birth (PTB) has become a significant research focus in the healthcare field, as it is a leading cause of neonatal mortality worldwide. Using five independent study cohorts including 1290 vaginal samples from 561 pregnant women who delivered at term (n = 1029) or prematurely (n = 261), we analysed vaginal metagenomics data for precise microbiome structure characterization. Then, a deep neural network (DNN) was trained to predict term birth (TB) and PTB with an accuracy of 84.10% and an area under the receiver operating characteristic curve (AUROC) of 0.875 ± 0.11. During a benchmarking process, we demonstrated that our DL model outperformed seven currently used machine learning algorithms. Finally, our results indicate that overall diversity of the vaginal microbiota should be taken in account to predict PTB and not specific species. This artificial-intelligence based strategy should be highly helpful for clinicians in predicting preterm birth risk, allowing personalized assistance to address various health issues. DeepMPTB is open source and free for academic use. It is licensed under a GNU Affero General Public License 3.0 and is available at https://deepmptb.streamlit.app/ . Source code is available at https://github.com/oschakoory/DeepMPTB and can be easily installed using Docker ( https://www.docker.com/ ).

Mobilization of hematopoietic stem cells by plerixafor alone in children: a sequential Bayesian trial.

BACKGROUND: The rapid kinetics of hematopoietic stem cells induced by Plerixafor (Mozobil®, Genzyme) should be of particular interest in children. We therefore conducted a prospective trial to determine whether a one-day mobilization by plerixafor alone was efficient enough in children with cancer. METHODS: Children with solid malignancies were consecutively recruited for this phase-IIA, Bayesian single-center prospective study. Mobilization consisted in one subcutaneous injection of 240 µg plerixafor/kg body weight at 8a.m. (h0). Collection by apheresis began at h5 provided that CD34+count exceeded 10 × 10(6)/L. Our main evaluation criterion was percent of children in which at least 5 × 10(6) CD34+/kg could be collected during the first apheresis. RESULTS: No patients fulfilled the success criterion, and so a stopping criterion was met after 5 patients. All patients reached the threshold value of 10 × 10(6) CD34+cells/L post-injection and so all were eligible for apheresis. Peak CD34+cell values were ranged from 11 to 44 × 10(6)/L and were reached in 4h to 6h. No side-effects were observed. Median number of CD34+cells collected per patient BW was 1.62 × 10(6)[0.47-3.5]. In 3 of the 5 patients, collection was>1.5 × 10(6) CD34+/kg BW. CONCLUSION: In children, a 'one-day' mobilization regimen consisting of one injection of 240 µg/kg plerixafor alone in hematological steady state provides a faster and shorter mobilization than in adults. This strategy may be an attractive option for completing an insufficient graft. More studies are warranted to optimize the use of plerixafor in children.