The value of home-uroflowmetry in evaluation of voiding function in children with overactive bladder.

INTRODUCTION: Overactive bladder (OAB) in children is clinically common and seriously affects the physical and mental health of children. The voiding frequency (VF) is an important basis for the diagnosis of OAB. The emergence of home-uroflowmetry (HUF) has allowed the patients to record the VF while recording the uroflowmetry at home, and the voiding at home can show the real voiding situation. However, the use of HUF to assess OAB in children and its clinical significance has not been reported in the literature. Thus, this study investigate the value of HUF in evaluation of voiding function in children with OAB and survey the VF of healthy children in Mainland China. MATERIALS AND METHODS: From May 2021 to July 2023, 52 children with OAB aged 7-10 years, 48 age-matched volunteers (control group) accepted HUF. Daytime VF and nighttime VF, voided volume (VV) per time, 24-h voided volume (24h-VV), maximum flow rate (Qmax), voiding time (VT), and uroflow pattern were recorded and compute corrected maximum urine flow rate (cQmax). VF in 600 health pupils (7-10 years) from five primary schools in Henan Province China were selected for questionnaire survey by cross-sectional survey and multi-stage sampling methods. RESULTS: 52 children with OAB and 48 healthy children completed the available 48-h HUF recordings. 24-hour, daytime, and nighttime VF, and cQmax were higher in the OAB group than in the control group (P < 0.05). However, average VV, Qmax, and VT were lower in the OAB group than in the control group (P < 0.05). There was no significant difference in 24h-VV between two groups (P > 0.05). A total of 502 questionnaires qualified for statistical analysis, and the 24h-VF was 6.3 ± 0.95 times, daytime VF was 5.6 ± 0.89 times, and nighttime VF was 0.7 ± 0.59 times. There was no significant difference in the comparison of 24-h, daytime, and nighttime VF between boys and girls and in the comparison of VF by age (P > 0.05). Compared with the results of the questionnaire, the difference of VF in HUF control group was not statistically significant (P > 0.05). CONCLUSIONS: The VF in children is similar to that of adults and the HUF is a useful tool with the ability to more realistically record changes in voiding function in children with OAB.

Exploring the Genetic Risk of Childhood Daytime Urinary Incontinence: A Genome-Wide Association Study.

PURPOSE: Childhood incontinence is stigmatized and underprioritized, and a basic understanding of its pathogenesis is missing. Our goal was to identify risk-conferring genetic variants in daytime urinary incontinence (DUI). MATERIALS AND METHODS: We conducted a genome-wide association study in the Danish iPSYCH2015 cohort. Cases (3024) were identified through DUI diagnosis codes and redeemed prescriptions for DUI medication in children aged 5 to 20. Controls (30,240), selected from the same sample, were matched to cases on sex and psychiatric diagnoses, if any, and down-sampled to a 1:10 case:control ratio. Replication was performed in the Icelandic deCODE cohort (5475 cases/287,773 controls). Single-nucleotide polymorphism heritability was calculated using the genome-based restricted maximum likelihood method. Cross-trait genetic correlation was estimated using linkage disequilibrium score regression. Polygenic risk scores generated with LDpred2-auto and BOLT-LMM were assessed for association. RESULTS: Variants on chromosome 6 (rs12210989, OR = 1.24 [95% CI: 1.17-1.32], P = 3.21 × 10-12) and 20 (rs4809801, OR = 1.18 [95% CI: 1.11-1.25], P = 3.66 × 10-8) reached genome-wide significance and implicated the PRDM13 and RIPOR3 genes. Chromosome 6 findings were replicated (P = .024, OR = 1.09 [95% CI: 1.01-1.16]). Liability scale heritability ranged from 10.20% (95% CI: 6.40%-14.00%) to 15.30% (95% CI: 9.66%-20.94%). DUI and nocturnal enuresis showed positive genetic correlation (rg = 1.28 ± 0.38, P = .0007). DUI was associated with attention-deficit/hyperactivity disorder (OR = 1.098 [95% CI: 1.046-1.152], P < .0001) and body mass index (OR = 1.129 [95% CI: 1.081-1.178], P < .0001) polygenic risk. CONCLUSIONS: Common genetic variants contribute to the risk of childhood DUI and genes important in neuronal development and detrusor smooth muscle activity were implicated. These findings may help guide identification of new treatment targets.

Development of a Novel Prediction Tool for Response to First-Line Treatments of Monosymptomatic Nocturnal Enuresis: A Randomized, Controlled, International, Multicenter Study (DRYCHILD).

PURPOSE: Nocturnal urine volume and bladder reservoir function are key pathogenic factors behind monosymptomatic nocturnal enuresis (MNE). We investigated the predictive value of these together with other demographic and clinical variables for response to first-line treatments in children with MNE. MATERIALS AND METHODS: A randomized, controlled, international, multicenter study was conducted in 324 treatment-naïve children (6-14 years old) with primary MNE. The children were randomized to treatment with or without prior consideration of voiding diaries. In the group where treatment choice was based on voiding diaries, children with nocturnal polyuria and normal maximum voided volume (MVV) received desmopressin (dDAVP) treatment, and children with reduced MVV and no nocturnal polyuria received an enuresis alarm. In the other group, treatment with dDAVP or alarm was randomly allocated. RESULTS: A total of 281 children (72% males) were qualified for statistical analysis. The change of responding to treatment was 21% higher in children where treatment was individualized compared to children where treatment was randomly selected (risk ratio = 1.21 [1.02-1.45], P = .032). In children with reduced MVV and no nocturnal polyuria (35% of all children), individualized treatment was associated with a 46% improvement in response compared to random treatment selection (risk ratio = 1.46 [1.14-1.87], P = .003). Furthermore, we developed a clinically relevant prediction model for response to dDAVP treatment (receiver operating characteristic curve 0.85). CONCLUSIONS: The present study demonstrates that treatment selection based on voiding diaries improves response to first-line treatment, particularly in specific subtypes. Information from voiding diaries together with clinical and demographic information provides the basis for predicting response. CLINICAL TRIAL REGISTRATION NO.: NCT03389412.

Prevalence and relevant factors of nocturia and its impact on sleep quality in Chinese university students.

The purpose of this study was to investigate the prevalence and relevant factors of nocturia and its impact on sleep quality in university students in Mainland China. A large-scale survey was conducted on 14,000 university students from 3 universities in Henan province, China by using an anonymous questionnaire. The questionnaire collected the information from the past six months. The relationships between the prevalence of nocturia and its relevant factors were evaluated. A total of 13,874 questionnaires were collected and 13,104 qualified for statistical analysis. A total of 659 students suffered from clinically relevant nocturia (CRN) (4.56% in male and 5.34% in female). Both univariate analysis and the logistic stepwise regression model showed that the prevalence of nocturia was significantly related to female, history of enuresis, ease of waking up, urgency, frequency and RUTI (P < 0.05). The sleep quality and the university entrance score of CRN group was significantly lower than that of control group (P < 0.05). Nocturia was common in Chinese university students and showed a negative impact on sleep and academic performance. Gender of female, history of enuresis, ease of waking up, urgency, frequency and RUTI were relevant factors for CRN.

Bladder dysfunction in adolescents with type 1 diabetes.

BACKGROUND: It is increasingly significant that adults with diabetes experience lower urinary tract symptoms, however, there has been limited research in younger individuals with type 1 diabetes. OBJECTIVE: To investigate bladder function using non-invasive urodynamics as a potential indicator of autonomic neuropathy in adolescents with type 1 diabetes. This involved examining the association between urinary flow disturbances, reported symptoms, and results from other autonomic tests. STUDY DESIGN: Cross-sectional study enrolling 49 adolescents with type 1 diabetes and 18 control subjects. All participants underwent uroflowmetry and ultrasound scanning, completed the Composite Autonomic Symptom Score (COMPASS)-31 questionnaire, and were instructed to record their morning urine volume and voiding frequencies and report them back. Cardiovascular reflex tests (CARTs) and the quantitative sudomotor axon reflex test (QSART) were performed. RESULTS: The main results are shown in the Summary figure. DISCUSSION: In this study, urological abnormalities were not significantly more frequent in adolescents with diabetes, however, urological issues were observed. This is supported by previous findings of Szabo et al. who found that adolescents with type 1 diabetes had reduced flow acceleration and time to maximum flow compared to control subjects. In our study, we observed cases with reduced acceleration and prolonged uroflow curves, possibly indicating detrusor underactivity. People with diabetes had a higher risk of nocturia than healthy controls, which our results supported. Some adolescents reported urination twice per night. Based on these findings, it is considered beneficial to ask about urological symptoms annually to determine if more examinations (frequency-volume charts and uroflowmetry) are necessary and/or if any opportunities for treatment optimization exist. However, uroflowmetry has limitations, as bladder filling and emptying is a complex process involving multiple pathways and neurological centers, making it difficult to standardize and evaluate. Another limitation of this study was that our control group was smaller and consisted of fewer males than females, which could affect the results due to differences in anatomy and physiology in the lower urinary tract system. CONCLUSION: In conclusion, adolescents with type 1 diabetes, as well as healthy adolescents, frequently experience urological symptoms. Although urological abnormalities were not significantly more frequent in adolescents with diabetes in this study, the focus on nocturia and risk for bladder dysfunction seems relevant, even in adolescents without any other tests indicating autonomic dysfunction.

Outcome of tonsillotomy in children with obstructive sleep-disordered breathing.

OBJECTIVE/BACKGROUND: Most children treated for obstructive sleep disordered breathing (oSDB) are not systematically assessed by polysomnography (PSG) nor by structuredsymptom quantification before surgical treatment. The main objective of this study wasto investigate the effect of adeno-tonsillotomy (ATO) on symptom burden and PSGparameters. METHODS: Children aged 2-10 years with oSDB were selected for ATO based uponclinical findings according to current standards of care in Denmark. Each childunderwent standardized assessment before and 3 months after surgery, including aPSG, tonsil size assessment, and the Pediatric Sleep Questionnaire -Sleep RelatedBreathing Disorder (PSQ) to quantify symptom burden. Obstructive sleep apnea (OSA)was defined as an obstructive apnea-hypopnea index (oAHI) ≥2/h. Successfultreatment was defined as post-surgery oAHI ≤5/h, and complete cure as oAHI ≤2/h. RESULTS: Fifty-two children were included. Mean age was 5.0 years (SD ± 1.76). Thirteen children were identified with baseline oAHI <2/h. Significant improvement inOSA severity was observed in children with moderate-to-severe OSA, in whom oAHI decreased from 15.7/h to 2.6/h (p < 0.001). Treatment success was obtained in 85% and cure was obtained in 42% of children. PSQ-score significantly improved from 0.52 (CI 0.47-0.56) to 0.26 (CI 0.21-0.32) (p < 0.001). Baseline OSA severity was notcorrelated to baseline symptom burden nor to symptom relief after ATO. There were noserious adverse events. CONCLUSIONS: Adeno-tonsillotomy significantly reduced symptom burden in otherwise healthy children with oSDB symptoms. Significant improvement in oAHI was observedonly in children with moderate-to-severe OSA. We recommend combining clinicalevaluation with PSQ and oAHI.

Discontinuing absorbent pants in children with bedwetting: a randomized controlled trial.

The objective of this study is to examine the effect of discontinuing wearing protective garments (absorbent pyjama pants - APP) in children with severe childhood nocturnal enuresis (NE). The study employs a multicenter, parallel, randomized controlled trial. Following a 4-week run-in period, participants were randomly allocated in a 2:1 group allocation to discontinue or continue using APP. The research was conducted across seven European pediatric incontinence centers. The study included treatment-naïve children aged 4-8 years with severe (7/7 wet nights per week) mono-symptomatic NE, who had used nighttime protection for at least 6 months prior to the study. The study consisted of a 4-week run-in period (± 7 days), where all children slept wearing APP (DryNites®). At week 4 (± 7 days), if meeting randomization criteria (7/7 wet nights during the last week of run-in), participants were randomized to continue to sleep in APP or to discontinue their use for a further 4 weeks, with the option of another 4 weeks in the extension period. The primary outcome was the difference between groups of wet nights during the last week of intervention. Quality of life (QoL) and sleep were secondary endpoints. In total, 105 children (43 girls and 62 boys, mean age 5.6 years [SD 1.13]) were randomized (no-pants group n = 70, pants group n = 35). Fifteen children (21%) in the no-pants group discontinued early due to stress related to the intervention. Children in the no-pants group experienced fewer wet nights compared to the pants group during the last week (difference 2.3 nights, 95% CI 1.54-3.08; p < 0.0001). In the no-pants group, 20% responded to the intervention, of whom 13% had a full response. Clinical improvement was detected within 2 weeks. Sleep and QoL were reported as negatively affected by APP discontinuation in the extension period but not in the core period.    Conclusion: A ~ 10% complete resolution rate was associated with discontinuing APP. While statistically significant, the clinical relevance is debatable, and the intervention should be tried only if the family is motivated. Response was detectable within 2 weeks. Discontinuing APP for 4-8 weeks was reported to negatively affect QoL and sleep quality. No severe side effects were seen.Trial registration: Clinicaltrials.gov Identifier: NCT04620356; date registered: September 23, 2020. Registered under the name: "Effect of Use of DryNites Absorbent Pyjama Pants on the Rate of Spontaneous Resolution of Paediatric Nocturnal Enuresis (NE)."

The role of renal circadian biorhythms in lifelong LUTS.

INTRODUCTION: This article delves into the intricate relationship between kidney function, diuresis, and lower urinary tract symptoms (LUTS) throughout the transitions of the human lifespan. It explores circadian regulation of urine production, maturation of renal function from birth to adulthood, and effects of aging on kidney function and LUTS. The complex connections between these factors are highlighted, offering insights into potential interventions and personalized management strategies. METHODS: An international panel of seven experts engaged in online discussions, focusing on kidney function, diuresis, and LUTS throughout life. This manuscript summarizes expert insights, literature reviews, and findings presented during a webinar and subsequent discussions. RESULTS: Renal function undergoes significant maturation from birth to adulthood, with changes in glomerular filtration rate, diuresis, and tubular function. A circadian rhythm in urine production is established during childhood. Adolescents and young adults can experience persistent enuresis due to lifestyle factors, comorbidities, and complex physiological changes. In older adults, age-related alterations in kidney function disrupt the circadian rhythm of diuresis, contributing to nocturnal polyuria and LUTS. CONCLUSION: The interplay between kidney function, diuresis, and LUTS is crucial in understanding lifelong urinary health. Bridging the gap between pediatric and adult care is essential to address enuresis in adolescents and young adults effectively. For older adults, recognizing the impact of aging on renal function and fluid balance is vital in managing nocturia. This holistic approach provides a foundation for developing innovative interventions and personalized treatments to enhance quality of life for individuals with LUTS across all stages of life.

GFR measurements and ultrasound findings in 154 children with a congenital solitary functioning kidney.

BACKGROUND: Multicystic dysplastic kidney (MCDK) and unilateral renal agenesis (URA) are the most common reasons for a congenital solitary functioning kidney (SFK). We aimed to assess the presence of abnormalities in the congenital SFK and evaluate kidney function using chrome EDTA (CrEDTA) measurements. METHODS: We retrospectively reviewed the medical records of 154 children with MCDK and URA in the period from 2005 to 2022 to analyze results from ultrasound scans and CrEDTA glomerular filtration rate (GFR) examinations. RESULTS: Of 154 children with a solitary kidney due to MCDK (62%) or URA (38%), abnormalities on the congenital SFK were found in 13 children (8%). The abnormalities spontaneously resolved in 6 children (46%). The most common abnormality was hydronephrosis. Compensatory hypertrophy was found in 17% of the children within the first 6 months of life. 116 children (90%) had a standard GFR (sdGFR) above 75% of expected for the age. Out of those with a sdGFR below 75% of expected, 3 (23%) had abnormalities in the congenital SFK. There was no difference in sdGFR between children with MCDK and URA. CONCLUSIONS: Our study is the first using CrEDTA for GFR measurements and suggests that most children with a congenital SFK due to MCDK or URA have a kidney function within expected for the age. Compensatory hypertrophy of the SFK is found in a minority of children within the first six months of life, suggesting that this process is developing over time. The prevalence of abnormalities in the SFK seems low, however those with abnormalities (e.g. hydronephrosis) are at higher risk of reduced sdGFR.

The effect of methylphenidate for giggle incontinence in children.

INTRODUCTION: Giggle incontinence (GI) is a rare form of urinary incontinence that occurs during or immediately after laughing due to involuntary and complete bladder emptying. Few studies in the literature report that methylphenidate can be effective in treatment of this condition. OBJECTIVE: The aim of this study is to characterize children with GI and evaluate their response to methylphenidate, as well as describe treatment duration, dosage of methylphenidate, relapse rates after discontinuation of medication, and side effects. METHODS: Medical records and 48-h frequency-volume charts from children treated with methylphenidate for GI in the period January 2011-July 2021 were retrospectively analyzed. RESULTS: Eighteen children were diagnosed with GI and fulfilled inclusion criteria. Fifteen patients were included in analysis, as 3 out of 18 children decided not to take the methylphenidate that was prescribed. In total, 14 out of the 15 GI patients treated with methylphenidate experienced clinical effect. All patients included in the study had methylphenidate prescribed in a dose range of 5-20 mg daily. Treatment duration ranged from 30 to 1001 days, with a median of 152 days (IQR 114, 243.5). Ten children experienced complete response and two of those reported symptom relapse after discontinuation of the methylphenidate. Only mild and short-lasting side effects were reported by two patients. DISCUSSION: Our study demonstrates that methylphenidate is an effective treatment in children diagnosed with GI. Side effects are mild and uncommon.

Neuropathy in adolescents with type 1 diabetes: Confirmatory diagnostic tests, bedside tests, and risk factors.

AIMS: To estimate the prevalence of large fiber (LFN), small fiber (SFN), and autonomic neuropathy in adolescents with type 1 diabetes using confirmatory tests known from adults and to identify risk factors and bedside methods for neuropathy. METHODS: Sixty adolescents with type 1 diabetes (diabetes duration > five years) and 23 control subjects underwent neurological examination and confirmatory diagnostic tests for neuropathy, including nerve conduction studies, skin biopsies determining intraepidermal nerve fiber density, quantitative sudomotor axon reflex test (QSART), cardiovascular reflex tests (CARTs), and tilt table test. Possible risk factors were analyzed. Bedside tests (biothesiometry, DPNCheck®, Sudoscan, and Vagus®device) were compared with the confirmatory tests using ROC analysis. RESULTS: The prevalence of neuropathies in the adolescents with diabetes (mean HbA1c 7.6% (60 mmol/mol)) was as follows: 14% confirmed/26% subclinical LFN, 2% confirmed/25% subclinical SFN, 20% abnormal QSART, 8% abnormal CARTs, and 14% orthostatic hypotension. Higher age, higher insulin dose, previous smoking, and higher triglycerides level were found to increase the relative risk for neuropathy. The bedside tests showed poor to acceptable concordance with the confirmatory tests (all, AUC ≤ 0.75). CONCLUSIONS: The diagnostic tests confirmed the presence of neuropathy in adolescents with diabetes and underscore the importance of prevention and screening.

Differences in the urinary metabolome and proteome between wet and dry nights in children with monosymptomatic nocturnal enuresis and nocturnal polyuria.

BACKGROUND: Nocturnal enuresis (NE) is a common disease with multiple pathogenic mechanisms. This study aimed to compare levels of metabolites and proteins between wet and dry nights in urine samples from children with monosymptomatic NE (MNE). METHODS: Ten boys with MNE and nocturnal polyuria (age: 7.6 ± 1.3 years) collected their total nighttime urine production during a wet and a dry night. Untargeted metabolomics and proteomics were performed on the urine samples by liquid chromatography coupled with high-mass accuracy tandem mass spectrometry (LC-MS/MS). RESULTS: On wet nights, we found reduced urine osmolality (P = 0.025) and increased excretion of urinary potassium and sodium by a factor of, respectively, 2.1 (P = 0.038) and 1.9 (P = 0.19) compared with dry nights. LC-MS identified 59 metabolites and 84 proteins with significantly different levels between wet and dry nights (fold change (FC) < 0.67 or > 1.5, P < 0.05). Some compounds were validated by different methodologies. During wet nights, levels of compounds related to oxidative stress and blood pressure, including adrenalin, were increased. We found reduced levels of aquaporin-2 on wet nights. The FCs in the 59 metabolites were positively correlated to the FCs in the same metabolites identified in urine samples obtained during the evening preceding wet and dry nights. CONCLUSIONS: Oxidative stress, which in the literature has been associated with nocturia and disturbances in sleep, might be increased during wet nights in children with MNE. We further found evidence of increased sympathetic activity. The mechanisms related to having wet nights in children with MNE seem complex, and both free water and solute handling appear to be important. A higher resolution version of the Graphical abstract is available as Supplementary information.

The genetics of incontinence: A scoping review.

The genetic causes underlying incontinence in both children and adults have begun to be unravelled during the last decades. The aim of this scoping review is to synthesize current knowledge on the genetics of childhood and adult urinary and faecal incontinence, identify similarities between different incontinence subgroups, and identify knowledge gaps to aid future research. PRISMA-ScR was used, and 76 studies were included. Early epidemiological family and twin studies suggest high heritability of incontinence. Linkage studies provide evidence for the existence of rare genetic variants; however, these variants have not been identified. Later candidate gene association studies and recent genome-wide association studies provide the first preliminary evidence that common risk variants also play a role. The genetics of incontinence in children and adults has predominantly been studied separately, but this review identifies for the first time the endothelin system as a potential common pathophysiological pathway. Overall, these findings strengthen the hypothesis that genetic variants play a prominent role in the pathogenesis of incontinence. Future research should include hypothesis-free studies of rare and common variants in large well-characterized cohorts with incontinence. Studies should include different age groups and ethnicities and both sexes to fully reveal the genetics of incontinence.

The efficacy of standard urotherapy in the treatment of nocturnal enuresis in children: A systematic review.

INTRODUCTION: Standard urotherapy in children with nocturnal enuresis (NE) is first-line treatment according to the current International Children's Continence Society (ICCS) guidelines. ICCS defines standard urotherapy as information and demystification, instruction in how to resolve lower urinary tract dysfunction, lifestyle advice, registration of symptoms and voiding habits, and support and encouragement. These interventions often are time consuming and some aspects of urotherapy, such as fluid restrictions, can be a frustrating process for a child, which emphasizes the importance of clarifying their relevance. The purpose of this review is to perform a systematic search in literature to evaluate the use of standard urotherapy in the treatment of children with primary NE (PNE). STUDY DESIGN: A systematic literature search was conducted in MEDLINE, Embase, and CENTRAL based on the key concepts of standard urotherapy and NE. We identified 2,476 studies. After a systematic selection process using the Covidence tool, 39 studies were included. The quality of the studies was assessed by the QualSyst Checklist. Our protocol adheres to the PRISMA statement and was registered in PROSPERO database (CRD42020185611). RESULTS: Most of the 39 included studies scored low in quality. All studies combined several urotherapy interventions and studied different study populations. Twenty-two randomized controlled trials (RCTs) were included, which reported 0-92% of children being dry after urotherapy treatment. Three RCTs, all individualizing and optimizing drinking and voiding during the day and practicing optimal toilet posture, scored higher in quality based on the QualSyst score, and reported few children experiencing complete resolution of NE (5-33%). Eight studies compared the efficacy of urotherapy to a control group, however, conflicting results were found. DISCUSSION: This systematic review presents available literature in the field of standard urotherapy in the treatment of children with PNE. One possible explanation for low efficacy rates of urotherapy in NE is the large heterogeneity of the study populations and interventions. Additionally, the intervention period and the intensity of intervention can have an impact on the outcome. CONCLUSION: The number of clinical studies on standard urotherapy in children with NE is limited and many of them are of poor quality. High quality research in a well-defined NE population is needed to establish the role of standard urotherapy in first-line treatment of children with NE or as an add-on to other first line treatments. We conclude that at present there is insufficient evidence for recommending standard urotherapy to children with PNE as a first line treatment modality.

Two nights of home polysomnography in healthy 7-14-year-old children - Feasibility and intraindividual variability.

OBJECTIVE: Attended polysomnography (PSG) is the gold standard for childhood sleep evaluation. There is, however, only limited information regarding repeated ambulatory PSG in children. We aimed to test whether in hospital attached level 2 home PSG is feasible and reproducible in healthy children. METHODS: We recruited healthy children aged 7-14 years to undergo two nights of full level 2 PSG. The PSG equipment was attached at the hospital on the day of the sleep test and all recordings were performed at home. Subjective sleep quality, nocturnal urine production, sleep time and number of awakenings were documented for a week in connection to the first PSG night. RESULTS: Thirty-three children were recruited of whom 32 children (aged 11 ± 2.1 years) underwent two nights of PSG. All 64 PSGs were technically adequate for sleep evaluation. We found mean sleep efficiency of 94% and mean total sleep time of 8.4 h. Sleep stages distribution with 5.9% N1, 46.8% N2, 24.3% N3 and 22.8% REM sleep. We found poorer subjective sleep quality, more self-reported awakenings, and shorter total sleep time on nights with PSG compared to nights without PSG with no differences between PSG study nights. No differences in nocturnal urine production were found between nights with and without PSG. The comparison of PSG variables between the two PSG nights revealed no first night effect. CONCLUSIONS: Type 2 PSG recording is feasible for sleep evaluation in children 7-14 years of age producing good data quality. We found no first night effect on PSG variables. www. CLINICALTRIALS: gov Registration number: NCT03477812.

Functional constipation as a risk factor for pyelonephritis and recurrent urinary tract infection in children.

AIM: Acute pyelonephritis is one of the most common bacterial infections in childhood. This potentially serious condition can lead to renal scarring, loss of kidney function and hypertension. The aim of this study was to identify risk factors associated with pyelonephritis in children without kidney or urinary tract abnormalities. METHODS: Medical records of children aged 4-18 diagnosed with 1st time pyelonephritis from 2016 to 2021 were retrospectively analysed. Children with abnormal kidney ultrasound were excluded. In addition to demographic data, information on bladder and bowel function was extracted together with habits of fluid intake. RESULTS: A total of 105 patients were diagnosed with 1st time pyelonephritis. Of these, 47% were diagnosed with constipation according to the Rome IV criteria within a mean follow-up period of 167 days after their pyelonephritis, which is markedly higher than the estimated prevalence of constipation in the background population. Constipation was positively associated with recurrent urinary tract infection (p = 0.01). CONCLUSION: Constipation is associated with pyelonephritis and recurrent urinary tract infection in children (primarily girls) 4-18 years of age without evident kidney or urinary tract abnormalities. We recommend systematic evaluation of bowel and bladder function after 1st time pyelonephritis in all children >4 years.

Narrative update of clinical trials with antihypertensive drugs in children and adolescents.

Introduction: To date, our knowledge on antihypertensive pharmacological treatment in children and adolescents is still limited because there are few randomized clinical trials (CTs), hampering appropriate management. The objective was to perform a narrative review of the most relevant aspects of clinical trials carried out in primary and secondary hypertension. Methods: Studies published in PubMed with the following descriptors: clinical trial, antihypertensive drug, children, adolescents were selected. A previous Cochrane review of 21 randomized CTs pointed out the difficulty that statistical analysis could not assess heterogeneity because there were not enough data. A more recent meta-analysis, that applied more stringent inclusion criteria and selected 13 CTs, also concluded that heterogeneity, small sample size, and short follow-up time, as well as the absence of studies comparing drugs of different classes, limit the utility. Results: In the presented narrative review, including 30 studies, there is a paucity of CTs focusing only on children with primary or secondary, mainly renoparenchymal, hypertension. In trials on angiotensin converting enzyme inhibitors (ACEI), angiotensin receptor blockers (ARBs), calcium channel blockers (CCBs) and diuretics, a significant reduction of both SBP and DBP in mixed cohorts of children with primary and secondary hypertension was achieved. However, few studies assessed the effect of antihypertensive drugs on hypertensive organ damage. Conclusions: Given the increasing prevalence and undertreatment of hypertension in this age group, innovative solutions including new design, such as 'n-of-1', and optimizing the use of digital health technologies could provide more precise and faster information about the efficacy of each antihypertensive drug class and the potential benefits according to patient characteristics.

Parathyroid hormone and phosphate homeostasis in patients with Bartter and Gitelman syndrome: an international cross-sectional study.

BACKGROUND: Small cohort studies have reported high parathyroid hormone (PTH) levels in patients with Bartter syndrome and lower serum phosphate levels have anecdotally been reported in patients with Gitelman syndrome. In this cross-sectional study, we assessed PTH and phosphate homeostasis in a large cohort of patients with salt-losing tubulopathies. METHODS: Clinical and laboratory data of 589 patients with Bartter and Gitelman syndrome were provided by members of the European Rare Kidney Diseases Reference Network (ERKNet) and the European Society for Paediatric Nephrology (ESPN). RESULTS: A total of 285 patients with Bartter syndrome and 304 patients with Gitelman syndrome were included for analysis. Patients with Bartter syndrome type I and II had the highest median PTH level (7.5 pmol/L) and 56% had hyperparathyroidism (PTH >7.0 pmol/L). Serum calcium was slightly lower in Bartter syndrome type I and II patients with hyperparathyroidism (2.42 versus 2.49 mmol/L; P = .038) compared to those with normal PTH levels and correlated inversely with PTH (rs -0.253; P = .009). Serum phosphate and urinary phosphate excretion did not correlate with PTH. Overall, 22% of patients had low serum phosphate levels (phosphate-standard deviation score < -2), with the highest prevalence in patients with Bartter syndrome type III (32%). Serum phosphate correlated with tubular maximum reabsorption of phosphate/glomerular filtration rate (TmP/GFR) (rs 0.699; P < .001), suggesting renal phosphate wasting. CONCLUSIONS: Hyperparathyroidism is frequent in patients with Bartter syndrome type I and II. Low serum phosphate is observed in a significant number of patients with Bartter and Gitelman syndrome and appears associated with renal phosphate wasting.