Pediatric early-phase anorexia nervosa without hypokalemia exhibiting acute tubular injury: a case report.

Anorexia nervosa can lead to kidney complications. Few studies reported kidney biopsy results in young adults, most of whom had chronic anorexia nervosa, and kidney biopsy findings in pediatric patients with early-phase anorexia nervosa are rarely reported. A 14-year-old girl who lost weight due to excessive exercise and reduced diet was admitted for kidney dysfunction. She was 147 cm tall and weighed 32.9 kg, with a body mass index of 15.2 kg/m2. She was 39 kg about a year earlier. Her heart rate and blood pressure were 30-40 beats/min and 108/68 mmHg, respectively. She had kidney dysfunction (estimated glomerular filtration rate, 56.6 mL/min/1.73 m2). Urine ß2-microglobulin was slightly elevated (393 µg/L), and percent tubular phosphate reabsorption was low (75.2%), suggesting tubular damage; however, hypokalemia was absent. Kidney dysfunction did not improve with fluid loading. Kidney biopsy revealed that all glomeruli were intact, with no vasculitis, interstitial inflammation or fibrosis on light microscopy. However, proximal tubular epithelial walls were flattened and the brush border was absent, suggesting acute tubular injury. Immunofluorescent staining was negative for immunoglobulins and complement proteins, and electron microscopy showed no significant electron-dense deposition. The patient's serum creatinine gradually declined, normalizing on the 17th day of admission. Unlike previous reports in young adults, kidney dysfunction was observed even in the absence of hypokalemia in the current pediatric patient with early-phase anorexia nervosa. Proximal tubular injury in early-phase anorexia nervosa may be caused by bradycardia without hypokalemia, leading to subsequent kidney dysfunction.

Delayed diagnosis and exacerbation of hyperlipidemia in idiopathic nephrotic syndrome in children during the COVID-19 pandemic.

BACKGROUND: During the coronavirus disease-2019 (COVID-19) pandemic, there was a lack of access to outpatient facilities for other diseases. Conversely, few studies have reported changes in clinical features of idiopathic nephrotic syndrome (INS) in children before and after the COVID-19 pandemic. METHODS: Thirty-two children with primary INS, who were admitted to four Showa University-affiliated hospitals between January 2017 and December 2022, were enrolled in this retrospective study. Children were divided according to the onset of INS into a post-COVID-19 group (onset in 2020-2022, n = 25) and a pre-COVID-19 group (onset in 2017-2019, n = 32). We compared the clinical characteristics and features of initial INS between two groups. RESULTS: In the post-COVID-19 group, these patients had interval between noticing symptoms of INS, such as edema and INS diagnosis was significantly longer (7 days versus 3.5 days; p = 0.0047), and had significantly raised serum LDL cholesterol levels at the time of INS diagnosis than in the pre-COVID-19 group (314 mg/dL versus 260 mg/dL; p = 0.028). Likewise, steroid-resistant nephrotic syndrome was significantly more common in the post-COVID-19 group [32% (n = 8) versus 6% (n = 2); p = 0.016]. A correlation analysis revealed a moderate positive correlation between the interval from symptom to diagnosis and LDL cholesterol (r = 0.460015, p = 0.0003). CONCLUSIONS: Children with INS after the COVID-19 pandemic showed a longer time between noticing symptoms of INS and diagnosis, increased serum LDL cholesterol and more steroid resistance than before the pandemic.

Outcomes of discontinuing renin-angiotensin system inhibitors: a study protocol for conducting systematic review and meta-analysis.

INTRODUCTION: Renin-angiotensin system (RAS) plays a key role in various types of cardiovascular disease and many kinds of RAS inhibitors have been developed. The effect of discontinuation of RAS inhibitors on clinical outcomes is still controversial. This study aims to evaluate the effects of discontinuing RAS inhibitor medication on the clinical outcomes of patients continuously taking these agents. METHODS AND ANALYSIS: This article presents a systematic review protocol described in accordance with Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols guidelines. We will include randomised controlled trials in which the effects of RAS inhibitor withdrawal were evaluated. Initially, four authors will search for eligible studies in MEDLINE, EMBASE, the Cochrane Database Trial Register, European trial registry and ClinicalTrials.gov. Abstracts and full-text screenings will be performed by the four authors with data extraction performed by each author independently. We will include patients taking RAS inhibitors-including ACE inhibitor, angiotensin receptor blocker and angiotensin receptor neprilysin inhibitor and exclude the patients undergoing renal replacement therapy (RRT), adolescents (under 18 years of age) and patients with acute infectious diseases. Our search will be performed on 1 May 2023. Studies in which the patients discontinued RAS inhibitors due to any reason will be included. Patients who continuously took RAS inhibitors under conditions in which the intervention group discontinued these agents will be considered eligible as the comparison group. Death (any cause), Death (cardiovascular disease (CVD)) and CVD events will be set as primary outcomes. Secondary outcomes will be set as RRT, acute kidney injury, renal function (analysis of the change in estimated glomerular filtration rate), hyperkalaemia, proteinuria and blood pressure. ETHICS AND DISSEMINATION: Research ethics approval was not required in this study due to it being a systematic review, and any data belonging to individuals cannot be identified. The results of this study will be disseminated through peer-reviewed journals and conferences. TRIAL REGISTRATION NUMBER: PROSPERO CRD42022300777.

Differences in the Clinical Characteristics of Kawasaki Disease Between Older and Younger Children (2015-2019): A Single-Center, Retrospective Study.

OBJECTIVE: The objective of this study was to investigate the differences in the clinical characteristics of Kawasaki disease between older and younger children. STUDY DESIGN: This retrospective study examined 405 children with Kawasaki disease admitted to Showa University Northern Yokohama Hospital between 2015 and 2019. RESULTS: Eligible patients were classified into the older (≥3.0 years of age, n = 169) and younger (<3.0 years of age, n = 236) groups. Skin rash was found in significantly fewer cases (112 [66.3%] vs 229 [97.0%], P < .001 in the younger group). Cervical lymphadenopathy was more common in older children (153 [90.5%] vs 165 [69.9%], P < .001) and in incomplete Kawasaki disease (3 or 4 findings) (34 [20.1%] vs 25 [10.6%], P = .0078). The diagnosis was more delayed in older children (median: 5.0 days vs 4.0 days, P = .003) than the younger group. Additionally, fever nonresponsive to a single intravenous immunoglobulin was more common, and the duration of fever was significantly longer in the older group (48 [28.4%] vs 47 [19.9%], P = .0479). CONCLUSIONS: Kawasaki disease should be suspected in children aged >3.0 years with cervical lymphadenopathy and fever, despite the absence of skin rash. Additionally, incomplete Kawasaki disease, fever unresolved by a single intravenous immunoglobulin infusion, and the tendency to delay treatment initiation are more common in children aged >3.0 years.

Sleep features of nocturnal enuresis: relationship between rapid eye movement sleep latency prolongation and nocturnal enuresis.

Nocturnal enuresis, or bed wetting, is the involuntary urination during sleep. One of its causes is difficulty awakening during sleep, suggesting a relationship between Nocturnal enuresis (NE) and sleep. However, no studies have yet clarified the relationship between NE and sleep, and the effects of sleep structure in NE children are not yet known. Assuming that changes in sleep structure are related to NE, there would be a difference in sleep structure between days with and without NE. We measured the sleep electroencephalograms of 27 at home patients aged 6-16 years, evaluated the differences between days with and without NE, and examined the NE-associated sleep characteristics associated. The evaluation items were total sleep time, sleep efficiency, the ratio of rapid eye movement (REM) to non-REM sleep, REM sleep latency, and non-REM sleep latency. Factors influencing NE were examined by logistic regression analysis, with NE presence/absence as the dependent variable and each evaluation item as the independent variable. Given that 2-6 measurements were made for each patient, Generalized Estimating Equations was used in the analysis. NE positively correlated with prolonged REM sleep latency, but no significant differences were found in other sleep structures. A positive correlation exists between NE and prolonged REM sleep latency. Changes in sleep structure in the early stages of sleep may lead to increased nocturnal urine volume and increased NE frequency.

Comparison of wireless and wired alarm devices for nocturnal enuresis treatment.

BACKGROUND: In monosymptomatic nocturnal enuresis (MNE) treatment, enuretic alarm devices are the first recommended treatment option. This study aimed to compare retrospectively the effectiveness of wearable wireless and wired alarm devices for MNE treatment in children aged 6-14 years. METHODS: All children aged 6-16 with MNE who underwent alarm therapy as outpatients were included. A wired alarm device was used from 2012 to 2015, and a wireless alarm device was used from 2016 to 2019. The primary outcomes were the dropout rates during therapy and at last follow up. The full response(14 consecutive dry nights) and the partial response rate during therapy were also assessed. RESULTS: Of the 173 patients enrolled, 75 and 98 used a wired and a wireless alarm device, respectively. The dropout rate at the last visit was significantly lower in the wireless alarm group than that in the wired alarm group (6.1% vs. 20.0%; P = 0.006). The full response(FR) rate was significantly higher in the wireless alarm group than these in the wired alarm group at 4, 12, 24 weeks (4 weeks: 11.2% vs. 1.3%, P = 0.011; 12 weeks: 31.9% vs. 13.5%, P = 0.005; 24 weeks: 72.9% vs. 39.7%, P < 0.0001). CONCLUSIONS: Wireless alarm therapy for MNE had lower attrition rates and a higher rate of FR than wired alarm therapy.

Meningitis due to Enterobacter aerogenes in the community associated with congenital dermal sinus in a Japanese infant.

Congenital dermal sinus is associated with meningitis caused by atypical pathogens. Although nosocomial infections with Enterobacter aerogenes in limited settings have been reported, community-acquired infections associated with congenital dermal sinus are rarely observed. We present the first non-neonatal case of a 3-month-old boy with meningitis due to Enterobacter aerogenes associated with congenital dermal sinus. The patient visited our hospital with fever and a skin dimple with lumbosacral hemangioma. He was diagnosed with meningitis based on cerebrospinal fluid (CSF) examination, which showed a cell count of 5717/µL. Subsequently, antimicrobial therapy with meropenem, cefotaxime (CTX), and vancomycin was initiated. His fever subsided, and the number of CSF cells decreased. Magnetic resonance imaging was performed for the dimple of the lumbosacral region, revealing the congenital dermal sinus. Enterobacter aerogenes was isolated from CSF and stool cultures, and treatment was adjusted to CTX alone based on susceptibility testing. However, the CSF culture remained positive. Although CTX was effective, the response to treatment was partial, and a switch to meropenem was required to achieve negative CSF cultures. In conclusion, Enterobacter aerogenes, although atypical, can cause community-acquired meningitis associated with congenital dermal sinus. Consistent with previous reports, in this case, a hemangioma on the back led to the diagnosis of congenital dermal sinus. Hence, systemic examination, including the back, is important. In addition, use of a third-generation cephalosporin (e.g., CTX) may not negate the CSF culture, even if it is effective. Thus, a switch to another drug (e.g., carbapenem) may be required.

Fecal impaction detected by imaging predicts recurrent urinary tract infection.

BACKGROUND: Few studies have evaluated the efficacy of ultrasonography (US) and abdominal radiography in assessing bladder and bowel dysfunction in children aged <24 months. We aimed to investigate the association between the risk of urinary tract infection (UTI) recurrence and fecal impaction using imaging findings. METHODS: The medical records of 121 children (aged <24 months) with initial febrile UTI (fUTI) who were admitted to the authors' institution from January 2004 to September 2019 were reviewed retrospectively. We evaluated the rectal diameters of children with suspected fecal impaction that were measured using transabdominal US, or the rectal diameters divided by the distance between the ischial spines that were measured using abdominal radiography. Based on previous reports, we defined fecal impaction as a transabdominal US score of >30 mm or an abdominal radiography score of >0.5. The definition of functional constipation was based on the child/adolescent Rome IV criteria - i.e., a maximum stool frequency of twice per week. RESULTS: The median age at initial fUTI diagnosis was 4 months. The occurrence of fecal impaction identified via imaging was significantly greater in patients with UTI recurrence than in those without recurrence: yes/no: 17/9 (65.4%) versus 35/60 (36.8%); P = 0.013. On the other hand, the occurrence rates of constipation based on stool frequency did not differ between the two groups. In multiple logistic analyses, fecal impaction detected via imaging was identified as an independent risk factor for fUTI recurrence. CONCLUSIONS: Fecal impaction observed via US and abdominal radiography may be useful in predicting the recurrence of fUTI in children.

Clinical, pathological, and genetic characteristics of cases with asymptomatic proteinuria not manifesting nephrotic syndrome at onset: a single-center retrospective study.

BACKGROUND: Cases with asymptomatic proteinuria (ASP) not manifesting nephrotic syndrome often pathologically show focal segmental glomerulosclerosis (FSGS). However, characteristics of those cases had not been intensively studied so far. METHODS: We retrospectively reviewed clinical, pathological, and genetic characteristics of 37 children (median age, 9.3 years) who underwent renal biopsy for persistent isolated proteinuria (urine protein-to-creatinine ratio: UP/C, > 0.2 g/g) between 2003 and 2019. Targeted next-generation sequencing (NGS) was utilized for all patients with FSGS, excluding those with secondary FSGS. RESULTS: At biopsy, all patients with FSGS (N = 14) had UP/C ≥ 0.5 g/g and the median UP/C was significantly higher in those with FSGS than those with minor glomerular abnormalities (MGA) (N = 23) (1.49 vs. 0.53 g/g, P < 0.001). Causative variants were found in seven patients with FSGS (TRPC6, WT1, ACTN4, and INF2 in 3, 2, 1, and 1 patient, respectively): all gene variants were in genes manifesting autosomal dominant inheritance mode. The proportion of the perihilar variant was significantly higher in the genetic FSGS patients than in the non-genetic FSGS patients (4/7 vs. 0/7, P < 0.05). Kaplan-Meier analysis showed that the renal survival rate after ASP diagnosis was significantly lower in the genetic FSGS patients than in the non-genetic FSGS and the MGA patients (P < 0.001). CONCLUSIONS: UP/C was a simple and useful predictive parameter for the diagnosis of FSGS. APS without nephrotic syndrome at onset may be associated with autosomal dominant causes of FSGS, especially in those with the perihilar variant.

Distribution of serum adiponectin isoforms in pediatric patients with steroid-sensitive nephrotic syndrome.

BACKGROUND: Serum adiponectin circulates in three multimeric isoforms: high-molecular-weight (HMW), middle-molecular-weight (MMW), and low-molecular-weight (LMW) isoforms. Potential change in the circulating adiponectin levels in patients with nephrotic syndrome (NS) remain unknown. This study aimed to assess the levels of total adiponectin and the distribution of its isoforms in pediatric patients with NS. METHODS: We sequentially measured total adiponectin and each adiponectin isoform levels at the onset of NS, initial remission, and during the remission period of the disease in 31 NS patients. We also calculated the ratios of HMW (%HMW), MMW (%MMW), and LMW (%LMW) to total adiponectin incuding 51 control subjects. RESULTS: The median of total serum adiponectin levels in patients were 36.7, 36.7, and 20.2 µg/mL at the onset, at initial remission, and during the remission period of NS, respectively. These values were significantly higher than those in control subjects. The median values of %HMW, %MMW, and %LMW values were 56.9/27.0/14.1 at the onset, 62.0/21.8/13.4 at the initial remission, and 58.1/21.7/17.5 at during the remission period of NS, respectively. Compared with control subjects, %HMW at initial remission and %MMW at the onset were high, and the %LMW values at the onset and at initial remission were low. CONCLUSIONS: In patients with NS, total serum adiponectin levels increase at the onset of the disease, and the ratio of adiponectin isoforms changes during the course of the disease. Further studies are needed to delineate the mechanisms between proteinuria and adiponectin isoforms change.

Reference serum creatinine levels according to sex, age, and height in children with Down syndrome.

Standard serum creatinine (S-Cr) levels in healthy children fluctuate with age and sex. However, it is unclear if this fluctuation in S-Cr levels is present for children with Down syndrome (DS) who show atypical growth rate. Therefore, we aimed to establish specific reference S-Cr levels for DS and compare them with the prevailing standard levels. We retrospectively reviewed 984 children with DS aged 3 months to 18 years who visited our medical center. Patients with diseases affecting S-Cr levels were excluded. We calculated the reference S-Cr levels according to sex, age, and length/height using medical records. A total of 3765 examinations of 568 children with DS were registered for this study. Ages and S-Cr levels were examined for boys (y = 0.032x + 0.20; r = 0.868, P < 0.0001), and girls (y = 0.024x + 0.23; r = 0.835, P < 0.0001). S-Cr levels in children aged >9 years were significantly higher in boys than in girls. The 430 children with DS aged 2-8 years were examined 1867 times. Height and S-Cr levels showed a significantly strong positive correlation (r = 0.670, P < 0.001) with regression equation y = 0.37x. The quintic equations calculated with S-Cr levels and length/height for boys (336 children, 2043 tests, r = 0.887) and girls (232 children, 1722 tests, r = 0.805) werey = - 6.132x5 + 32.78x4 - 67.86x3 + 68.31x2 - 33.14x + 6.41, and y = 0.09542x5 + 1.295x4 - 6.401x3 + 10.35x2 - 6.746x + 1.772. All calculated results varied from the standard levels for healthy children.Conclusion: This study established reference S-Cr levels and quintic equations specific for children with DS. These reference levels would be potentially useful in evaluating S-Cr levels and renal function in this population. What is Known: •Standard serum creatinine levels vary with age and sex to reflect muscle mass. •Reference serum creatinine levels specific to children with Down syndrome who show growth rates different from those of healthy children have not been established. What is New: •Serum creatinine levels in children with Down syndrome showed different trajectories for sex, age, and length/height when compared with the standard levels for healthy children. •This report on specific reference serum creatinine levels for children with Down syndrome is useful in the assessment of renal function in these children.

Is the estimated glomerular filtration rate formula useful for evaluating the renal function of Down syndrome?

BACKGROUND: Children with Down syndrome (DS) have different growth rates compared with normal children. The present study examined the reliability of a general formula, Uemura's formula, utilized in normal Japanese children to estimate renal function (estimated glomerular filtration rate - eGFR) in children with DS. METHODS: This study included 758 children aged 2-18 years with DS who visited our medical center. Patients with congenital heart disease, or congenital anomalies of the kidney or urinary tract detected via abdominal ultrasonography, chronic glomerulonephritis, and vesicoureteral reflux, etc., were excluded. Height and serum creatinine data gathered from 2421 examinations of 379 children with DS (224 boys and 155 girls) were used to evaluate Uemura's formula. RESULTS: The mean eGFR was lower in children with DS than in children without DS. Stage II chronic kidney disease was indicated in 44.6% of examinations and stage III in 0.8%. The association of eGFR with age differed between sexes. Boys with DS showed a significant but weak negative correlation between eGFR and age (r = -0.273, P < 0.001), whereas girls with DS showed a significant but very weak negative correlation (r = -0.111, P < 0.001). CONCLUSIONS: A new eGFR formula that takes into account specific growth rates and puberty is needed for children with DS because general renal function evaluation formulas are inappropriate for these patients.

Baseline characteristics and long-term outcomes of steroid-resistant nephrotic syndrome in children: impact of initial kidney histology.

BACKGROUND: Although many pediatric nephrologists consider focal segmental glomerulosclerosis (FSGS) and minimal change disease (MCD) as separate clinical entities, whether the initial histology could affect clinical courses in children with steroid-resistant nephrotic syndrome (SRNS) suspected of having an immune-based etiology remains unknown, especially for long-term outcomes. METHODS: We retrospectively reviewed long-term outcomes (> 3 years; median follow-up, 9.1 years) of 21 children with initial SRNS (FSGS, N = 9; MCD, N = 12) who achieved complete remission with immunosuppressive agents, including cyclosporine. RESULTS: At NS onset, incidence of acute kidney injury (67% vs. 8%, P < 0.05) and proportion of patients with non-selective proteinuria (56% vs. 0%, P < 0.01) were significantly higher in the FSGS group than the MCD group. Furthermore, median days until complete remission after treatment was significantly longer in the FSGS group than the MCD group (116 days vs. 45 days, P < 0.001). Although subsequent biopsy histology of the 12 patients in the MCD group was still identical in all MCD, three of nine patients in the FSGS group were reclassified from FSGS to MCD at second biopsy. At last visit, all patients maintained complete remission, and none developed chronic kidney disease. CONCLUSIONS: Initial presentation in the FSGS group was characterized by more severe clinical manifestations than the MCD group. If complete remission is achieved, FSGS and MCD in children with immune-mediated SRNS may constitute a single disease spectrum because the long-term outcomes are favorable, irrespective of initial histology.