Sodium removal per ultrafiltration volume in automated peritoneal dialysis in pediatric patients.

BACKGROUND: The standard rate of sodium removal in adult anuric patients on continuous ambulatory peritoneal dialysis (CAPD) is 7.5 g/L of ultrafiltration volume (UFV). Although automated PD (APD) is widely used in pediatric patients, no attempt has yet been made to estimate sodium removal in APD. METHODS: The present, retrospective cohort study included pediatric patients with APD who were managed at Tokyo Metropolitan Children's Medical Center between July 2010 and November 2017. The patients underwent a peritoneal equilibrium test (PET) at our hospital. Sodium removal per UFV was calculated by peritoneal function and dwell time using samples from patients on APD with 1- and 2-h dwell effluent within three months of PET and 4- and 10-h dwell effluent at PET. RESULTS: In total, 217 samples from 18 patients were included, with 63, 81, and 73 of the samples corresponding to the High [H], High-average [HA], and Low-average [LA] PET category, respectively. Sodium removal per UFV (g/L in salt equivalent) for dwell times of one, two, four, and ten hours was 5.2, 8.8, 8.0, and 11.5 for PET [H], 5.3, 5.8, 5.6, and 8.1 for PET [HA], and 4.6, 5.1, 5.1, and 7.1 for PET [LA], respectively. CONCLUSIONS: Sodium removal per UFV in pediatric APD was less than the standard adult CAPD and tended to be lower with shorter dwell times, leading to sodium accumulation. Therefore, salt intake should be restricted in combination with one or more long daytime dwells, especially in anuric patients.

Fractional excretion of total protein in patients with nephrotic syndrome.

BACKGROUND: The urine protein to creatinine ratio (UPCR) correlates well with the 24-h urine protein test (24-h UPT) and is a reliable indicator of proteinuria. However, in nephrotic syndrome, the correlation between the UPCR and the 24-h UPT tends to decrease. To address this, we introduced the fractional excretion of total protein (FETP), which reflects serum total protein and creatinine levels because severe hypoproteinemia and/or elevated serum creatinine levels tend to occur under these conditions. The 24-h UPT corrected for body surface area (BSA) (24-h UPT/BSA) was used to take body size into consideration. The correlation coefficients for 24-h UPT/BSA and FETP and 24-h UPT/BSA and UPCR were calculated. The statistical significance of the differences between these coefficients was also calculated. METHODS: Thirty-six pediatric patients with nephrotic syndrome were included in this study. The FETP was calculated as total protein clearance/creatinine clearance (%). Correlation coefficients were calculated for 24-h UPT/BSA and FETP and 24-h UPT/BSA and UPCR. The statistical significance of the differences between these coefficients was also calculated. RESULTS: The mean ± standard error of FETP was 0.11% ± 0.013%. The correlation coefficients of FETP and UPCR with 24-h UPT/BSA were 0.91 and 0.81, respectively. The FETP demonstrated a significantly stronger correlation with 24-h UPT/BSA than with UPCR (p = 0.01). CONCLUSIONS: The FETP correlated more strongly with 24-h UPT/BSA than with UPCR in patients with nephrotic syndrome. The FETP is a reliable indicator of proteinuria in nephrotic syndrome, especially in patients with severe hypoproteinemia or elevated serum creatinine levels.

Eculizumab for paediatric patients with atypical haemolytic uraemic syndrome: full dataset analysis of post-marketing surveillance in Japan.

BACKGROUND: Eculizumab was approved for atypical haemolytic uraemic syndrome (aHUS) in Japan in 2013. Post-marketing surveillance (PMS) was mandated by regulatory authorities to assess the safety and effectiveness of eculizumab in patients with aHUS in a real-world setting. METHODS: Paediatric patients in the PMS cohort who were <18 years of age at the first administration of eculizumab and diagnosed with aHUS [excluding Shiga toxin-producing Escherichia coli HUS, thrombotic thrombocytopaenic purpura and secondary thrombotic microangiopathy (TMA)] were included in the effectiveness and safety analysis. Clinical endpoints of effectiveness [complete TMA response, TMA event-free status, platelet (PLT) count and lactate dehydrogenase (LDH) normalization, serum creatinine (sCr) decrease and estimated glomerular filtration rate (eGFR) improvement] were analysed in patients treated with at least one dose of eculizumab. Serious adverse events (SAEs) were also evaluated. RESULTS: A total of 40 paediatric patients (median age 5 years) were included. The median eculizumab treatment duration was 66 weeks. PLT count, LDH and eGFR significantly improved at 10 days post-treatment. Complete TMA response, haematologic normalization, sCr decrease, eGFR improvement and TMA event-free status were achieved by 73.3%, 73.3%, 70.0%, 78.3% and 77.5% of patients, respectively. Discontinuation criteria were met by 18 patients: 13 patients maintained treatment discontinuation at the end of observation and 5 patients, including 1 patient with aHUS relapse, continued the treatment but extended the treatment interval. During eculizumab treatment, 59 SAEs (0.66/person-year) were reported. Although four deaths were reported, none of them were related to eculizumab. CONCLUSION: Eculizumab was well tolerated and effective for paediatric patients with aHUS in the real-world setting in Japan.

Factors related to ultrafiltration volume with icodextrin dialysate use in children.

BACKGROUND: Icodextrin has a lower absorption rate, and icodextrin peritoneal dialysate contributes to more water removal than glucose dialysate in patients with high peritoneal permeability. There are limited data on icodextrin dialysate use in children. METHODS: This study included all pediatric patients who received peritoneal equilibration tests and peritoneal dialysis with icodextrin dialysate at the study center. The factors related to ultrafiltration volume with icodextrin dialysate with long dwell time were statistically analyzed. Then the ultrafiltration volume with icodextrin and medium-concentration glucose dialysate was compared in individual cycles in the same patients. RESULTS: Thirty-six samples were included in the icodextrin group, and nine samples were used to compare the ultrafiltration volume with icodextrin and glucose dialysate. Dwell time, D/P-creatinine, D/D0-glucose, age, height, and weight correlated significantly with the ultrafiltration volume of icodextrin dialysate (p < 0.05). A dwell volume equal to or more than 550 mL/m2 was associated with a significantly higher ultrafiltration volume than a lower dwell volume (p = 0.039). Multiple regression analysis revealed that dwell time (p = 0.038) and height (p < 0.01) correlated with ultrafiltration volume significantly. In addition, the ultrafiltration volume was superior (p < 0.01), and dwell time was longer (p = 0.02), with icodextrin dialysate than with medium-concentration glucose dialysate. CONCLUSIONS: The ultrafiltration volume with icodextrin dialysate decreases in patients with small stature. Providing sufficient dwell time and volume is important for maximal water removal even in children. Ultrafiltration volume is superior with icodextrin than medium-concentration glucose dialysate for long dwell times. A higher resolution version of the Graphical abstract is available as Supplementary information.

Technical requirements and devices available for long-term hemodialysis in children-mind the gap!

Children requiring long-term kidney replacement therapy are a "rare disease" cohort. While the basic technical requirements for hemodialysis (HD) are similar in children and adults, key aspects of the child's cardiovascular anatomy and hemodynamic specifications must be considered. In this article, we describe the technical requirements for long-term HD therapy for children and the devices that are currently available around the world. We highlight the characteristics and major technical shortcomings of permanent central venous catheters, dialyzers, dialysis machines, and software available to clinicians who care for children. We show that currently available HD machines are not equipped with appropriately small circuits and sensitive control mechanisms to perform safe and effective HD in the youngest patients. Manufacturers limit their liability, and health regulatory agencies permit the use of devices, only in children according to the manufacturers' pre-specified weight limitations. Although registries show that 6-23% of children starting long-term HD weigh less than 15 kg, currently, there is only one long-term HD device that is cleared for use in children weighing 10 to 15 kg and none is available and labelled for use in children weighing less than 10 kg anywhere in the world. Thus, many children are being treated "off-label" and are subject to interventions delivered by medical devices that lack pediatric safety and efficacy data. Moreover, recent improvements in dialysis technology offered to adult patients are denied to most children. We, in turn, advocate for concerted action by pediatric nephrologists, industry, and health regulatory agencies to increase the development of dedicated HD machines and equipment for children.

Viral loads of parainfluenza virus type 3 and severity of respiratory diseases in children.

BACKGROUND: Parainfluenza virus type 3 (PIV-3) is one of the common pathogens for respiratory infections in children. Whether viral load of PIV-3 is associated with severity of respiratory diseases in children is not yet known. Our aim was to determine significance of PIV-3 viral load among infected children. METHODS: We conducted a single-center, retrospective study at Tokyo Metropolitan. Children's Medical Center, Japan, from June to August 2021. Hospitalized children were screened with a posterior nasal swab for multiplex PCR, and viral load was subsequently measured from remained samples by real-time PCR. Demographic data were collected from digital charts. PIV-3 positive patients were categorized into mild group with no oxygen demand, moderate group with low-flow oxygen demand and severe group with high-flow nasal cannula oxygen or non-invasive positive pressure ventilation or mechanical ventilation. Viral loads were compared among mild, moderate and severe groups. RESULTS: 151 patients were positive for PIV-3. We found no statistically significant association among PIV-3 viral load and severity of respiratory diseases (p = 0.35), and no statistically significant association between severity of illness and co-detection of other viruses. In each severity group, relatively high viral load per posterior nasal swab was observed at the time of testing. CONCLUSION: Among PIV-3 patients, we could not find statistically significant between viral load and their severity, therefore we could not conclude that viral load is a good surrogate marker for clinical severity of PIV-3.

Clinical implications of gallbladder enlargement in Kawasaki disease.

BACKGROUND: Kawasaki disease (KD) presents with gallbladder enlargement (GBE) or hydrops in the acute phase. Although GBE is highly specific to KD, epidemiological data on GBE have not been updated. In this study we evaluated the occurrence rate of GBE in KD and characterized the clinical features of patients who developed GBE. METHODS: The present study was a prospective, observational study. The maximum longitudinal area of the gallbladder and the common bile duct diameter in KD patients were measured by ultrasonography at the start of initial intravenous immunoglobulin (IVIG) therapy (day 0) and on days 7, 30, and 60 of therapy. The primary outcome was the complication rate of GBE (z- score ≥2.0) on day 0. The secondary outcome was the association of GBE with cholestasis, unresponsiveness to IVIG, and coronary artery lesions (CAL). RESULTS: Gallbladder enlargement occurred in 35% (35/101) of patients on day 0. Cholestasis and severe patients (Kobayashi score [KS] ≥5) were more common in the GBE group (20.6% vs. 1.6%, p = 0.002, and 54.3% vs. 15.2%, p < 0.001, respectively). In patients with a KS of ≤4, the non-responder rate was higher in the GBE group (44% vs. 20%, p = 0.0495) but did not differ in those with a KS of ≥5 (21% vs. 20%, p = 0.95). The rate of CAL occurrence did not differ significantly between the groups (8.6% vs. 6.1%, p = 0.64). CONCLUSIONS: Gallbladder enlargement occurred in 35% of KD patients and was associated with cholestasis. Gallbladder enlargement may not only be a diagnostic finding, but also a severity marker in KD patients.

Efficacy, safety, and economic impact of diazepam suppositories with as-needed acetaminophen for prevention of seizure recurrence during the same fever episode in children with suspected simple febrile seizures.

OBJECTIVE: This study was undertaken to evaluate the efficacy, safety, and economic impact of diazepam suppositories with as-needed acetaminophen in comparison with as-needed acetaminophen alone for prevention of seizure recurrence during the same fever episode in suspected pediatric simple febrile seizures (SFS). METHODS: This single-center, prospective, observational study was conducted from July 29, 2019 to February 15, 2021 at a children's hospital. Children aged 6 months to 60 months presenting to the emergency department with suspected SFS were included. Participants receiving both diazepam suppositories and as-needed acetaminophen were compared with those receiving as-needed acetaminophen alone. The primary outcome was seizure recurrence during the same fever episode. The secondary outcomes included the incidence of central nervous system (CNS) pathologies, adverse events, and medical costs. RESULTS: Of the 316 participants, 228 (72.2%) had their first febrile seizure. Diazepam (.3-.5 mg/kg for up to two doses) was administered to 88 of 316 patients (27.8%). The outcomes were available for 306 patients. The recurrence rate was 3.5% (3/85) in the patients receiving diazepam with as-needed acetaminophen and 12.2% (27/221) in the patients receiving as-needed acetaminophen alone (relative risk = .29, 95% confidence interval [CI] = .09-.93, p = .03). The adjusted odds ratio of diazepam administration against recurrence was .23 (95% CI = .07-.78, p = .02). None of the patients had a CNS pathology. No severe adverse events occurred, although mild ataxia was observed significantly more often in the patients receiving diazepam and as-needed acetaminophen (29.4% vs. 18.7%, p = .04). The median medical cost was US $199 (interquartile range [IQR] = 86-244) for the group receiving both medications and US $202 (IQR = 114-242) for the group receiving as-needed acetaminophen alone. SIGNIFICANCE: Compared with as-needed acetaminophen alone, diazepam with as-needed acetaminophen may reduce seizure recurrence more during the same fever episode without severe adverse events or additional costs in children with suspected SFS.

Response to steroid and immunosuppressive therapies may predict post-transplant recurrence of steroid-resistant nephrotic syndrome.

BACKGROUND: Recurrence of SRNS is a major challenge in KT. Several clinical factors, including initial steroid sensitivity, have been associated with increased post-transplant SRNS recurrence risk. However, conflicting data have been reported, possibly due to the heterogeneous pathophysiology of SRNS and the lack of genetic testing of SRNS patients. Furthermore, the response to immunosuppressive therapies has not been evaluated. METHODS: Seventy patients aged 1-15 years at SRNS onset who underwent KT between 2002 and 2018 were enrolled. Patients with secondary, familial, syndromic, and genetic forms of SRNS and those who were not treated with steroid were excluded. This study aimed to assess the risk factors for post-transplant recurrence, including treatment responses to initial steroid therapy and additional therapies with immunosuppressive agents, rituximab, plasmapheresis, and/or LDL-A. RESULTS: Data from 36 kidney transplant recipients were analyzed. Twenty-two (61%) patients experienced post-transplant SRNS recurrence, while 14 patients did not. The proportion of patients who achieved complete or partial remission with initial steroid therapy and/or additional therapies with immunosuppressive agents, rituximab, plasmapheresis, and/or LDL-A was significantly higher in the SRNS recurrence group (19/22, 86%) than in the group without SRNS recurrence (6/14, 43%; p = .01). CONCLUSION: This study suggests that the response to steroid treatment, other immunosuppressive agents, rituximab, plasmapheresis, and/or LDL-A may predict post-transplant SRNS recurrence.

Incidence of malignancy after pediatric kidney transplantation: a single-center experience over the past three decades in Japan.

BACKGROUND: Malignancy after kidney transplantation (KT) is one of the most serious post-transplant complications. This study aimed to investigate the incidence, type, and outcomes of malignancy after pediatric KT. METHODS: We performed a retrospective cohort study on pediatric kidney transplant recipients aged 18 years or younger who received their first transplant between 1975 and 2009. RESULTS: Among the 375 children who underwent KT, 212 were male (56.5%) and 163 were female (43.5%) (median age at KT, 9.6 years [interquartile range {IQR}] 5.8-12.9 years). The incidence of malignancy was 5.6% (n = 21). The cumulative incidences of cancer were 0.8%, 2.5%, 2.8%, 4.2%, 5.5%, and 15.6% at 1, 5, 10, 15, 20, and 30 years post-transplantation, respectively. Of 375 patients, 12 (3.2%) had solid cancer and nine (2.4%) had lymphoproliferative malignancy. The median age at the first malignancy was 21.3 years (IQR 11.5-33.3 years). The median times from transplant to diagnosis were 22.3 years (IQR 12.3-26.6 years) for solid cancer and 2.2 years (IQR 0.6-2.8) for lymphoproliferative malignancies. During follow-up, five recipients died due to malignancy. The causes of death were hepatocellular carcinoma in one patient, squamous cell carcinoma in the transplanted kidney in one patient, malignant schwannoma in one patient, and Epstein-Barr virus-related lymphoma in two patients. The mortality rate was 0.79 per 1000 person-years (95% confidence interval 0.38, 1.85). CONCLUSIONS: Early diagnosis and treatment of malignancies in transplant recipients is an important challenge. Therefore, enhanced surveillance and continued vigilance for malignancy following KT are necessary.

Half of children with IgA vasculitis-associated nephritis with nephrotic state spontaneously recover.

BACKGROUND: The clinical spectrum of Henoch-Schönlein purpura nephritis (HSPN), now known as IgA vasculitis-associated nephritis (IgAVN), ranges from isolated microscopic haematuria to nephrotic syndrome, progressive glomerulonephritis, and kidney failure. The outcome also varies, and the management of IgAVN is controversial. The presence of nephrotic state at disease onset is thought to be a risk factor of a poor prognosis. However, not all patients with nephrotic state have a poor prognosis, and it is unclear whether they need early treatment. METHODS: We herein retrospectively examined the clinical course of paediatric IgAVN cases with nephrotic state (serum albumin [sAlb]<3.0 g/dL and urine protein-creatinine ratio of >2.0 g/ gCr) without kidney injury treated at our hospital between 2010 and 2018. RESULTS: Of the 216 patients with IgAVN identified, 17 met the inclusion criteria. The median follow-up period from disease onset to the last observation was 40.5 months (IQR:31.0-74.2). Eleven patients were male, the median age at onset was 5 years, the minimum serum Alb level was 1.9 g/dL, the maximum proteinuria value was 12.3 g/gCr, and the median minimum eGFR was 86.0 mL/min/1.73 m2 in the acute phase. Eight patients (47%) achieved resolution of nephrotic state within 3 months and complete remission without treatment by the last observation. The patients with spontaneous resolution of nephrotic state had less severe hypoalbuminaemia (Alb<2.0 g/dL) and tended to show a quick increase in the serum albumin level. CONCLUSIONS: Our study found that half of paediatric patients with IgAVN with nephrotic state achieved spontaneous resolution without treatment and enjoyed a favourable short-term outcome. Consideration of the duration of nephrotic state and trends in the serum albumin level in children with IgAVN may allow unnecessary kidney biopsies and immunosuppressive therapy to be avoided.

Pediatric emergency healthcare utilization during the coronavirus disease 2019 pandemic in Tokyo.

BACKGROUND: Various public health interventions have been implemented against the coronavirus disease 2019 pandemic. We investigated changes in pediatric emergency healthcare utilization during the current pandemic. METHODS: Based on data on outpatient healthcare visits to one pediatric emergency department in Tokyo, Japan, the descriptive, cross-sectional study compared the number of emergency department visits in 2020 to the number in the previous 3 years. Data were extracted from the electronic triage reporting system. The primary outcome was the number of emergency department visits. The characteristics of patients by age group were also investigated. RESULTS: A 40.6% reduction in pediatric emergency healthcare utilization was observed during the study period, with the greatest decrease occurring in the number of visits for fever. However, while the number of patients with a complaint with an exogenous cause decreased, the proportion of these patients increased. Although social activities in the greater community have now almost normalized, and only a slight increase in the number of patients with fever has been reported, the number of emergency department visits remains lower than in previous years as of this writing. CONCLUSIONS: Public health interventions led to a reduction in emergency department visits, thereby allowing time to redistribute health-care resources.

Oxygen saturation targets in pediatric respiratory disease.

BACKGROUND: The present study aimed to assess the appropriate oxygen saturation target in patients with pediatric respiratory diseases by lowering the oxygen saturation target from SpO2 94% to 90%. No previous study has explored appropriate oxygen saturation targets in respiratory diseases other than bronchiolitis. METHODS: The present, prospective, single-arm intervention trial enrolled pediatric inpatients with bronchiolitis, bronchitis, pneumonia, and asthma. The oxygen saturation target was lowered from SpO2 94% to 90% after the patients' general condition improved. The patients continued to be observed for 12 h after achieving SpO2 94%. The duration from the first cut-off point (SpO2 90% for 12 h without oxygen) to the second cut-off point (SpO2 94% for 12 h) was then evaluated. RESULTS: In total, 248 patients completed the study. Patients with bronchiolitis, bronchitis, pneumonia, and asthma had an interval between the two cut-off points of 23.9, 15.5, 19.1, and 13.8 h, respectively, (mean 17.2 h; 95% confidence interval 15.0-19.5). CONCLUSIONS: In generally healthy children, setting the oxygen saturation target at SpO2 90% after confirming improvement in their general condition was safe. The time required for increasing SpO2 from 90% to 94% was longest in the patients with bronchiolitis.

Successful High-dose Chemotherapy in Combination With Autologous Peripheral Blood Stem Cell Transplantation in an Anuric Child With Neuroblastoma.

No reports describe high-dose chemotherapy (HDCT) with autologous peripheral blood stem cell transplantation (auto-PBSCT) in pediatric patients with neuroblastoma and end-stage renal disease. Here, we report the case of a patient with high-risk neuroblastoma who developed anuria during treatment. HDCT with auto-PBSCT under hemodialysis, with strict attention to the ultrafiltration volume and dose modification of alkylating agents, was performed. Although the first auto-PBSCT led to engraftment failure, the second auto-PBSCT resulted in successful myeloid engraftment 8 months after anuria. This case demonstrated that HDCT with auto-PBSCT can be safely performed in children with renal failure under hemodialysis.

Clinical and histological features in pediatric and adolescent/young adult patients with renal disease: a cross-sectional analysis of the Japan Renal Biopsy Registry (J-RBR).

BACKGROUND: Only a few studies have investigated epidemiological and clinicopathological information regarding pediatric and adolescent and young adult (AYA) patients with renal disease. The purpose of this study was to clarify the differences and relationship of clinicopathological findings between pediatric and AYA patients using the Japan Renal Biopsy Registry (J-RBR). METHODS: This cross-sectional study analyzed data from patients registered in the J-RBR between 2007 and 2017. Clinicopathological findings at diagnosis were analyzed for 3,463 pediatric (age < 15 years) and 6,532 AYA (age 15-30 years) patients. RESULTS: Although chronic nephritic syndrome was the most common clinical diagnosis at age > 5 years, nephrotic syndrome was the most frequent diagnosis at age < 4 years. The most common pathological diagnosis as classified by pathogenesis in pediatric patients was primary glomerular disease (except IgA nephropathy), whereas IgA nephropathy was increased in AYA patients. Mesangial proliferative glomerulonephritis was the most common pathological diagnosis as classified by histopathology in both pediatric and AYA patients. Minor glomerular abnormalities were the most frequent histopathologic diagnoses of nephrotic syndrome in childhood, but their frequency decreased with age. CONCLUSION: To the best of our knowledge, this is the first report of clinicopathological features of pediatric and AYA patients in a large nationwide registry of renal biopsy. There were differences of clinical, pathological and histopathologic findings between pediatric and AYA patients.

Risk factors of bacteremia in children hospitalized with community-acquired pneumonia: A nested case-control study.

OBJECTIVE: To assess the risk factors of bacteremia in children hospitalized with community-acquired pneumonia (CAP). STUDY DESIGN: The present, nested, case-control study enrolled a cohort of patients with CAP aged < 18 years who were hospitalized at Tokyo Metropolitan Children's Medical Center or Tama-Hokubu Medical Center between March 2010 and February 2018. Among the cohort with blood cultures (BCs), patients with bacteremia were identified and matched with five control patients based on their treatment facility, underlying disease, and age. Conditional logistic regression was used to calculate the odds ratios (ORs) of bacteremia for risk factor candidates. RESULTS: BCs were obtained for 2,383 (84%) of the 2,853 patients in the CAP cohort. Of those with BCs, 34 (1.4%) had bacteremia. S. pneumoniae and H. influenzae accounted for 26 (76%) and four (12%) instances of the bacteremia pathogens, respectively. Bacteremia occurred more frequently among patients hospitalized in the spring than during other seasons (P = 0.022). On multivariate analysis, the severity of pneumonia was not associated with bacteremia incidence (OR: 0.92 [0.30-2.85]) while a white blood cell count > 16,000/µL (OR: 5.90 [2.14-16.3]) was shown to be a significant risk factor. The OR of the need for a ventilator on admission day was significantly high (28.4 [3.02-1374]) on univariate analysis, but the subject pool was too small to determine its significance on multivariate analysis. CONCLUSIONS: The results of the present study supported BC collection in patients with leukocytosis and in those requiring ventilator use on admission.

Mean of creatinine clearance and urea clearance examined over 1 h estimates glomerular filtration rate accurately and precisely in children.

AIM: Accurate and precise estimation of glomerular filtration rate (GFR) is essential in kidney disease. We evaluated the usefulness of the mean of creatinine clearance (CCr ) and urea clearance (CUN ) examined over a 1-h urine collection period (1-h (CCr + CUN )/2) in a retrospective, cross-sectional study across two centres, as a relatively simple method for estimating GFR in children. METHODS: Children aged ≤18 years who underwent inulin clearance (CIn ) tests were eligible. Two clearance values were obtained during a 2-h test consisting of two periods of 1 h each. The mean clearance in two periods was defined as 1-h clearance. 1-h (CCr + CUN )/2, 1-h CCr , 1-h CUN and GFR estimated by Cr-based and cystatin C (CysC)-based formulas for Japanese children were compared with CIn . Bland-Altman plots were used to evaluate correlations. The primary outcome measure was the correlation between 1-h (CCr + CUN )/2 and CIn . RESULTS: Fifty-three children were analysed. Their median age was 10.9 (interquartile range [IQR] 5.3-14.2) years, and median CIn and 1-h (CCr + CUN )/2 were 77.0 (IQR: 51.5-95.1) and 81.0 (IQR: 64.1-97.7) ml/min/1.73 m2 , respectively. Percentage difference of CIn and 1-h (CCr + CUN )/2 in the Bland-Altman plot was -11.2% (95% confidence interval - 15.3% - -7.1%), with 95% lower and upper limits of agreement of -40.3% and 18.0%, respectively. Thus, 1-h (CCr + CUN )/2 was 1.12 times CIn . CONCLUSION: 1 h (CCr + CUN )/2 was almost concordant with CIn . 1-h (CCr + CUN )/2 can estimate GFR accurately and precisely, making it a simple and speedy test for use in clinical practice.

Contradiction between genetic analysis and diuretic loading test in type I Bartter syndrome: a case report.

BACKGROUND: In typical cases of Bartter syndrome (BS), assessing response to diuretics (furosemide and thiazide), hereinafter referred to as diuretic loading test, may be used to diagnose the type by detecting which part of the kidney tubule is not functioning correctly. However, the diuretic loading test may not always agree with the results of genetic analyses. CASE PRESENTATION: A 5-year-old boy was admitted due to lower extremity weakness and abnormal gait. He had a recurrent episode of muscle weakness and laboratory results showed severe hypokalemia. The direct genomic sequencing of the case revealed a new mutation in the SLC12A1 gene, which is associated with type I Bartter syndrome. Because there was the difference between the phenotype and genotype, we conducted a diuretic loading test to confirm the diagnosis. However, the results showed a clear increase in urine excretion of Na and Cl. These results were not consistent with typical type I BS, but consistent with the patient's phenotype. CONCLUSION: The diuretic loading test has limited utility for diagnosis especially in atypical cases. On the other hand, this test, which allows assessment of channel function, is useful for better understanding of the genotype-phenotype correlation.

A nationwide questionnaire survey on accidental magnet ingestion in children in Japan.

AIM: The aim is to investigate the actual situation of accidental ingestion of magnets in children in Japan and the clinical features of the resulting gastrointestinal damage. METHODS: We developed a questionnaire and sent it to 496 board-certified training hospitals nationwide. Information was collected on the number of children with accidental magnet intake from 2015 to 2017, witnesses of magnet intake, number and type of magnets, presence or absence of gastrointestinal injury, treatment, etc RESULTS: The number of cases of accidental ingestion of magnets within the study period was 104, with a median age of 2 years. About half of the incidents were unwitnessed. There were 33 cases of accidental ingestion of multiple magnets. Among them, oesophagogastroduodenoscopy was performed in 4 children and surgery in 10, and significantly invasive treatment was required in comparison with single-magnet ingestion. Gastrointestinal injury was observed in 11 cases, 10 of which were caused by multiple-magnet ingestion. All 10 of these patients underwent surgical treatment. There was no mortality. CONCLUSION: The incidence of accidental magnet ingestion in Japan is estimated to be 50-70 per year. Unwitnessed cases are not uncommon. Multiple magnet ingestion often causes gastrointestinal injury. Many cases of gastrointestinal injury are caused by ingestion of magnetic toys.

Hospitalisations due to respiratory syncytial virus infection in children with Down syndrome before and after palivizumab recommendation in Japan.

AIM: Down syndrome has been considered an independent risk factor for respiratory syncytial virus (RSV) infection. Palivizumab, an anti-RSV humanised monoclonal antibody, was currently approved for all children with Down syndrome in Japan. To investigate the change in RSV-associated hospitalisation (RSVH) rates before and after the universal approval of palivizumab in Japan in 2013, we conducted a nationwide retrospective survey. METHODS: We conducted a nationwide, retrospective, questionnaire survey across paediatric institutions in Japan. The recruited children with Down syndrome were divided into two groups: those born April 2010 to March 2013 (2010-2012 cohort) and those born April 2013 to March 2016 (2013-2015 cohort). RESULTS: Of the 664 institutions, 321 (48.3%) replied, and a total of 3929 children with Down syndrome were registered. The percentage of children who received palivizumab increased from 49.2% to 82.2%. The cumulative RSVH rate showed a decreased trend in the 2013-2015 cohort (OR, 0.83; 95%CI, 0.63-1.10), while the rate of these children (without CHD and born at a gestational age ≥ 36 weeks) was significantly decreased in the 2013-2015 cohort (OR, 0.56; 95%CI, 0.34-0.92). CONCLUSION: The cumulative RSVH rate tended to be decreased after approval for all children with Down syndrome although the result was not significant.