Acute intoxication‐type inborn errors of metabolism (IT‐IEM) such as urea cycle disorders and non‐acute IT‐IEM such as phenylketonuria have a major impact on paediatric patients' life. Patients have to adhere to a strict diet but may face neurocognitive impairment and – in acute diseases – metabolic decompensations nevertheless. Research on the subjective burden of IT‐IEM remains sparse. Studies with appropriate sample sizes are needed to make valid statements about health‐related quality of life (HrQoL) in children and adolescents with IT‐IEM. Six international metabolic centres contributed self‐reports and proxy reports of HrQoL (assessed with the Paediatric Quality of Life Inventory) to the final data set (n = 251 patients; age range 2.3‐18.8 years). To compare HrQoL of the patient sample with norm data and between acute and non‐acute IT‐IEM, t tests were conducted. To examine the influence of child age, sex, diagnosis and current dietary treatment on HrQoL, multiple linear regression analyses were conducted. Self‐reports and proxy reporst showed significantly lower HrQoL total scores for children with IT‐IEM compared to healthy children. Current dietary treatment significantly predicted lower proxy reported total HrQoL. Children with non‐acute IT‐IEM reported significantly lower psychosocial health and emotional functioning than children with acute IT‐IEM. The patient sample showed significantly impaired HrQoL and a diet regimen remains a risk factor for lower HrQoL. Differences in HrQoL between acute and non‐acute IT‐IEM subgroups indicate that factors beyond symptom severity determine the perception of disease burden. Identifying these factors is of crucial importance to develop and implement appropriate interventions for those in need.

BackgroundIn recent decades, considerable progress in diagnosis and treatment of patients with intoxication-type inborn errors of metabolism (IT-IEM) such as urea cycle disorders (UCD), organic acidurias (OA), maple syrup urine disease (MSUD), or tyrosinemia type 1 (TYR 1) has resulted in a growing group of long-term survivors. However, IT-IEM still require intense patient and caregiver effort in terms of strict dietetic and pharmacological treatment, and the threat of metabolic crises is always present. Furthermore, crises can affect the central nervous system (CNS), leading to cognitive, behavioural and psychiatric sequelae. Consequently, the well-being of the patients warrants consideration from both a medical and a psychosocial viewpoint by assessing health-related quality of life (HrQoL), psychological adjustment, and adaptive functioning. To date, an overview of findings on these topics for IT-IEM is lacking. We therefore aimed to systematically review the research on HrQoL, psychological adjustment, and adaptive functioning in patients with IT-IEM.MethodsRelevant databases were searched with predefined keywords. Study selection was conducted in two steps based on predefined criteria. Two independent reviewers completed the selection and data extraction.ResultsEleven articles met the inclusion criteria. Studies were of varying methodological quality and used different assessment measures. Findings on HrQoL were inconsistent, with some showing lower and others showing higher or equal HrQoL for IT-IEM patients compared to norms. Findings on psychological adjustment and adaptive functioning were more consistent, showing mostly either no difference or worse adjustment of IT-IEM patients compared to norms. Single medical risk factors for HrQoL, psychological adjustment, or adaptive functioning have been addressed, while psychosocial risk factors have not been addressed.ConclusionData on HrQoL, psychological adjustment, and adaptive functioning for IT-IEM are sparse. Studies are inconsistent in their methodological approaches, assessment instruments and norm populations. A disease-specific standard assessment procedure for HrQoL is not available. Psychosocial risk factors for HrQoL, psychological adjustment, or adaptive functioning have not been investigated. Considering psychosocial variables and their corresponding risk factors for IT-IEM would allow evaluation of outcomes and treatments as well as the planning of effective social and psychological interventions to enhance the patients’ HrQoL.

Introduction: This study is part of the "European network and registry for intoxication type metabolic diseases" (E-IMD) project. Intoxication-type inborn errors of metabolism (IT-IEM) such as urea cycle disorders (UCD) and organic acidurias (OA) have a major impact on patients' lives. Patients have to adhere to strict diet and medication and may suffer from metabolic crises and neurocognitive impairment. Disease-specific health-related quality of life (HrQoL) assessment questionnaires are the method of choice to estimate the subjective burden of a Communicated by: Pascale de Lonlay "Peter Burgard," "Markus A. Landolt," and "Martina Huemer" are contributed equally to this project. Electronic supplementary material:The online version of this chapter

Introduction: Progress in diagnosis and treatment of patients with intoxication-type inborn errors of metabolism (IT-IEM) such as urea cycle disorders, organic acidurias or maple syrup urine disease is resulting in a growing number of long-term survivors. Consequently, health-related quality of life (HrQoL) of patients is increasingly regarded as a meaningful outcome parameter. To develop the first validated, disease-specific HrQoL questionnaire for IT-IEM, patients and parents were interviewed as content experts to identify major physical and psychosocial constraints and resources.Methods: Focus group interviews with 19 paediatric IT-IEM patients and 26 parents were conducted in four metabolic centres in Austria, Germany and Switzerland. Disease-specific HrQoL categories were established by qualitative content analysis.Results: Fourteen disease-specific topics related to the three well-established generic HrQoL dimensions of physi-

BackgroundInborn errors of metabolism (IEM) are a group of rare, heterogeneous and complex genetic conditions. Clinically, IEM often affect the central nervous system and other organs. Some carry the risk of progression and / or potentially life-threatening crises. Many patients have to adhere to lifelong dietary or drug treatment.The complexity of IEM makes it difficult for patients and caregivers to understand their pathophysiology, inheritance and therapy rationale. Especially patients reaching adolescence may have only limited knowledge of their condition since medical care has often entirely been handled by their parents. Knowledge about disease and treatment, however, constitute pillars of self-responsible disease management. Not many standardized patient education materials on IEM are available and their comprehensibility has not been systematically investigated.MethodsWe developed and tested patient education materials for school-aged children and adolescents with IEM. Informative texts and illustrations in paper form and as videos were developed by an international network of metabolic care professionals together with a graphic artist and experts for easy-to-read language. The materials were presented in standardized single or group training sessions to 111 individuals; first, to 74 healthy children and adolescents (recruited via public schools) and consecutively to 37 paediatric patients with IEM (phenylketonuria, galactosemia, urea cycle defects, lysosomal storage disorders) from six metabolic centres. Knowledge-gain was assessed by pre- and post-testing.ResultsKnowledge-gain was significant in healthy children and adolescents as well as in patients (p < .001, r =. -77 /. -70). Effect sizes were large in both groups (r = -.77 / -.70). This result was independent from family language and teacher-rated concentration or cognitive capacity in healthy children.ConclusionThe newly developed patient education materials are a powerful tool to improve disease- and treatment-related knowledge. They facilitate communication between the medical team and children and adolescents with IEM and their caregivers.

Dietary phenylalanine restriction in phenylketonuria (PKU) patients is usually mandatory in order to prevent cognitive impairment. The influence of a low-protein diet on growth has raised concerns in families and caregivers. This paper aims to investigate the growth in PKU patients treated with a low-protein diet including supplementation of amino acids and other nutrients according to standard protocols.We performed a single-center, cross-sectional study on growth in pediatric PKU patients (n = 51) treated with low-protein diet over a 20-month period. Height of healthy siblings (n = 44) and target height, calculated based on parents' height, served as controls.No statistically significant differences were found comparing mean height z-scores between patients and siblings (p = 0.261). Patients <12 years showed a reduction in mean height z-scores compared to the target height (p = 0.020), whereas postpubertal patients ≥12 years did not differ significantly in height z-scores compared to the target height (p = 0.071). Healthy siblings' height did not differ from target height in neither age group (p = 0.100/p = 0.301).Our results suggest that PKU patients treated with low-protein diet can achieve normal growth with patients making up the leeway after puberty. While prepubertal patients were shorter than expected based on their target height, older patients were within their expected target height. This study indicates that current practice of low-protein diet in PKU patients allows normal growth.

Introduction Juvenile idiopathic arthritis (JIA) is the leading chronic rheumatic disease in childhood. To achieve adherence to therapy, in-depth understanding of disease and treatment options are important. Objective Development of specifically designed illustrations and standardised, easy-to-read texts for children and adolescents with JIA. Education materials were tested for comprehensibility and content validity. We hypothesised that children would be able to increase their knowledge about JIA after presentation of materials. Methods The illustrations were designed by a graphic artist and the informative texts consecutively transformed to easy-to-read language. The materials appear as a modular system to allow individualized information for each patient. The illustrations and texts were tested for knowledge gain and improvement of self-efficacy in children affected by JIA/ rheumatic diseases and controls. Health-related quality of life (HRQoL) was tested as an overall assessment of patients’ well-being. Results 46 controls (71% female) and 38 patients (48% female) with a median age of 11 years were tested in a standardised setting. In both groups knowledge gain was significant (controls: t (44) = 11.08, p < 0.001, d = 1.65; patients: t (37) = 7.48, p < 0.001, d = 1.21). The control group had a significantly higher enhancement of disease knowledge compared to patients’ group (p = .046) The follow-up testing was only performed in one school class (20 controls) due to Covid-19 pandemic with significant improvement compared to the pre-test results (p = .002). The enhancement of self-efficacy through the teaching session was significantly higher in the patients’ group. No impairment of HRQoL was seen. Conclusion Explaining juvenile rheumatic diseases and therapeutic strategies is an important task in paediatric rheumatology. To avoid incomprehensible explanations in medical jargon, illustrations and easy-to-read texts were developed. Standardised presentation of the newly created materials resulted in a significant improvement of disease knowledge in patients and controls in addition to an enhancement of self-efficacy in patients.

Background Acute intoxication-type inborn errors of metabolism (IT-IEM) such as urea cycle disorders and non-acute IT-IEM such as phenylketonuria (PKU) and their treatment have a major impact on the life of affected children and families. Yet patients’ and parents’ perspectives on the burdens of IT-IEM and its effects on everyday functioning and well-being have rarely been addressed. Patient- and observer-reported outcomes (PROs/ObsROs) are critically important to evaluate and target health care and treatment efficacy. Therefore, it is mandatory to define PROs/ObsROs relevant to patients with IT-IEM, their families, and health care professionals and to provide valid, standardised and reliable measuring instruments. To achieve consensus we performed a two-round, electronic-based modification of a Delphi survey including 27 parents of affected children, nine teenage patients and 35 health professionals (physicians, nutritionists, psychologists). The final set of PROs/ObsROs was discussed and defined in an online consensus meeting with a subsample of three health professionals, three parents and two patients. For this final set, appropriate measures (PROMs/ObsROMs) were assembled. Results Seventeen PROs/ObsROs constitute the final core set for paediatric IT-IEM. They cover social (e.g. social participation), emotional (e.g. positive affect), and disease-related aspects (e.g. attitude towards treatment) of patients’ lives as well as the experience of parents (e.g. parental stress). Conclusion To promote a holistic treatment approach, this consensus-driven set of relevant PROs/ObsROs should be incorporated into daily IT-IEM care and considered as the key psychological outcomes in clinical trials. We have identified existing—psychometrically and contextual—appropriate PROMs/ObsROMs with open access to facilitate this process.