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Background: Familial Mediterranean fever (FMF), caused by mutations in the pyrin-encoding MEFV gene, is characterized by uncontrolled caspase-1 activation and IL-1β secretion. A similar mechanism drives inflammation in cryopyrin-associated periodic fever syndrome (CAPS) caused by mutations in NLRP3. CAPS and FMF, however, result in largely different clinical manifestations, pointing to additional, autoinflammatory pathways involved in FMF. Another hallmark of FMF is extraordinarily high expression of S100A8 and S100A9. These alarmins are ligands of Toll-like receptor 4 and amplifiers of inflammation. However, the relevance of this inflammatory pathway for the pathogenesis of FMF is unknown., Objective: This study investigated whether mutations in pyrin result in specific secretion of S100A8/A9 alarmins through gasdermin D pores' amplifying FMF pathology., Methods: S100A8/A9 levels in FMF patients were quantified by enzyme-linked immunosorbent assay. In vitro models with knockout cell lines and specific protein inhibitors were used to unravel the S100A8/A9 secretion mechanism. The impact of S100A8/A9 to the pathophysiology of FMF was analyzed with FMF (MEFV V726A/V726A ) and S100A9 -/- mouse models. Pyrin-S100A8/A9 interaction was investigated by coimmunoprecipitation, immunofluorescence, and enzyme-linked immunosorbent assay studies., Results: The S100A8/A9 complexes directly interacted with pyrin. Knocking out pyrin, caspase-1, or gasdermin D inhibited the secretion of these S100 alarmins. Inflammatory S100A8/A9 dimers were inactivated by tetramer formation. Blocking this inactivation by targeted S100A9 deletion in a murine FMF model demonstrated the relevance of this novel autoinflammatory pathway in FMF., Conclusion: This is the first proof that members of the S100 alarmin family are released in a pyrin/caspase-1/gasdermin D-dependent pathway and directly drive autoinflammation in vivo., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Objectives: To standardly assess and describe nailfold videocapillaroscopy (NVC) assessment in children and adolescents with juvenile rheumatic and musculoskeletal diseases (jRMD) vs healthy controls (HCs)., Material and Methods: In consecutive jRMD children and matched HCs from 13 centres worldwide, 16 NVC images per patient were acquired locally and read centrally per international consensus standard evaluation of the EULAR Study Group on Microcirculation in Rheumatic Diseases. A total of 95 patients with JIA, 22 with JDM, 20 with childhood-onset SLE (cSLE), 13 with juvenile SSc (jSSc), 21 with localized scleroderma (lSc), 18 with MCTD and 20 with primary RP (PRP) were included. NVC differences between juvenile subgroups and HCs were calculated through multivariable regression analysis., Results: A total of 6474 images were assessed from 413 subjects (mean age 12.1 years, 70.9% female). The quantitative NVC characteristics were significantly lower or higher in the following subgroups compared with HCs: for density: lower in jSSc, JDM, MCTD, cSLE and lSc; for dilations: higher in jSSc, MCTD and JDM; for abnormal shapes: higher in JDM and MCTD; for haemorrhages: higher in jSSc, MCTD, JDM and cSLE. The qualitative NVC assessment of JIA, lSc and PRP did not differ from HCs, whereas the cSLE and jSSc, MCTD, JDM and cSLE subgroups showed more non-specific and scleroderma patterns, respectively., Conclusions: This analysis resulted from a pioneering registry of NVC in jRMD. The NVC assessment in jRMD differed significantly from HCs. Future prospective follow-up will further elucidate the role of NVC in jRMD., (© The Author(s) 2022. Published by Oxford University Press on behalf of the British Society for Rheumatology.)

Objective: To determine prevalence of variations of subchondral bone appearance that may mimic erosions on T1-weighted magnetic resonance imaging (MRI) of pediatric sacroiliac (SI) joints according to age and sex., Methods: With ethics committee approval and informed consent, SI joint MRIs of 251 children (132 girls), mean age 12.4 years (range 6.1-18.0 years), were obtained in 2 cohorts: 127 children imaged for nonrheumatic reasons, and 124 children with low back pain but no features of sacroiliitis at initial clinical MRI review. MRIs were reviewed by 3 experienced radiologists, blinded from each other, for 3 features of the cortical black line representing the subchondral bone plate on T1-weighted MRI: visibility, blurring, and irregularity., Results: Based on agreement from 2 or more readers, the cortical black line was partially absent in 88.4% of the children, blurred in 34.7%, and irregular in 41.4%. All these features were most common on the iliac side of SI joints and at the first sacral vertebra level. Clearly visualized, sharply delineated SI joints with none of these features were seen in only 8.0% of children, or in 35.1% if we conservatively required agreement of all 3 readers to consider a feature present. There was no significant difference between sexes or cohorts; findings were similar across pediatric age groups., Conclusion: Understanding the normal MRI appearance of the developing SI joint is necessary to distinguish physiologic findings from disease. At least two-thirds (65%) of normal pediatric SI joints showed at least 1 feature that is a component of the adult definition of SI joint erosions, risking overdiagnosis of sacroiliitis., (© 2021 American College of Rheumatology.)

Background: Transcriptome profiling of blood cells is an efficient tool to study the gene expression signatures of rheumatic diseases. This study aims to improve the early diagnosis of pediatric rheumatic diseases by investigating patients' blood gene expression and applying machine learning on the transcriptome data to develop predictive models., Methods: RNA sequencing was performed on whole blood collected from children with rheumatic diseases. Random Forest classification models were developed based on the transcriptome data of 48 rheumatic patients, 46 children with viral infection, and 35 controls to classify different disease groups. The performance of these classifiers was evaluated by leave-one-out cross-validation. Analyses of differentially expressed genes (DEG), gene ontology (GO), and interferon-stimulated gene (ISG) score were also conducted., Results: Our first classifier could differentiate pediatric rheumatic patients from controls and infection cases with high area-under-the-curve (AUC) values (AUC = 0.8 ± 0.1 and 0.7 ± 0.1, respectively). Three other classifiers could distinguish chronic recurrent multifocal osteomyelitis (CRMO), juvenile idiopathic arthritis (JIA), and interferonopathies (IFN) from control and infection cases with AUC ≥ 0.8. DEG and GO analyses reveal that the pathophysiology of CRMO, IFN, and JIA involves innate immune responses including myeloid leukocyte and granulocyte activation, neutrophil activation and degranulation. IFN is specifically mediated by antibacterial and antifungal defense responses, CRMO by cellular response to cytokine, and JIA by cellular response to chemical stimulus. IFN patients particularly had the highest mean ISG score among all disease groups., Conclusion: Our data show that blood transcriptomics combined with machine learning is a promising diagnostic tool for pediatric rheumatic diseases and may assist physicians in making data-driven and patient-specific decisions in clinical practice., (© 2022. The Author(s).)

Background: To evaluate clinical characteristics, imaging findings, therapeutic approach and outcome of paediatric patients with Chronic Non-Bacterial Osteomyelitis (CNO)., Methods: Retrospective review of 30 children diagnosed with CNO at two tertiary care centres in Belgium. Imaging data were evaluated by blinded paediatric radiologists., Results: Mean age at onset was 10.3 years and mean age at diagnosis was 11.7 years. Bone pain was the leading symptom (29/30 patients). Out of 180 symptomatic lesions, 131 were confirmed on MRI as hyperintense geographic lesions on STIR images at the metaphysis and epiphysis adjacent to growth plates of tubular bones. The most common sites of involvement were the lower limbs, spine, sternoclavicular joint and humerus. For nearly half of the patients (14/30) monotherapy with NSAIDs was sufficient to obtain remission. The remaining 16 patients received second-line therapy: bisphosphonates (n = 15/30), disease-modifying antirheumatic drugs (n = 7/30), etanercept (n = 4/30) and tocilizumab (n = 1/30). Remission was reached after a mean time of 37.6 months in 26/30 patients. The prognosis was worse for patients with spinal involvement, resulting in more long-term sequelae., Conclusions: We present a multicentre paediatric cohort of 30 CNO patients. A typical pattern of bone involvement could be found on MRI. NSAIDs were administered as first-line treatment. Second-line strategies included bisphosphonates, corticosteroids, methotrexate, etanercept and tocilizumab., Trial Registration: Retrospectively registered. Registratienummer EC KUL: MP018023., (© 2022. The Author(s).)

In rare instances, pediatric SARS-CoV-2 infection results in a novel immunodysregulation syndrome termed multisystem inflammatory syndrome in children (MIS-C). We compared MIS-C immunopathology with severe COVID-19 in adults. MIS-C does not result in pneumocyte damage but is associated with vascular endotheliitis and gastrointestinal epithelial injury. In MIS-C, the cytokine release syndrome is characterized by IFNγ and not type I interferon. Persistence of patrolling monocytes differentiates MIS-C from severe COVID-19, which is dominated by HLA-DRlo classical monocytes. IFNγ levels correlate with granzyme B production in CD16+ NK cells and TIM3 expression on CD38+/HLA-DR+ T cells. Single-cell TCR profiling reveals a skewed TCRβ repertoire enriched for TRBV11-2 and a superantigenic signature in TIM3+/CD38+/HLA-DR+ T cells. Using NicheNet, we confirm IFNγ as a central cytokine in the communication between TIM3+/CD38+/HLA-DR+ T cells, CD16+ NK cells, and patrolling monocytes. Normalization of IFNγ, loss of TIM3, quiescence of CD16+ NK cells, and contraction of patrolling monocytes upon clinical resolution highlight their potential role in MIS-C immunopathogenesis., Competing Interests: Disclosures: No disclosures were reported., (© 2021 Hoste et al.)

Background: Magnetic resonance imaging (MRI) features of active sacroiliac joint inflammation include joint space fluid and enhancement, but it is unclear to what extent these are present in normal children., Objective: To describe normal MRI appearances of pediatric sacroiliac joint spaces in boys and girls of varying ages., Materials and Methods: In this ethics-approved prospective study, 251 children (119 boys, 132 girls; mean age: 12.4 years, range: 6.1-18.0 years), had both oblique-coronal T1-weighted and short tau inversion recovery (STIR) sacroiliac joint MRI. Of these, 127 were imaged for other reasons and had asymptomatic sacroiliac joints ("normal cohort") while 124 had low back pain with no features of sacroiliitis on initial clinical MRI review ("low-back-pain cohort"). Post-gadolinium T1-weighted sequences were available in 16/127 normal and 124/124 low-back-pain subjects. Three experienced radiologists scored high signal in the sacroiliac joint space on STIR (score 0=absent; 1=high signal compared to normal bone marrow present anywhere in the joint but not as bright as fluid [compared to vessels, cerebrospinal fluid]; 2=definite fluid signal in part of the joint; 3=definite fluid signal, entire vertical height, majority of slices) and, when available, joint space post-contrast enhancement (0=no high signal/enhancement; 1=thin, symmetrical, mildly increased linear high signal present in the joint space; 2=focal, thick or intense enhancement). Associations between joint signal scores, age, gender and sacral apophyseal closure were analysed., Results: Increased signal on STIR (score 1-3) was present in 74.7% of pediatric sacroiliac joint spaces, as intense as fluid in 18.4%. There was no significant difference in proportion by gender, side or cohort, but girls showed peak signal earlier than boys (10 years old vs. 12 years old, respectively). On post-gadolinium T1-weighted sequences, a thin rim of increased signal was nearly universally seen in sacroiliac joint spaces without focal, intense or thick post-contrast enhancement., Conclusion: Sacroiliac joint spaces of most children demonstrate mildly increased signal on STIR, compared to normal bone marrow, and thin rim-like enhancement on post-contrast T1 images, likely related to cartilage. These findings should not be confused with sacroiliitis., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objectives: To determine patterns of variation of subchondral T2 signal changes in pediatric sacroiliac joints (SIJ) by location, age, sex, and sacral apophyseal closure., Methods: MRI of 502 SIJ in 251 children (132 girls), mean age 12.4 years (range 6.1-18.0), was obtained with parental informed consent. One hundred twenty-seven out of 251 had asymptomatic joints and were imaged for non-rheumatologic reasons, and 124 had low back pain but no sign of sacroiliitis on initial clinical MRI review. After calibration, three subspecialist radiologists independently scored subchondral signal changes on fat-suppressed fluid-sensitive sequences from 0 to 3 in 4 locations, and graded the degree of closure of sacral segmental apophyses. Associations between patient age, sex, signal changes, and apophyseal closure were analyzed., Results: Rim-like subchondral increased T2 signal or "flaring" was much more common at sacral than iliac SIJ margins (72% vs 16%, p < 0.001) and was symmetrical in > 90% of children. Iliac flaring scores were always lower than sacral, except for 1 child. Signal changes decreased as sacral apophyses closed, and were seen in < 20% of subjects with fully closed apophyses. Signal changes were more frequent in boys, and peaked in intensity later than for girls (ages 8-12 vs. 7-10). Subchondral signal in iliac crests was high throughout childhood and did not correlate with other locations., Conclusions: Subchondral T2 "flaring" is common at SIJ of prepubertal children and is generally sacral-predominant and symmetrical. Flaring that is asymmetrical, greater in ilium than sacrum, or intense in a teenager with closed apophyses, is unusual for normal children and raises concern for pathologic bone marrow edema., Key Points: • A rim of subchondral high T2 signal is commonly observed on MRI at pediatric sacroiliac joints, primarily on the sacral side before segmental apophyseal closure, and should not be confused with pathology. • Unlike subchondral signal changes elsewhere, high T2 signal underlying the iliac crest apophyses is a near-universal normal finding in children that usually persists throughout adolescence. • The following patterns are unusual in normal children and are suspicious for pathology: definite iliac flaring, iliac flaring more intense than sacral flaring, left-right difference in flaring, definite flaring of any pattern in teenagers after sacral apophyseal closure.

Background and Objective: Familial Mediterranean fever (FMF) is the most common monogenic autoinflammatory disease (AID) worldwide. The disease is caused by mutations in the MEFV gene encoding the inflammasome sensor Pyrin. Clinical diagnosis of FMF is complicated by overlap in symptoms with other diseases, and interpretation of genetic testing is confounded by the lack of a clear genotype-phenotype association for most of the 340 reported MEFV variants. In this study, the authors designed a functional assay and evaluated its potential in supporting FMF diagnosis., Methods: Peripheral blood mononuclear cells (PBMCs) were obtained from patients with Pyrin-associated autoinflammation with an FMF phenotype (n=43) or with autoinflammatory features not compatible with FMF (n=8), 10 asymptomatic carriers and 48 healthy donors. Sera were obtained from patients with distinct AIDs (n=10), and whole blood from a subset of patients and controls. The clinical, demographic, molecular genetic factors and other characteristics of the patient population were assessed for their impact on the diagnostic test read-out. Interleukin (IL)-1β and IL-18 levels were measured by Luminex assay., Results: The ex vivo colchicine assay may be performed on whole blood or PBMC. The functional assay robustly segregated patients with FMF from healthy controls and patients with related clinical disorders. The diagnostic test distinguished patients with classical FMF mutations (M694V, M694I, M680I, R761H) from patients with other MEFV mutations and variants (K695R, P369S, R202Q, E148Q) that are considered benign or of uncertain clinical significance., Conclusion: The ex vivo colchicine assay may support diagnosis of FMF and functional subtyping of Pyrin-associated autoinflammation., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.)

Objectives: Today, the contribution of myositis-specific autoantibodies (MSA) in the diagnostic workup of idiopathic inflammatory myopathies (IIM) is on the rise. The aim of this study was to document MSA frequency as detected by lineblot in a set of consecutive MSA requests and to correlate the results with clinical diagnosis, IIM subtype and indirect immunofluorescence (IIF) findings. Additionally, a comparison between two lineblots was performed., Methods: A total of 118 consecutive samples of patients with suspicion of IIM were analysed on IIF and two lineblots. A total of 107 patients with autoimmune rheumatic diseases served as controls., Results: MSA were detected in 55% of IIM patients (n=31) and 7.9% (n=12) of patients without clinical diagnosis of IIM or myositis overlap syndrome. All the IIM patients had a MSA-compatible clinical subtype. There was no to fair agreement between both lineblots for the individual antibodies, with most discrepancies observed for anti-TIF1γ (κ=-0.021), anti-SRP (κ=-0.006) and anti-SAE (κ=0.395). Differences between both assays were mostly observed in the non-IIM patients, also showing signi cantly lower blot signal intensities compared to IIM patients (p=0.0013). MSA in the non-IIM patients frequently showed an incompatible IIF pattern., Conclusions: Lineblot seems to be an interesting tool for MSA detection in a clinical context, allowing the identification of clinical subtypes. However, considerable caution must be exercised in interpreting the results in case of low positive MSA signal intensity, discordant lineblot results and/or an incompatible IIF pattern.

Background: Meningitis can be caused by several viruses and bacteria. Identifying the causative pathogen as quickly as possible is crucial to initiate the most optimal therapy, as acute bacterial meningitis is associated with a significant morbidity and mortality. Bacterial meningitis requires antibiotics, as opposed to enteroviral meningitis, which only requires supportive therapy. Clinical presentation is usually not sufficient to differentiate between viral and bacterial meningitis, thereby necessitating cerebrospinal fluid (CSF) analysis by PCR and/or time-consuming bacterial cultures. However, collecting CSF in children is not always feasible and a rather invasive procedure., Methods: In 12 Belgian hospitals, we obtained acute blood samples from children with signs of meningitis (49 viral and 7 bacterial cases) (aged between 3 months and 16 years). After pathogen confirmation on CSF, the patient was asked to give a convalescent sample after recovery. 3' mRNA sequencing was performed to determine differentially expressed genes (DEGs) to create a host transcriptomic profile., Results: Enteroviral meningitis cases displayed the largest upregulated fold change enrichment in type I interferon production, response and signaling pathways. Patients with bacterial meningitis showed a significant upregulation of genes related to macrophage and neutrophil activation. We found several significantly DEGs between enteroviral and bacterial meningitis. Random forest classification showed that we were able to differentiate enteroviral from bacterial meningitis with an AUC of 0.982 on held-out samples., Conclusions: Enteroviral meningitis has an innate immunity signature with type 1 interferons as key players. Our classifier, based on blood host transcriptomic profiles of different meningitis cases, is a possible strong alternative for diagnosing enteroviral meningitis.

Objective: Chronic pain is central to juvenile idiopathic arthritis (JIA) and is predictive of impaired functioning. Whereas most work has focused on identifying psychosocial risk factors for maladaptive outcomes, we explored the idea that child and parental psychological flexibility (PF) represent resilience factors for adaptive functioning of the child. We also explored differences between general vs pain-specific PF in contributing to child outcomes., Methods: Children with JIA (age eight to 18 years) and (one of) their parents were recruited at the Department of Pediatric Rheumatology at the Ghent University Hospital in Belgium. They completed questionnaires assessing child and parent general and pain-specific PF and child psychosocial and emotional functioning and disability., Results: The final sample consisted of 59 children and 48 parents. Multiple regression analyses revealed that child PF contributed to better psychosocial functioning and less negative affect. Child pain acceptance contributed to better psychosocial functioning, lower levels of disability, and lower negative affect, and also buffered the negative influence of pain intensity on disability. Bootstrap mediation analyses demonstrated that parental (general) PF indirectly contributed to child psychosocial functioning and affect via the child's (general) PF. Parent pain-specific PF was indirectly linked to child psychosocial functioning, disability, and negative affect via child pain acceptance., Conclusions: Our findings indicate that child and parental PF are resilience factors and that pain acceptance buffers the negative impact of pain intensity. Implications for psychosocial interventions that target (pain-specific) PF in children and parents are discussed., (© 2018 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: To describe the 6-year safety and efficacy of etanercept (ETN) in children with extended oligoarticular juvenile idiopathic arthritis (eoJIA), enthesitis-related arthritis (ERA), and psoriatic arthritis (PsA) METHODS: Patients who completed the 2-year, open-label, phase III CLinical Study In Pediatric Patients of Etanercept for Treatment of ERA, PsA, and Extended Oligoarthritis (CLIPPER) were allowed to enroll in its 8-year long-term extension (CLIPPER2). Children received ETN at a once-weekly dose of 0.8 mg/kg, up to a maximum dose of 50 mg/week. Efficacy assessments included the JIA core set of outcomes, the JIA American College of Rheumatology response criteria (JIA-ACR), and the Juvenile Arthritis Disease Activity Score (JADAS). Efficacy data are reported as responder analyses using a hybrid method for missing data imputation and as observed cases. Safety assessments included treatment-emergent adverse events (TEAEs)., Results: Out of 127 patients originally enrolled in CLIPPER, 109 (86%) entered CLIPPER2. After 6 years of trial participation (2 years in CLIPPER and 4 years in CLIPPER2), 41 (32%) patients were still taking ETN, 13 (11%) entered the treatment withdrawal phase after achieving low/inactive disease (of whom 7 had to restart ETN), 36 (28%) discontinued treatment for other reasons but are still being observed, and 37 (29%) discontinued treatment permanently. According to the hybrid imputation analysis, proportions of patients achieving JIA ACR90, JIA ACR100, and JADAS inactive disease after the initial 2 years of treatment were 58%, 48%, and 32%, respectively. After the additional 4 years, those proportions in patients who remained in the trial were 46%, 35%, and 24%. Most frequently reported TEAEs [n (%), events per 100 patient-years] were headache [28 (22%), 5.3], arthralgia [24 (19%), 4.6], and pyrexia [20 (16%), 3.8]. Number and frequency of TEAEs, excluding infections and injection site reactions, decreased over the 6-year period from 193 and 173.8, respectively, during year 1 to 37 and 61.3 during year 6. A single case of malignancy (Hodgkin's lymphoma) and no cases of active tuberculosis, demyelinating disorders, or deaths were reported., Conclusions: Open-label etanercept treatment for up to 6 years was safe, well tolerated, and effective in patients with eoJIA, ERA, and PsA., Trial Registration: ClinicalTrials.gov: CLIPPER, NCT00962741 , registered 20 August, 2009, CLIPPER2, NCT01421069 , registered 22 August, 2011.

Background: Arterial ischemic stroke is rare in childhood. Often, the diagnosis is made after considerable delay. A thorough workup to pinpoint the underlying etiology is necessary, as a correct diagnosis is the determining factor in treatment decision. In case of primary angiitis of the central nervous system, treatment with corticosteroids and immunosuppressive agents is indicated., Case Study: We described an eleven-year-old boy who presented at the age of six years with left hemiparesis and hemianopia. Cerebral imaging showed acute ischemia in the right posterior cerebral artery territory. Extensive workup was negative. In the following eight months, he had recurrent strokes on three separate occasions due to progressive arteriopathy involving multiple large- and medium-sized vessels. A presumed diagnosis of primary angiitis of the central nervous system was made. Pulse intravenous methylprednisolone therapy was started followed by oral prednisolone. After the fourth stroke, a six-month treatment with cyclophosphamide was given which was followed by maintenance treatment with azathioprine. Shortly after cessation of corticosteroids and cyclophosphamide the subject relapsed. Cyclophosphamide was restarted in combination with corticosteroids and subsequently replaced by mycophenolate mofetil. Under mycophenolate mofetil maintenance treatment combined with low-dose corticosteroids, the patient achieved disease control with a relapse-free period of more than four years., Conclusion: A guideline for current treatment of relapsing central nervous system angiitis in childhood is missing in the literature. We describe a subject with multiple relapses despite treatment with corticosteroids and immunosuppressive agents, and stabilization of his clinical condition and of the radiological signs under mycophenolate mofetil treatment., (Copyright © 2018 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.)

A 3-month-old boy presented with failure to thrive and a history of a prenatally detected unilateral hydroureteronephrosis which was confirmed after birth. His growth and developmental milestones had been normal during the first 2 months but in the third month his appetite was poor with reduced intake but no vomiting. At presentation, his temperature was normal, there was mild dehydration and there was weight loss (his weight had decreased by 270 g in the past month). Haemoglobin was 11.9 g/dL, total white cell count 20.2 × 10 9 /L (7-15) [neutrophils 30% (39-75) and lymphocytes 61% (16-47)], platelets 702 × 10 9 /L (150-450), BUN12.1 mmol/L (2.1-16.1), serum creatinine 35.4 μmol/L (15.0-37.1), sodium 126 mmol/L (135-144), potassium 6.8 mmol/L (3.6-4.8), chloride 88 mmol/L (98-106) and bicarbonate 14 mmol/L (19-24). Intravenous rehydration with sodium chloride 0.9% solution was commenced and he was transferred to the paediatric intensive care unit. A salt-wasting syndrome was suspected and a differential diagnosis included adrenal insufficiency, pseudohypoaldosteronism and congenital adrenal hyperplasia (owing to 21-hydroxylase deficiency). Urinalysis confirmed a urinary tract infection. Serum aldosterone was 3608 ng/dL (3.7-43.2), plasma renin activity > 38.9 pmol/L (<0.85), random cortisol 459 nmol/L (74-289), adrenocorticotropic hormone (ACTH) 6.01 pmol/L (1.32-6.60) and 17-hydroxyprogesterone 4.01 nmol/L (<3.2). Treatment of the urinary tract infection was followed by normalisation of serum electrolytes and other biochemical abnormalities, return of appetite and normal growth, which confirmed the diagnosis of transient pseudohypoaldosteronsim (TPHA). TPHA is discussed and insight provided to enable early recognition and adequate treatment of this rare clinical entity.

The Juvenile Arthritis Multidimensional Assessment Report (JAMAR) is a new parent/patient reported outcome measure that enables a thorough assessment of the disease status in children with juvenile idiopathic arthritis (JIA). We report the results of the cross-cultural adaptation and validation of the parent and patient versions of the JAMAR in the Flemish language. The reading comprehension of the questionnaire was tested in 10 JIA parents and patients. Each participating centre was asked to collect demographic, clinical data and the JAMAR in 100 consecutive JIA patients or all consecutive patients seen in a 6-month period and to administer the JAMAR to 100 healthy children and their parents. The statistical validation phase explored descriptive statistics and the psychometric issues of the JAMAR: the 3 Likert assumptions, floor/ceiling effects, internal consistency, Cronbach's alpha, interscale correlations, test-retest reliability, and construct validity (convergent and discriminant validity). A total of 100 JIA patients (8% systemic, 33% oligoarticular, 24% RF negative polyarthritis, 35% other categories) and 99 healthy children, were enrolled in two centres. The JAMAR components discriminated well healthy subjects from JIA patients. All JAMAR components revealed good psychometric performances. In conclusion, the Flemish version of the JAMAR is a valid tool for the assessment of children with JIA and is suitable for use both in routine clinical practice and clinical research.

Pediatric renal transplantation with a living donor (LD) has superior outcome, but there is a paucity of studies analyzing the reasons for not undertaking living donation in West-European countries. The aim of this study was to retrospectively review the choice of donor source in our center. We also aimed to identify factors which prevented transplantation with a LD. This retrospective study was performed including children aged 2-19 years who underwent kidney transplantation (KT) at the Ghent University Hospital between 1996 and 2016. Relevant data were collected from medical files to identify the main medical, psychological, and socio-economic factors influencing the choice of the donor source. There were 48 patients (boys n = 33) who underwent KT. Thirty-nine patients received a deceased donor (DD) kidney and nine patients received a LD kidney. Sixteen of 48 transplantations were preemptive. The reasons for DD KT included socio-economic factors such as single caregiver families, one or both parents with a criminal record or convictions and religious or cultural constraints (n = 15), medical considerations (n = 13), refusal of the close relatives/parents to donate (n = 7), and acceptance of an organ from a DD while prospective donor was undergoing medical screening (n = 4). The low incidence of living kidney donation can be explained by socio-economic and medical factors. Refusal to donate is a potentially modifiable factor and strategies aimed at education and guidance of the families might contribute to a higher incidence of living donation in our setting., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: The Assessment of Spondyloarthritis International Society (ASAS) definition for a 'positive' Magnetic Resonance Imaging (MRI) for sacroiliitis is well studied and validated in adults, but studies about the value of this definition in children are lacking. The aim of this study is to evaluate whether the adult ASAS definition of a positive MRI of the sacroiliac joints can be applied to children with a clinical suspicion of Juvenile Spondyloarthritis (JSpA)., Methods: Two pediatric musculoskeletal radiologists blinded to clinical data independently retrospectively reviewed sacroiliac (SI) joint MRI in 109 children suspected of sacroiliitis. They recorded global impression (sacroiliitis yes/no) and whether the adult ASAS definition for sacroiliitis was met at each joint. This was compared to gold-standard clinical diagnosis of JSpA. Additionally, MRI were scored according to'adapted' ASAS definitions including other features of sacroiliitis on MRI., Results: JSpA was diagnosed clinically in 47/109 (43%) patients. On MRI, sacroiliitis was diagnosed by global assessment in 30/109 patients, of whom 14 also fulfilled ASAS criteria. No patients with negative global assessment for sacroiliitis fulfilled ASAS criteria. Sensitivity (SN) for JSpA was higher for global assessment (SN = 49%) than for ASAS definition (SN = 26%), but the ASAS definition was more specific (SP = 97% vs. 89%). Modifying adult ASAS criteria to allow bone marrow edema (BME) lesions seen on only one slice, synovitis or capsulitis, increased SN to 36%, 32% and 32% respectively, only slightly lowering SP. Including structural lesions increased SN to 28%, but lowered specificity to 95%., Conclusion: The adult ASAS definition for sacroiliitis has low sensitivity in children. A pediatric-specific definition of MRI-positive sacroiliitis including BME lesions visible on one slice only, synovitis and/or capsulitis may improve diagnostic utility, and increase relevance of MRI in pediatric rheumatology practice.

Familial Mediterranean fever (FMF) is the most common monogenic autoinflammatory disease worldwide. It is caused by mutations in the inflammasome adaptor Pyrin, but how FMF mutations alter signaling in FMF patients is unknown. Herein, we establish Clostridium difficile and its enterotoxin A (TcdA) as Pyrin-activating agents and show that wild-type and FMF Pyrin are differentially controlled by microtubules. Diverse microtubule assembly inhibitors prevented Pyrin-mediated caspase-1 activation and secretion of IL-1β and IL-18 from mouse macrophages and human peripheral blood mononuclear cells (PBMCs). Remarkably, Pyrin inflammasome activation persisted upon microtubule disassembly in PBMCs of FMF patients but not in cells of patients afflicted with other autoinflammatory diseases. We further demonstrate that microtubules control Pyrin activation downstream of Pyrin dephosphorylation and that FMF mutations enable microtubule-independent assembly of apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) micrometer-sized perinuclear structures (specks). The discovery that Pyrin mutations remove the obligatory requirement for microtubules in inflammasome activation provides a conceptual framework for understanding FMF and enables immunological screening of FMF mutations., Competing Interests: H.V.G., P.H.V.S., and M.L. are listed as inventor on a patent application on immunological FMF diagnosis.

Background: The aim of the study was to analyze the incidence of hypertension in pediatric liver transplantation (LT) recipients using ambulatory blood pressure measurements (ABPM) and to identify factors associated with hypertension. We also investigated whether hypertension or tacrolimus predose concentration (TAC C0) was associated with increased left ventricular (LV) wall thickness., Patients and Methods: On a retrospective longitudinal base, we included 39 pediatric LT recipients. Median time since transplantation was 65 months (range: 11-183). Two consecutive ABPM were analyzed with a median time interval of 13 months. Data from echocardiographic evaluation parallel to the baseline ABPM were analyzed. All patients except 1 were prescribed tacrolimus. The median TAC C0 was 4 ng/mL (range 0.9-11.2). Univariate and multivariate logistic regression models were fitted to identify factors associated with systolic and diastolic hypertension and LV wall thickness., Results: Twenty-two of 39 children were hypertensive at baseline and 19 of 32 were hypertensive at follow-up. At baseline 10 (26%) children had masked systolic hypertension. TAC C0 was associated with systolic (P = 0.007, Exp(B) 2.02, 95% CI 1.2-3.3) and diastolic (P = 0.044, Exp(B) 1.48, 95% CI 1.0-2.2) hypertension. LV wall thickness was increased in children after LT compared with healthy population, but it was not associated with hypertension or TAC C0., Conclusions: Given the high prevalence of masked hypertension, ABPM should be performed in all pediatric LT recipients. Systolic and diastolic hypertension is associated with TAC C0; therefore, children with a higher target TAC C0 require a more intensive blood pressure surveillance.

Early diagnosis of spondyloarthritis (SpA) is becoming more important as new medical treatment options have become available to treat inflammation and delay progression of the disease. Increasingly, magnetic resonance imaging (MRI) of the sacroiliac joints is obtained for early detection of inflammatory changes, as it shows active inflammatory and structural lesions of sacroiliitis long before radiographic changes become evident. MRI of the sacroiliac joints in children is a useful tool for suspected juvenile spondyloarthritis (JSpA), even though it is not yet included in the current pediatric classification systems. Recognizing MRI features of pediatric sacroiliitis is a challenge. As most radiologists are not familiar with the normal MRI appearance of the pediatric sacroiliac joint, clear definitions are mandatory. Actually, the adult Assessment of Spondyloarthritis International Society (ASAS) definition for sacroiliitis needs some adaptations for children. A proposal for a possible pediatric-specific definition for active sacroiliitis on MRI is presented in this review. Furthermore, MRI without contrast administration is sufficient to identify bone marrow edema (BME), capsulitis, and retroarticular enthesitis as features of active sacroiliitis in JSpA. In selected cases, when high short tau inversion recovery (STIR) signal in the joint is the only finding, gadolinium-enhanced images may help to confirm the presence of synovitis. Lastly, we found a high correlation between pelvic enthesitis and sacroiliitis on MRI of the sacroiliac joints in children. As pelvic enthesitis indicates active inflammation, it may play a role in assessment of the inflammatory status. Therefore, it should be carefully sought and noted when examining MRI of the sacroiliac joints in children.

The aim of the study was to identify factors associated with 1,25(OH)2D3 concentrations in liver transplant recipients with emphasis on the renal function and catabolism. We also tested the hypothesis that tacrolimus increases 1,25(OH)2D3 concentrations. Serum 25(OH)D3, 1,25(OH)2D3, and 24,25(OH)2D3 were measured in 41 patients before, at 2 weeks and 3 months after transplantation. Dose-adjusted tacrolimus concentration was used as a surrogate marker of CYP3A4 activity. Factors associated with 1,25(OH)2D3 were identified using multivariate linear regression analysis. The median 1,25(OH)2D3 levels remained stable: 55 versus 46 pg/ml (P = 0.36) despite an increase in 25(OH)D3 from 18 ng/ml at baseline to 26 ng/ml (P = 0.03), serum albumin (34 to 41 g/l, P = 0.02), and comparable eGFR at baseline and month 3 (94 and 92 ml/min, respectively, P = 0.15). At 3 months 19 % of patients had 1,25(OH)2D3 < 25 pg/ml. Low eGFR and a low dose-adjusted tacrolimus concentration were both independently associated with 1,25(OH)2D3 at 3 months. Liver transplant recipients with impaired renal function or a low dose-adjusted tacrolimus concentration suggesting a high CYP3A4 are at risk of low 1,25(OH)2D3 concentrations. The use of tacrolimus does not lead to an increase in 1,25(OH)2D3 concentrations in a clinical setting.

Background: There is a growing evidence for autoimmunity in acute central nervous system (CNS) disorders and treatment with therapeutic plasma exchange (TPE) may be considered. The aim was to share our experience on the clinical application of TPE in these disorders and to present a reproducible protocol which can be used even in small children., Methods: We present a series of 8 children aged 2-12 years with transverse myelitis, Bickerstaff's brainstem encephalitis, neuromyelitis optica, and acute paraneoplastic or unspecified encephalitis in whom TPE was used as a second-line or rescue treatment., Results: A total of 104 TPE sessions were performed where 80-110 ml/kg of plasma was exchanged using 4% albumin solution and fresh frozen plasma. Six episodes of TPE-related adverse events were documented. Fibrinogen concentrations decreased after the first TPE, whereas platelets decreased gradually. One patient died in the course of the acute illness. Three children achieved a complete resolution of symptoms, 2 children have mild sequelae; whereas 2 children remain paraplegic after a follow-up of 3 to 17 months., Conclusions: We report 8 children with presumably autoimmune-mediated, acute CNS disorders treated with TPE as a rescue therapy. Although the effect of TPE can only be inferred, 5 children had a good clinical outcome. TPE is feasible even in small children with acute autoimmune CNS disorders.

Chronic recurrent multifocal osteomyelitis (CRMO) is an autoinflammatory bone disease of unknown etiology, most commonly affecting the metaphysis of long bones, especially the tibia, femur and clavicle. The clinical spectrum varies from self-limited uni-or multi-focal lesions to chronic recurrent courses. Diagnosis is based on clinical, radiologic and pathological findings, is probably underdiagnosed due to poor recognition of the disease. A dysregulated innate immunity causes immune cell infiltration of the bones with subsequent osteoclast activation leading to sterile bone lesions. The molecular pathophyiology is still incompletely understood but association with other auto-inflammatory diseases such as inflammatory bowel disease (IBD), psoriasis, Wegener's disease, arthritis and synovitis, acne, pustulosis, hyperostosis and osteitis (SAPHO) syndrome is interesting. CRMO can precede the symptoms of the associated disease by several years. The bone remodeling caused by CRMO can cause permanent disability. We report the case of a 10-year-old boy with CRMO in association with Crohn's disease., (© Acta Gastro-Enterologica Belgica.)

Objectives: Definitive sample sizes for clinical trials in rare diseases are usually infeasible. Bayesian methodology can be used to maximise what is learnt from clinical trials in these circumstances. We elicited expert prior opinion for a future Bayesian randomised controlled trial for a rare inflammatory paediatric disease, polyarteritis nodosa (MYPAN, Mycophenolate mofetil for polyarteritis nodosa)., Methods: A Bayesian prior elicitation meeting was convened. Opinion was sought on the probability that a patient in the MYPAN trial treated with cyclophosphamide would achieve disease remission within 6-months, and on the relative efficacies of mycophenolate mofetil and cyclophosphamide. Expert opinion was combined with previously unseen data from a recently completed randomised controlled trial in ANCA associated vasculitis., Results: A pan-European group of fifteen experts participated in the elicitation meeting. Consensus expert prior opinion was that the most likely rates of disease remission within 6 months on cyclophosphamide or mycophenolate mofetil were 74% and 71%, respectively. This prior opinion will now be taken forward and will be modified to formulate a Bayesian posterior opinion once the MYPAN trial data from 40 patients randomised 1:1 to either CYC or MMF become available., Conclusions: We suggest that the methodological template we propose could be applied to trial design for other rare diseases.

Objective: To investigate the efficacy and safety of etanercept (ETN) in paediatric subjects with extended oligoarticular juvenile idiopathic arthritis (eoJIA), enthesitis-related arthritis (ERA), or psoriatic arthritis (PsA)., Methods: CLIPPER is an ongoing, Phase 3b, open-label, multicentre study; the 12-week (Part 1) data are reported here. Subjects with eoJIA (2-17 years), ERA (12-17 years), or PsA (12-17 years) received ETN 0.8 mg/kg once weekly (maximum 50 mg). Primary endpoint was the percentage of subjects achieving JIA American College of Rheumatology (ACR) 30 criteria at week 12; secondary outcomes included JIA ACR 50/70/90 and inactive disease., Results: 122/127 (96.1%) subjects completed the study (mean age 11.7 years). JIA ACR 30 (95% CI) was achieved by 88.6% (81.6% to 93.6%) of subjects overall; 89.7% (78.8% to 96.1%) with eoJIA, 83.3% (67.2% to 93.6%) with ERA and 93.1% (77.2% to 99.2%) with PsA. For eoJIA, ERA, or PsA categories, the ORs of ETN vs the historical placebo data were 26.2, 15.1 and 40.7, respectively. Overall JIA ACR 50, 70, 90 and inactive disease were achieved by 81.1, 61.5, 29.8 and 12.1%, respectively. Treatment-emergent adverse events (AEs), infections, and serious AEs, were reported in 45 (35.4%), 58 (45.7%), and 4 (3.1%), subjects, respectively. Serious AEs were one case each of abdominal pain, bronchopneumonia, gastroenteritis and pyelocystitis. One subject reported herpes zoster and another varicella. No differences in safety were observed across the JIA categories., Conclusions: ETN treatment for 12 weeks was effective and well tolerated in paediatric subjects with eoJIA, ERA and PsA, with no unexpected safety findings.

Desmopressin 120 μg oral lyophilisate and 200 μg tablet are considered bioequivalent, based on extrapolation of studies in a limited number of adults and on one dose-finding study of desmopressin oral lyophilisate in children. However, no comparative pharmacokinetic study in children was executed confirming this statement. No data are available on the influence of food intake on the bioavailability of desmopressin tablet in a pediatric setting, although studies in adults have documented that food intake results in a significantly lower desmopressin plasma concentration. In this study, we analyzed plasma concentrations of desmopressin oral lyophilisate and tablet with concomitant food intake. Twenty-three children with monosymptomatic nocturnal enuresis (mean age, 12.7 years) were recruited. Two tests were performed on two separate days in identical conditions with a standardized food and fluid intake. Desmopressin was administered as desmopressin tablet or desmopressin oral lyophilisate immediately after a meal. Desmopressin plasma concentration was measured at 1 h, 2 h, and 6 h postdosing. No significant difference in plasma concentration of 120 μg desmopressin oral lyophilisate and 200 μg tablet was demonstrated, even with concomitant food intake. A significant difference in variability was found, identifying a smaller variance for desmopressin oral lyophilisate plasma concentrations at all time points. This study demonstrates comparable plasma levels for desmopressin oral lyophilisate, despite the lower dose. The dosage for desmopressin oral lyophilisate is more predictable due to the significantly smaller variance. Therefore, desmopressin oral lyophilisate seems more suitable, especially in the younger age group for which time interval between dinner and drug administration is limited.

Purpose: Complement regulators control the activated complement system. Defects in this homeostasis can result in tissue damage and autoimmune diseases with a heterogeneity in clinical presentation. Complement factor I (FI), a serine protease, is an important regulator of alternative pathway activation. We report a diagnostic work-up of a patient with relapsing inflammatory mediated meningo-encephalitis. Our work-up revealed a rare genetic factor I (FI) deficiency. So far, all cases of reported complete factor I deficiency have absent serum levels of FI. We present here a unique case of a complete factor I deficiency based on a functional FI defect., Methods: Complement assays and measurement of FI activity were performed in the patient, her family, factor H-deficient patients, a patient with C3-nephritic factor and 11 healthy controls. Genetic sequencing of the FI coding regions in the patient and her parents was performed., Results: The patient had absent alternative pathway activity with low levels of C3 and normal serum level of FI. The patient's plasma FI did not degrade C3b, with normalisation of C3b degradation after adding purified FI. Mutation analysis of the complement factor I gene revealed two heterozygous mutations (I322T and D506V)., Conclusion: To our knowledge, this paper describes a complete FI deficiency caused by a defect of FI activity for the first time. Normal FI concentration does not exclude a complete FI defect, additional functional analysis of FI is required in any patient with a defect of complement activation. Recurrent aseptic meningo-encephalitis is a rare clinical presentation of complete FI deficiency.

Purpose: With the availability of the once daily oral antimuscarinic agent solifenacin (5 mg), we started to use it for therapy resistant overactive bladder. We evaluate side effects and efficacy., Material and Methods: We reviewed the charts of children treated with solifenacin succinate between August 2005 and August 2008 for therapy resistant OAB. Incontinence was compared at study entry and study end., Results: During the study period 84 boys and 54 girls with a mean age of 9 years 2 months received solifenacin. Mean followup was 22.59 months. While on solifenacin, side effects were observed in 9 of 138 patients (6.5%). Efficacy evaluation included only 99 patients after 3 months of therapy. Mean voided volume after treatment was 253.5 ml, showing a significant 25% increase compared to the mean value before therapy (50.5 vs 203.0 ml, p <0.01). Of the patients 84 (85%) were considered responders, including 45 who were completely dry (full response) and 39 who had fewer nocturnal enuresis or diurnal incontinence symptoms (partial response). Of these 39 patients 17 became dry during the day, 1 became dry during the night and 21 had more than a 50% decrease in nocturnal enuresis and diurnal incontinence symptoms. In 15 patients the outcome was unchanged or worse (no response)., Conclusion: In this group of children with OAB we noted favorable results with solifenacin with few side effects. Despite the uncontrolled, retrospective study design the effect is attributable to solifenacin intake.

Objective: To evaluate the sensitivity and specificity of criteria designed for spondyloarthritis in a university hospital treated population of children with late onset pauciarticular juvenile chronic arthritis and a control population., Methods: Four sets of criteria especially designed for juvenile patients: Garmisch-Partenkirchen juvenile spondylitis criteria (= Garmisch), SEA (=seronegative enthesopathy and arthritis) syndrome, Enthesitis Related Arthritis (ERA), Atypical spondyloarthritis for children and two sets of criteria for patients without age specification (European spondyloarthropathy Study Group - ESSG and Amor) were evaluated in a cross-sectional way in a group of 43 consecutive patients with late onset pauciarticular juvenile chronic arthritis (LOPA) seen over a six-month period in the outpatient clinic. These criteria were analysed in 69 patients with other forms of juvenile chronic arthritis as well. The sensitivity and specificity were calculated for each set, as well as positive predictive value and likelihood ratio. The characteristics described in the different sets of criteria were separately evaluated in the LOPA patients and the other patients., Results: For sensitivity, the Garmisch criteria scored the highest value (97.7%). However, sensitivity was significantly lower in two of the juvenile sets (SEA syndrome and Atypical spondyloarthritis), respectively 44.2% and 51.2%, as opposed to the other criteria (>85%; p<0.01 by Mc Nemar test). Specificity and positive predictive value (PPV) was the highest for the SEA syndrome criteria (98.5%, vs. 95.0%) followed by the ERA (95.6 % vs. 92.1 %) and the Garmisch criteria (94.2% vs. 91.3%). The positive likelihood ratio (LR+) was >10 in SEA (30.5), ERA (18.7) and Garmisch (16.8). The negative likelihood ratio (LR-) was <0.1 only in the Garmisch criteria (0.02)., Conclusion: Sensitivity, specificity, PPV, LR+ and LR- for the Garmisch-Partenkirchen criteria suggest that they classify almost the same population as defined by LOPA. The SEA syndrome criteria, which were not designed to be classification criteria, being very specific, cannot be used in this patient population to classify a sufficient number of patients. The sensitivity and specificity for the ESSG criteria being similar in these children as in adults suggest they have similar characteristics. The Garmisch-Partenkirchen criteria and/or LOPA definition are major candidates for future research in identifying spondyloarthritis in juvenile patients.

Objective: During a study period of 4 years, 21 children are seen for night time pelvic pain. These children typical wake up in the middle of the night with severe lower abdominal or perineal pain. During day some of them suffer urge syndrome. During urodynamic investigation extremely high pelvic floor activity as recorded by high urethral pressure was observed in these children. We therefore started pelvic floor relaxation biofeedback in these children., Methods: All children diagnosed with pelvic floor spasms underwent biofeedback pelvic floor relaxation therapy in order to learn them to counteract pelvic pain due to these spasms. In those girls in whom detrusor hyperactivity was seen on urodynamics concomitant anticholinergic treatment was given (oxybutynin)., Results: Between January 1998 and January 2002 symptomatic pelvic floor spasms were diagnosed in 21 children (19 girls/2 boys). Pelvic floor relaxation biofeedback was successful for treatment of this condition in 17 of 21 children. Mean duration of therapy was 3 months (12 weekly sessions) and on long term follow-up relapse was seen in 3 of 17 successfully treated children. 10 of 17 successfully treated children received anticholinergics., Conclusion: Pelvic floor spasms in children (which can be secondary to detrusor overactivity) respond well to pelvic floor relaxation therapy.

Peritoneal dialysis (PD) solutions with amino acids (AAs) were developed as an alternative to glucose-based PD solutions for chronic renal failure. Although AA solution has many theoretical advantages, the results reported in the literature are still not convincing. Treatment of ARF is a complex problem. To tackle it, we investigated a PD solution based on a mixture of Nutrineal (Baxter Healthcare SA, Castlebar, Ireland) and Dianeal (Baxter Healthcare SA), mixed on the heating plate of the PAC Xtra cycler (Baxter Healthcare SA). The resulting solution was expected to lower the glucose load without affecting dialysis adequacy. We retrospectively analyzed data in children treated with the mixture, and evaluated safety, dialysis adequacy, acidosis, and nutritional state (albumin). Glucose reabsorption and protein losses were significantly lower when mixed AA-glucose solution was used. Despite significant AA absorption in the patients, we observed no significant difference in plasma albumin levels. Reabsorption from the dialysate of AAs varied between 21% and 69%, resulting in 27% +/- 12% of daily AA intake. Reabsorption of glucose from the dialysate was 32% - 72%. In children in intensive care, who are often already very sensitive, an AA-containing mixture may help to control glycemia, subsequently reducing the need for insulin. Our data demonstrate that the calculated percentage reabsorption of glucose and AAs is high and that AA levels in plasma remain stable. Although our data do not demonstrate a potential influence on final outcome, they demonstrate the feasibility and safety of using combined AA-glucose solution, with a calculated resorption that lends nutritional support.

The aim of peritoneal dialysis (PD) remains to deliver "appropriate" renal replacement therapy, including sufficient ultrafiltration, correction of acid-base balance, and adequate dialysis dose. We switched our pediatric patients on automated PD from standard lactate-buffered glucose solution (Dianeal: Baxter Healthcare SA, Castlebar, Ireland) to bicarbonate/lactate-buffered solution (Physioneal: Baxter Healthcare SA) as soon as it became available in our country. We also decided to deliver "optimal" dialysis in children by prescribing a long daytime dwell with icodextrin solution (Extraneal: Baxter Healthcare SA). But, adding those three benefits together--APD, Physioneal, and a long dwell with icodextrin--the result, at least in children, was a possible overcorrection of acidosis and an evolution to alkalosis. Thought must be given to developing solutions with varying bicarbonate concentrations for various treatment modalities.