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) 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 (RR = 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 (RR = 1.46 (1.14-1.87), P = .003). Furthermore, we developed a clinically relevant prediction model for response to dDAVP treatment (ROC 0.85). CONCLUSIONS: The present study demonstrates that treatment selection based on voiding diaries improve 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.

Potential clinical applications of current and future oral forms of desmopressin (Review).

Desmopressin is a synthetic analogue of vasopressin and a selective vasopressin receptor 2 agonist. It was first synthesised in 1967 and utilised for its antidiuretic properties. It is also used in bleeding disorders to enhance clotting. Other potential uses of the drug have been reported. The present review aims to provide a broad overview of the literature on potential further uses of oral forms of desmopressin. Key therapeutic areas of interest were identified based on known physiological activities/targets of desmopressin or reports of an effect of desmopressin in the literature. The feasibility of adequate dosing with oral forms of the drug was also considered. Systematic literature searches were carried out using the silvi.ai software for the identified areas, and summaries of available papers were included in tables and discussed. The results of the searches showed that desmopressin has been investigated for its efficacy in a number of areas, including bleeding control, renal colic, the central nervous system and oncology. Evidence suggests that oral desmopressin may have the potential to be of clinical benefit for renal colic and bleeding control in particular. However, further research is needed to clarify its effect in these areas, including randomised controlled studies and studies specifically of oral formulations (and doses). Further research may also yield findings for cancer, cognition and overactive bladder.

Transition in enuresis patients: Identifying the gaps and opportunities for the future.

BACKGROUND: Nocturnal enuresis is generally considered a children's condition, yet it may persist 1%-2% in adolescence and early adulthood. Refractory patients often demand follow-up by multidisciplinary teams, which is only restricted to some of the expert tertiary centers. However, there are no standardized transition programs/guidelines when follow-up must be passed from pediatric to adult healthcare providers. AIM, MATERIALS & METHODS: To investigate this issue, we conducted a literature search on enuresis transition, which resulted in no articles. We, therefore, proceeded in a rescue search strategy: we explored papers on transition programs of conditions that may be related and/or complicated by enuresis, nocturia, or other urinary symptoms (chronic diseases, CKD, bladder dysfunction, kidney transplant, neurogenic bladder). RESULTS: These programs emphasize the need for a multidisciplinary approach, a transition coordinator, and the importance of patient and parent participation, practices that could be adopted in enuresis. The lack of continuity in enuresis follow-up was highlighted when we investigated who was conducting research and publishing on enuresis and nocturia. Pediatric disciplines (50%) are mostly involved in children's studies, and urologists in the adult ones (37%). DISCUSSION: We propose a stepwise approach for the transition of children with enuresis from pediatric to adult care, depending on the clinical subtype: from refractory patients who demand more complex, multidisciplinary care and would benefit from a transition coordinator up to children/young adults cured of enuresis but who persist in having or present lower urinary tract symptoms (LUTS)/nocturia later on. In any case, the transition process should be initiated early at the age of 12-14 years, with adequate information to the patient and parents regarding relapses or LUTS/nocturia occurrence and of the future treating general practitioner on the enuresis characteristics and comorbidities of the patient.

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.

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.

Circadian rhythm of water and solute excretion in nocturnal enuresis.

BACKGROUND: Nocturnal polyuria (NP) due to a suppressed vasopressin circadian rhythm is a well-documented pathogenetic mechanism in enuresis, mainly studied in monosymptomatic enuresis. A substantial percentage of patients do not respond to desmopressin. This suggests that NP may not only be related to vasopressin, but that other kidney components play a role. Solute handling and osmotic excretion have been investigated in the past, especially in refractory patients. Nevertheless, data in treatment-naïve populations with information on timing overnight are sparse. This study aims to investigate the diuresis and solute excretion in treatment-naïve patients with or without NP, with emphasis on circadian rhythms. METHODS: Retrospective analysis of 403 treatment-naïve children 5-18 years with severe enuresis (> 8 nights/2 weeks). Circadian rhythms were evaluated by a 24-h urine collection in 8 timed portions (4 day, 4 nighttime) at in-home settings. Urine volume, osmolality, and creatinine were measured. Patients were subdivided into three groups according to nocturnal diuresis (ND) and Expected Bladder Capacity (EBCage) ratio: (a) < 100%, (b) 100-129%, (c) > 130%. RESULTS: All groups maintained circadian rhythm for diuresis and diuresis rates. Patients with higher ND (100-129% and > 130% EBCage) had higher daytime volumes and less pronounced circadian rhythm. In the ND group > 130% EBCage, the ND rate was higher during the first night collection and osmotic excretion was significantly higher overnight. CONCLUSIONS: Overall 24-h fluid intake (reflected by 24-h diuresis) and nutritional intake (24-h osmotic excretion) might play a role in enuresis. Increased diuresis rate early in the night can be important in some patients, whereas the total night volume can be important in others. A higher resolution version of the Graphical abstract is available as Supplementary Information.

The Influence of Salt Sensitivity Phenotype on Sodium Excretion and Diuresis: A Chrononutrition Pilot Study.

Background: Chrononutrition studies on interaction of diet/nutrients on endogenous circadian clocks and meal timing on metabolic homeostasis may be of importance in the management of nocturnal polyuria (NP), owing to loss of circadian rhythm in nighttime urination. Dietary salt restriction is an increasingly popular lifestyle recommendation for NP patients. Aim: This study aims to evaluate the effect of an acute salt load on diuresis and to study the phenomenon of salt sensitivity. Methodology. Young, healthy men (n = 21, fasted and sober) ingested 500 ml of water on the control day and 8 g and 12 g of salt with water (500 ml) on two other days. Blood and urine samples were collected at 0 hrs, 2 hrs, and 4 hrs and voided volumes were recorded. Diuresis, serum and urine osmolality, sodium, potassium, urea, and creatinine were measured. Salt sensitivity was determined based on the rate of sodium excretion. Results: Compared to 8 g, ingestion of 12 g of salt significantly increased diuresis after 4 hrs. Pure water load induced fast diuresis, whereas salt and water load initially reduced diuresis and promoted late increase in diuresis. The total voided volume was significantly lower in the salt sensitive individuals. Conclusion: Taken together, salt sensitivity profile and type and time of fluid intake are important considerations to build effective personalized lifestyle recommendations for NP patients, which needs further investigation.

Impact of New vs. Old International Children's Continence Society Standardization on the Classification of Treatment Naïve Enuresis Children at Screening: The Value of Voiding Diaries and Questionnaires.

Expert consensus papers recommend differentiating enuresis using questionnaires and voiding diaries into non- (NMNE) and monosymptomatic enuresis (MNE) is crucial at intake to decide the most appropriate workout and treatment. This national, Belgian, prospective study investigates the correlation, consistency, and added value of the two methods, the new against the old International Children's Continence Society (ICCS) definitions, and documents the prevalence of the two enuresis subtypes in our population. Ninety treatment-naïve enuretic children were evaluated with the questionnaire, and the voiding diary and the two clinical management tools were compared. Almost 30% of the children had a different diagnosis with each method, and we observed inconsistencies between them in registering Lower Tract Symptoms (κ = -0.057-0.432 depending on the symptom). Both methods had a high correlation in identifying MNE (rs = 0.612, p = 0.001) but not for NMNE (rs = 0.127, p = 0.248). According to the latest ICCS definitions, the incidence of MNE was significantly lower (7 vs. 48%) with the old standardization. Conclusion: The voiding diary and the questionnaire, as recommended by the ICCS at the screening of treatment-naïve enuretic patients, are considerably inconsistent and have significantly different sensitivities in identifying LUTS and thus differentiating MNE from NMNE. However, the high incidence of LUTS and very low prevalence of MNE suggest that differentiating MNE from NMNE to the maximum might not always correlate with different therapy responses.

Desmopressin oral lyophilisate in young children: new insights in pharmacokinetics and pharmacodynamics.

OBJECTIVE: To study the pharmacokinetic (PK)/pharmacodynamic (PD) characteristics of desmopressin (dDAVP) oral lyophilisate in children below the age of 8 years with special emphasis on age-related and size-related differences in bioavailability. DESIGN: Open label, non-randomised, interventional PK and PD trial. SETTING: Single-centre study. PATIENTS: Children (age: 6 months to 8 years) with nocturnal polyuria, including both children with uropathy or nephropathy (glomerular filtration rate >60 mL/min/1.73 m²) and children (age: 5-8 years) with severe monosymptomatic nocturnal enuresis, who were unresponsive to treatment with 400 µg of the dDAVP tablet for at least 1 month. INTERVENTIONS: After a water load, dDAVP was administered sublingually as a single dose of oral lyophilisate. Subsequently, blood and urine samples were collected until 7 hours post-administration. MAIN OUTCOME MEASURES: Non-compartmental analysis of PK parameters was performed based on dDAVP concentrations in both plasma and urine. To evaluate the effect of dDAVP lyophilisate (PD parameters), the urinary concentration capacity (urine osmolality (mOsm/kg)) and antidiuretic effect (diuresis rate (mL/kg/h)) were calculated. RESULTS: The PK data support the need for size-dependent dosing in children. Body weight was shown to be a significant covariate for apparent clearance (CL/F) and apparent volume of distribution (Vd/F). A double absorption peak of dDAVP lyophilisate in the first 2 hours post-administration was demonstrated. CONCLUSIONS: For the first time, a double absorption profile of dDAVP lyophilisate was found in children, questioning extrapolation of bioequivalence from adults towards children. Moreover, the need for size-adapted dosing regimens of dDAVP lyophilisate in young children is indicated. TRIAL REGISTRATION NUMBER: NTC02584231.

Could Evening Dietary Protein Intake Play a Role in Nocturnal Polyuria?

Urea is the most abundant and the largest contributing factor for urine osmolality. Urinary urea excretion is highly interrelated with dietary protein intake. Accordingly, an increase of urinary urea excretion due to high protein diet may lead to urea-induced osmotic diuresis. This study aims to explore the association between nocturnal polyuria (NP) and urea. This is a post hoc analysis of a prospective observational study of subjects who completed a renal function profile between October 2011 and February 2015 (n = 170). Each subject underwent a 24 h urine collection, which included 8 urine samples collected at 3 h intervals. Urine volume, osmolality, creatinine, urea and sodium were determined. Urinary urea excretion was used to estimate dietary protein intake. Compared to the control group, subjects with NP exhibited significantly higher nighttime urea and sodium excretion. Estimated evening dietary protein intake was correspondingly significantly higher amongst the NP subgroup. Nighttime diuresis rate was positively associated with age and nighttime free water clearance, creatinine clearance, sodium excretion, and urea excretion in NP subjects. Therefore, increased nocturnal urinary urea excretion may reflect an additional important mediator of nocturia owing to excess nocturnal urine production.

Pediatric Pharmacology of Desmopressin in Children with Enuresis: A Comprehensive Review.

Desmopressin is a synthetic analogue of the natural antidiuretic hormone arginine vasopressin. Over the years, it has been clinically used to manage nocturnal polyuria in children with enuresis. Various pharmaceutical formulations of desmopressin have been commercialized for this indication-nasal spray, nasal drops, oral tablet and oral lyophilizate. Despite the fact that desmopressin is a frequently prescribed drug in children, its use and posology is based on limited pediatric data. This review provides an overview of the current pediatric pharmacological data related to the different desmopressin formulations, including their pharmacokinetics, pharmacodynamics and adverse events. Regarding the pharmacokinetics, a profound food effect on the oral bioavailability was demonstrated as well as different plasma concentration-time profiles (double absorption peak) of the desmopressin lyophilizate between adults and children. Literature about maturational differences in distribution, metabolism and excretion of desmopressin is rather limited. Regarding the pharmacodynamics, formulation/dose/food effect and predictors of response were evaluated. The lyophilizate is the preferred formulation, but the claimed bioequivalence in adults (200 µg tablet and 120 µg lyophilizate), could not be readily extrapolated to children. Prescribing the standard flat-dose regimen to the entire pediatric population might be insufficient to attain response to desmopressin treatment, whereby dosing schemes based on age and weight were proposed. Moreover, response to desmopressin is variable, whereby complete-, partial- and non-responders are reported. Different reasons were enumerated that might explain the difference in response rate to desmopressin observed: different pathophysiological mechanisms, bladder capacity and other predictive factors (i.e. breast feeding, familial history, compliance, sex, etc.). Also, the relapse rate of desmopressin treatment was high, rendering it necessary to use a pragmatic approach for the treatment of enuresis, whereby careful consideration of the position of desmopressin within this treatment is required. Regarding the safety of the different desmopressin formulations, the use of desmopressin was generally considered safe, but additional measures should be taken to prevent severe hyponatremia. To conclude the review, to date, major knowledge gaps in pediatric pharmacological aspects of the different desmopressin formulations still remain. Additional information should be collected about the clinical relevance of the double absorption peak, the food effect, the bioequivalence/therapeutic equivalence, the pediatric adapted dosing regimens, the study endpoints and the difference between performing studies at daytime or at nighttime. To fill in these gaps, additional well designed pharmacokinetic and pharmacodynamic studies in children should be performed.

An Integrated Paediatric Population PK/PD Analysis of dDAVP: How do PK Differences Translate to Clinical Outcomes?

INTRODUCTION: The bioequivalence of two formulations of desmopressin (dDAVP), a vasopressin analogue prescribed for nocturnal enuresis treatment in children, has been previously confirmed in adults but not in children. In this study, we aimed to study the pharmacokinetics (PK) and pharmacodynamics (PD) of these two formulations, in both fasted and fed children, including patients younger than 6 years of age. METHODS: Previously published data from one PK study and one PK/PD study in children aged between 6 and 16 years were combined with a new PK/PD study in children aged between 6 months and 8 years, and analysed using population PK/PD modelling. Simulations were performed to further explore the relative bioavailability of both formulations and evaluate current dosing strategies. RESULTS: The complex absorption behaviour of the lyophilizate was modelled using a double input, linked to a one-compartmental model with linear elimination and an indirect response model linking dDAVP concentration to produced urine volume and osmolality. The final model described the observed data well and elucidated the complexity of bioequivalence and therapeutic equivalence of the two formulations. Simulations showed that current dosing regimens using a fixed dose of lyophilizate 120 µg is not adequate for children, assuming children to be in the fed state when taking dDAVP. A new age- and weight-based dosing regimen was suggested and was shown to lead to improved, better tailored effects. CONCLUSIONS: Bioequivalence and therapeutic equivalence data of two formulations of the same drug in adults cannot be readily extrapolated to children. This study shows the importance of well-designed paediatric clinical trials and how they can be analysed using mixed-effects modelling to make clinically relevant inferences. A follow-up clinical trial testing the proposed dDAVP dosing regimen should be performed. CLINICAL TRIAL REGISTRATION: This trial has been registered at www.clinicaltrials.gov (identifier NCT02584231; EudraCT 2014-005200-13).

Ethical considerations of researchers conducting pediatric clinical drug trials: a qualitative survey in two Belgian university children's hospitals.

There is a general consensus about the underlying theoretical ethical principles that ground the practice of pediatric clinical trials: scientific necessity, good risk/benefit ratio, minimized burden, and parental consent/child assent. However, these principles are so broadly construed that it is not always clear how they should be applied in clinical practice. We conducted a qualitative study at Ghent University Hospital and the hospital of the Dutch-speaking university of Brussels on how researchers weigh ethical principles, assess the risk/benefit balance, estimate patient experience, and experience informed consent procedures in pediatric drug studies. Based on our assessment of the burden and risk versus benefit ratio in 62 pediatric drug research protocols, we selected 21 studies for further study to maximize diversity. Twenty-seven researchers (17 physicians, 10 study nurses) completed a qualitative survey about their study. We compared their responses to our assessments. The risk benefit assessment of our participants about their own research projects resembled our assessment almost perfectly. Assessing burden appeared to be more subjective. The researchers were confident in their ability to obtain valid consent. However, we question whether this confidence is warranted. CONCLUSION: We argue for constant ethical reflexivity in pediatric clinical trials, because broad ethical principles are not always easy to apply to specific situations. What is Known: • Several international guidelines and a large body of scientific literature indicate a broad consensus about the basic ethical framework for pediatric clinical trials, based on risk benefit assessment and respect for autonomy. • Little is known about how researchers implement these broad principles in practice. What is New: • Researchers' risk/benefit assessments about their own studies resembled the assessment of neutral peers, assessing burden was more subjective. • Researchers were very confident in their ability to obtain valid informed consent.

The choice between deceased- vs living-donor renal transplantation in children: Analysis of data from a Belgian tertiary center.

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

Paediatric departments need to improve residents' training in adolescent medicine and health: a position paper of the European Academy of Paediatrics.

In many European countries, paediatric junior staff has no formal training in adolescent medicine and is ill-equipped to deal with issues and health problems such as substance use, unprotected sex, eating disorders and transition to adult care. This position paper of the European Academy of Paediatrics proposes a set of competency-based training goals and objectives as well as pedagogic approaches that are expected to improve the capacity of paediatricians to meet the needs of this important segment of the paediatric population. The content has been developed from available publications and training programmes and mostly covers the generic aspects of adolescent healthcare, such as how to communicate effectively, how to review and address lifestyles, how to perform a respectful and relevant physical examination, how to address common problems of adolescents and how to support adolescents in coping with a chronic condition. CONCLUSION: The European Academy of Paediatrics urges national bodies, paediatric associations and paediatric teaching departments to adopt these training objectives and put them into practice, so that paediatricians will be better prepared in the future to meet the challenge of delivering appropriate and effective healthcare to adolescents.

Claiming desmopressin therapeutic equivalence in children requires pediatric data: a population PKPD analysis.

PURPOSE: For a new formulation of a drug, only pharmacokinetic bioequivalence with the original formulation has to be demonstrated in healthy, young adults. However, "children are not small adults," and to guarantee a safe and effective treatment, age-adapted drug development is required. Desmopressin, a vasopressin analogue prescribed for nocturnal enuresis in children, was studied as an example formulation first developed in adults and then extrapolated to a pediatric indication. METHODS: Population pharmacokinetic and pharmacodynamic modeling was used to analyze previously published desmopressin data of 18 children suffering from nocturnal enuresis. The main objective was the comparison of the therapeutic equivalence of two desmopressin formulations: tablet and lyophilisate. The measurements for pharmacokinetics and pharmacodynamics were respectively plasma desmopressin concentration and urine osmolality and diuresis. RESULTS: The half maximal inhibitory concentration for inhibition of urine production was 0.7 pg/mL lower for the lyophilisate than for the tablet. The effect of formulation on the half maximal inhibitory concentration seems to suggest that the 120-µg lyophilisate has a more pronounced effect on the urine volume and osmolality than the 200-µg tablet, even when the same exposure is achieved. CONCLUSIONS: A new indirect response model for desmopressin was constructed and validated, using a previously built pharmacokinetic model and additional pharmacodynamic data. In order to draw solid conclusions regarding the efficacy and safety of desmopressin in children, pharmacokinetics and pharmacodynamics data should be analyzed together. This study adds proof to potential differences in pediatric and adult pharmacokinetic and pharmacodynamic properties of desmopressin and exemplifies the need for pediatric clinical trials, not only for every new drug but also for every new formulation.

Effects of Food and Pharmaceutical Formulation on Desmopressin Pharmacokinetics in Children.

INTRODUCTION: Desmopressin is used for treatment of nocturnal enuresis in children. In this study, we investigated the pharmacokinetics of two formulations-a tablet and a lyophilisate-in both fasted and fed children. METHODS: Previously published data from two studies (one in 22 children aged 6-16 years, and the other in 25 children aged 6-13 years) were analyzed using population pharmacokinetic modeling. A one-compartment model with first-order absorption was fitted to the data. Covariates were selected using a forward selection procedure. The final model was evaluated, and sensitivity analysis was performed to improve future sampling designs. Simulations were subsequently performed to further explore the relative bioavailability of both formulations and the food effect. RESULTS: The final model described the plasma desmopressin concentrations adequately. The formulation and the fed state were included as covariates on the relative bioavailability. The lyophilisate was, on average, 32.1 % more available than the tablet, and fasted children exhibited an average increase in the relative bioavailability of 101 % in comparison with fed children. Body weight was included as a covariate on distribution volume, using a power function with an exponent of 0.402. Simulations suggested that both the formulation and the food effect were clinically relevant. CONCLUSION: Bioequivalence data on two formulations of the same drug in adults cannot be readily extrapolated to children. This was the first study in children suggesting that the two desmopressin formulations are not bioequivalent in children at the currently approved dose levels. Furthermore, the effect of food intake was found to be clinically relevant. Sampling times for a future study were suggested. This sampling design should result in more informative data and consequently generate a more robust model.