Assessment and management of nutrition and growth in Rett syndrome

SmartBerry for AI-based growth stage classification and precision nutrition management in strawberry cultivation

Agriculture is vital for human sustenance and economic stability, with increasing global food demand necessitating innovative practices. Traditional farming methods have caused significant environmental damage, highlighting the need for sustainable practices like nutrition management. This paper addresses the emerging integration of artificial intelligence (AI) in agriculture, focusing on the specific challenge of growth stage classification of strawberry plants for optimized nutrition management. While AI has been successfully applied in various agricultural domains, such as plant stress detection and growth monitoring, the precise classification of strawberry growth stages remains underexplored. Accurate growth stage identification is vital for timely nutrient application, directly impacting yield and fruit quality. Our research identifies common gaps in existing literature, including limited or inaccessible datasets, outdated methodologies, and insufficient benchmarking. To overcome these shortcomings, we introduce a robust greenhouse-based dataset covering seven distinct strawberry growth stages, captured under diverse conditions. We then benchmark multiple state-of-the-art models on this dataset, finding that EfficientNetB7 achieves a testing accuracy of 0.837-demonstrating the promise of AI-driven approaches for precise and sustainable nutrient management in horticulture.

Review of a specialist Rett syndrome clinic from 2003 to the COVID pandemic: clinic experience and carer perspectives

BACKGROUND

We have held a 'trouble-shooting' clinic for Rett syndrome patients from 2003 until the COVID pandemic in 2020. The clinic was multidisciplinary, including clinical genetics, paediatric neurology, adult learning disability psychiatry and physiotherapy. Access to specialist communication support and eye-gaze equipment was also often available. We have reviewed the files of patients seen in the clinic and conducted a survey of parents' and carers' satisfaction with the clinic and their experiences during COVID.

RESULTS

Of the 117 patients seen in the clinic, records were reviewed of 103 (97 female, six male) who attended a total of 123 appointments. The records were unavailable for 14 patients. The most common reasons for referral were assessment of 'episodes' of uncertain nature (possibly epileptic, possibly autonomic), the wish for a general review by an experienced team, and questions about the diagnosis. We discuss the nature of the advice we were able to provide and offer some brief case vignettes. We wrote to the parents or carers of all patients seen and 63 respondents were willing to be interviewed about the clinic and their experiences during COVID. Respondents were generally complimentary about the clinic team, emphasising the value of a specialist clinic for those affected by a rare condition. Respondents gave insight into the range of problems experienced during COVID, especially the isolation resulting from the withdrawal of services, demonstrating the value of community support. Some respondents mentioned the shift to remote consultations, which they hoped would continue after COVID for its convenience. However, others talked about how difficult it is in a remote consultation to explain the problems of the affected family member to professionals who do not know the patient or know about Rett syndrome.

CONCLUSIONS

Our findings demonstrate the value of a disease-specific clinic provided by staff experienced with the particular rare condition. Meeting the needs of patients with ultra-rare conditions presents additional challenges. We have also found that the shift to holding a virtual clinic during COVID brought the benefit of convenience but was unsatisfactory in other ways, as it makes clinical assessment more difficult and fails to overcome the sense of isolation during a pandemic.

Rett syndrome

Rett syndrome (RTT) is a severe, progressive, neurodevelopmental disorder, which affects predominantly females. In most cases, RTT is associated with pathogenic variants in MECP2. MeCP2, the protein product of MECP2, is known to regulate gene expression and is highly expressed in the brain. RTT is characterized by developmental regression of spoken language and hand use that, with hand stereotypies and impaired ambulation, constitute the four core diagnostic features. Affected individuals may present multiple other neurological impairments and comorbidities, such as seizures, breathing irregularities, anxiety and constipation. Studies employing neuroimaging, neuropathology, neurochemistry and animal models show reductions in brain size and global decreases in neuronal size, as well as alterations in multiple neurotransmitter systems. Management of RTT is mainly focused on preventing the progression of symptoms, currently improved by guidelines based on natural history studies. Animal and cellular models of MeCP2 deficiency have helped in understanding the pathophysiology of RTT and guided the development of trofinetide, an IGF1-related compound, which is an approved drug for RTT, as well as of other drugs and gene therapies currently under investigation.

Trofinetide for the treatment of Rett syndrome: Results from the open-label extension LILAC study

BACKGROUND

Trofinetide was approved for the treatment of Rett syndrome based on the results of the phase 3, randomized, placebo-controlled, 12-week LAVENDER study. Rett syndrome is a chronic disorder requiring long-term treatment. We report the efficacy and safety results of LILAC, a 40-week, open-label extension study of LAVENDER.

METHODS

Females with Rett syndrome aged 5-21 years received open-label treatment with trofinetide for 40 weeks. The primary endpoint was long-term safety of trofinetide; secondary endpoints included the change from baseline at week 40 in the Rett Syndrome Behaviour Questionnaire score and the Clinical Global Impression-Improvement score at week 40.

FINDINGS

Overall, 154 participants were enrolled and treated with trofinetide in LILAC. The most common adverse events in LILAC were diarrhea (74.7%), vomiting (28.6%), and COVID-19 (11.0%). Diarrhea was the most common adverse event leading to treatment withdrawal (21.4%). The Rett Syndrome Behaviour Questionnaire mean score (standard error) improvement from the LAVENDER baseline to week 40 in LILAC was -7.3 (1.62) and -7.0 (1.61) for participants treated with trofinetide and placebo in LAVENDER, respectively. Mean Clinical Global Impression-Improvement scores (standard error) at week 40 rated from the LILAC baseline were 3.1 (0.11) and 3.2 (0.14) for participants treated with trofinetide and placebo in LAVENDER, respectively.

CONCLUSIONS

Treatment with trofinetide for ≤40 weeks continued to improve symptoms of Rett syndrome. Trofinetide had a similar safety profile in LILAC as in LAVENDER.

FUNDING

The study was supported by Acadia Pharmaceuticals Inc. (San Diego, CA, USA). This trial was registered at ClinicalTrials.gov (NCT04279314).

Management of respiratory issues in patients with Rett syndrome: Italian experts' consensus using a Delphi approach

BACKGROUND

Despite the publication of the 2020 guidelines on how to manage Rett Syndrome (RS), some fundamental topics are still open, in particular respiratory problems.

OBJECTIVE

Identification and reinforcement of current recommendations concerning the management of respiratory issues in RS patients.

MATERIALS AND METHODS

Using a Delphi approach, the leading group reviewed the literature and formulated 14 statements. A multidisciplinary panel of 29 experts were invited to score, for each statement, their agreement on a 1-5 scale. The cut-off level for consensus was 75%, obtained through multiple rounds.

RESULTS

The panel agreed that in all RS types, respiratory issues should be faced at an early stage, regardless of epilepsy onset. It is recommended to perform periodically sleep studies in all Congenital Rett Syndrome, and in selected cases with other RS types. Noninvasive ventilation should be considered in all RS subjects with sleep respiratory disorders and in those with hypotonia associated with hypercapnia. Chest physiotherapy should be performed in all RS patients with difficult management of the accumulation of respiratory secretions, using airway clearance techniques and devices (PEP-mask, AMBU bag, or cough machine), more appropriate and tolerated by the patients. The panel recommended individualized programs for the management of scoliosis, and to consider performing gastrostomy in patients at increased risk of ab ingestis pneumonia.

CONCLUSIONS

This consensus could support everyday clinical practice on respiratory issues in RS patients, complementary to existing recommendations by regulatory agencies and guidelines.

Fiberoptic Endoscopic Evaluation of Swallowing Findings in Children With Rett Syndrome

Feeding abnormalities, swallowing dysfunction, and gastrointestinal issues cause poor weight gain, oral motor dysfunction, and air swallowing in children with Rett syndrome (RTT). Pneumonia is the leading cause of death. Our study describes fiberoptic endoscopic swallowing findings in 11 female RTT children. Each patient was evaluated using the 8-point Penetration/Aspiration Scale (PAS). The average age was 7 years. All patients had tongue dyskinesis and prolonged oral stage. Eight girls exhibited liquid entering the airway without coughing, whereas 6 did well with pureed meal. Three girls had pneumonia. Age was not correlated with pneumonia episodes (P = .18). Pureed material was related with pneumonia (P = .006), whereas liquids were not. Pureed PAS was positively correlated with Liquid PAS (P = .008) and age (P = .004). All aspiration/penetration incidents occurred before the pharyngeal phase. No patient under 7 years experienced pneumonia episodes. Silent aspiration can occur early in infancy, although pneumonia episodes can occur later.

The use of botulinum toxin for grinding in patients with Rett syndrome-Case report

AIMS

Rett syndrome (RTT) is a neurodevelopmental disorder caused by a mutation in the methyl-CpG-binding protein 2 (MECP2) gene. It is characterized by profound and severe motor disability. Patients with RTT grind their teeth, causing damage to their permanent teeth. This article aims to describe the case of an 8-year-old child with RTT and the methods of botulinum toxin-based treatment for teeth grinding.

METHODS AND RESULTS

Surface electromyography (sEMG) was used to monitor the effects of treatment. The masseter and temporal muscles, responsible for the elevation of the mandible, were injected with botulinum toxin. The results of the sEMG examination performed 1 week, 1 month and 4 months after toxin administration were compared to the sEMG conducted before treatment. The research demonstrates a significant reduction in both grinding frequency and tension of the masseter and temporal muscles.

CONCLUSION

Possible adverse effects after chronic use of botulinum toxin were discussed. The article also emphasizes the need for masticatory muscle rehabilitation during botulinum toxin therapy. However, it is necessary to repeat this procedure on a larger group of children with RTT to establish our efforts' efficacy.

Improving care for rare genetic neurodevelopmental disorders: A systematic review and critical appraisal of clinical practice guidelines using AGREE II

PURPOSE

Rare genetic neurodevelopmental disorders associated with intellectual disability require lifelong multidisciplinary care. Clinical practice guidelines may support healthcare professionals in their daily practice, but guideline development for rare conditions can be challenging. In this systematic review, the characteristics and methodological quality of internationally published recommendations for this population are described to provide an overview of current guidelines and inform future efforts of European Reference Network ITHACA (Intellectual disability, TeleHealth, Autism, and Congenital Anomalies).

METHODS

MEDLINE, Embase, and Orphanet were systematically searched to identify guidelines for conditions classified as "rare genetic intellectual disability" (ORPHA:183757). Methodological quality was assessed using the Appraisal of Guidelines, Research, and Evaluation II tool.

RESULTS

Seventy internationally published guidelines, addressing the diagnosis and/or management of 28 conditions, were included. The methodological rigor of development was highly variable with limited reporting of literature searches and consensus methods. Stakeholder involvement and editorial independence varied as well. Implementation was rarely addressed.

CONCLUSION

Comprehensive, high-quality guidelines are lacking for many rare genetic neurodevelopmental disorders. Use and transparent reporting of sound development methodologies, active involvement of affected individuals and families, robust conflict of interest procedures, and attention to implementation are vital for enhancing the impact of clinical practice recommendations.

Secondary bruxism: A valid diagnosis or just a coincidental finding of additional masticatory muscle activity? A narrative review of literature

INTRODUCTION

Bruxism is defined as a repetitive masticatory muscle activity that can manifest it upon awakening (awake bruxism-AB) or during sleep (sleep bruxism-SB). Some forms of both, AB and SB can be associated to many other coexistent factors, considered of risk for the initiation and maintenance of the bruxism. Although controversial, the term 'secondary bruxism' has frequently been used to label these cases. The absence of an adequate definition of bruxism, the non-distinction between the circadian manifestations and the report of many different measurement techniques, however, are important factors to be considered when judging the literature findings. The use (and abuse) of drugs, caffeine, nicotine, alcohol and psychoactive substances, the presence of respiratory disorders during sleep, gastroesophageal reflux disorders and movement, neurological and psychiatric disorders are among these factors. The scarcity of controlled studies and the complexity and interactions among all aforementioned factors, unfortunately, does not allow to establish any causality or temporal association with SB and AB. The supposition that variables are related depends on different parameters, not clearly demonstrated in the available studies.

OBJECTIVES

This narrative review aims at providing oral health care professionals with an update on the co-risk factors and disorders possibly associated with bruxism. In addition, the authors discuss the appropriateness of the term 'secondary bruxism' as a valid diagnostic category based on the available evidence.

CONCLUSION

The absence of an adequate definition of bruxism, the non-distinction between the circadian manifestations and the report of many different measurement techniques found in many studies preclude any solid and convincing conclusion on the existence of the 'secondary' bruxism.

The Efficacy of a Human-Ready miniMECP2 Gene Therapy in a Pre-Clinical Model of Rett Syndrome

Inactivating mutations and the duplication of methyl-CpG binding protein 2 (MeCP2), respectively, mediate Rett syndrome (RTT) and MECP2 duplication syndrome. These disorders underscore the conceptual dose-dependent risk posed by MECP2 gene therapy for mosaic RTT patients. Recently, a miRNA-Responsive Autoregulatory Element (miRARE) mitigated the dose-dependent toxicity posed by self-complementary adeno-associated viral vector serotype 9 (AAV9) miniMECP2 gene therapy (scAAV9/miniMECP2-myc) in mice. Here, we report an efficacy assessment for the human-ready version of this regulated gene therapy (TSHA-102) in male Mecp2-/y knockout (KO) mice after intracerebroventricular (ICV) administration at postnatal day 2 (P2) and after intrathecal (IT) administration at P7, P14 (±immunosuppression), and P28 (±immunosuppression). We also report qPCR studies on KO mice treated at P7-P35; protein analyses in KO mice treated at P38; and a survival safety study in female adult Mecp2-/+ mice. In KO mice, TSHA-102 improved respiration, weight, and survival across multiple doses and treatment ages. TSHA-102 significantly improved the front average stance and swing times relative to the front average stride time after P14 administration of the highest dose for that treatment age. Viral genomic DNA and miniMECP2 mRNA were present in the CNS. MiniMeCP2 protein expression was higher in the KO spinal cord compared to the brain. In female mice, TSHA-102 permitted survivals that were similar to those of vehicle-treated controls. In all, these pivotal data helped to support the regulatory approval to initiate a clinical trial for TSHA-102 in RTT patients (clinical trial identifier number NCT05606614).

A Severity Comparison between Italian and Israeli Rett Syndrome Cohorts

Rett syndrome (RTT) is a neurodevelopmental disorder marked by profound cognitive, communication, and motor impairments. Despite identified genotype/phenotype connections, the extent of clinical severity varies even among individuals sharing the same genetic mutation. Diverse sociocultural environments, such as the level of inclusivity of the scholar system, the time spent with family, and the intensity of the rehabilitative intervention provided, might influence their development diversely. This study examines the severity of RTT in people in Italy and Israel, countries with distinct contradictory approaches to caring for those with intricate disabilities, across two age groups. Data from 136 Italian and 59 Israeli girls and women with RTT were assessed and divided into two age categories: above and below 12 years. The RARS, a standardized RTT-specific clinical severity tool, was administered. Despite no differences in age and genetic characteristics, the Italian group showed better scores in the RARS motor and disease-related characteristics areas in both age groups. Moreover, the young Italian participants gathered better total RARS scores and emotional and behavioral characteristics area scores. Furthermore, the young group showed significantly less scoliosis, foot problems, and epilepsy than the older group. These findings endorse the inclusion of girls with RTT in the regular schooling system for a limited daily period, investing in high activity levels within the home and community environments, and suggest continuously providing the person with daily occasions of physical activity and socialization.

Multidisciplinary Management of Rett Syndrome: Twenty Years' Experience

Over the last 20 years, the understanding and natural history of Rett syndrome has advanced, but to date no cure has emerged, with multidisciplinary management being symptomatic and supportive. This study provides a comprehensive review of the clinical features, comorbidities and multidisciplinary management of a well-characterized cohort of females with classical Rett syndrome. We aim to improve awareness and understanding of Rett syndrome amongst pediatricians, pediatric subspecialists and allied health professionals to enable early diagnosis and a streamlined enrolment approach for future clinical trials. Rett syndrome, a complex X-linked condition, affecting mainly females, is due to pathogenic variants of the MECP2 gene in most affected individuals. The Rett syndrome Multidisciplinary Management clinic at The Children's Hospital at Westmead, Sydney, Australia, was established in 2000. This retrospective analysis of individuals who attended the clinic from 2000 to 2020 was performed to identify the incidence and predicted age of onset of Rett syndrome related comorbidities, disease progression and to review management principles. Data collected included age of Rett syndrome diagnosis, MECP2 genotype, clinical features and medical comorbidities, such as sleep disturbance, seizures, breathing irregularities, scoliosis, mobility, hand stereotypies, hand function, constipation, feeding ability, use of gastrostomy, communication skills, QTc prolongation, anthropometry, and bruxism. Analysis of 103 girls who fulfilled the clinical diagnostic criteria for classical Rett syndrome with a pathogenic variant of the MECP2 gene showed a median age of diagnosis of 3 years. The most frequent MECP2 variant was c.502 C>T.

Diet and Nutritional Status of Polish Girls with Rett Syndrome-A Case-Control Study

(1) Background: Rett syndrome may be considered a disease strongly associated with nutritional disorders that are likely to require special management strategies, extending beyond what is usually required for children with other developmental disorders. The aim of the study was to assess the nutritional status and diet of Polish girls with Rett syndrome. (2) Methods: Each patient (study group = 49, control group = 22) underwent anthropometric measurements, including body weight and height, waist, hip and arm circumference, and skinfold measurement. The assessment of the diet was based on the analysis of 7-day menus and the Food Frequency Questionnaire (FFQ-6). Data were analyzed using Statistica 13.3. (3) Results: The majority of the girls with Rett syndrome were deficient in weight and height, and consumed fewer calories, less protein, dietary fiber, calcium, and iron than the control group. They also drank less fluid. Soft products that were easy to chew and considered to be high in energy value were significantly more common in the menus. (4) Conclusions: Girls with Rett syndrome are characterized by weight deficiencies, poor growth that deteriorates with age, and are at risk of food shortages. Various nutritional intervention strategies should be explored to reduce and, if possible, prevent malnutrition and cachexia in such patients.

Rett Syndrome: A Tale of Altered Genetics, Synaptic Plasticity, and Neurodevelopmental Dynamics

Rett syndrome (RTT) is a neurodevelopmental disorder that is a leading cause of severe cognitive and physical impairment. RTT typically occurs in females, although rare cases of males with the disease exist. Its genetic cause, symptoms, and clinical progression timeline have also become well-documented since its initial discovery. However, a relatively late diagnosis and lack of an available cure signify that our understanding of the disease is incomplete. Innovative research methods and tools are thereby helping to fill gaps in our knowledge of RTT. Specifically, mouse models of RTT, video analysis, and retrospective parental analysis are well-established tools that provide valuable insights into RTT. Moreover, current and anticipated treatment options are improving the quality of life of the RTT patient population. Collectively, these developments are creating optimistic future perspectives for RTT.

Impact of Genetic and Genomic Testing on the Clinical Management of Patients with Autism Spectrum Disorder

Research has shown that genetics play a key role in the development of autism spectrum disorder (ASD). ASD has been linked to many genes and is a prominent feature in numerous genetic disorders. A genetic evaluation should be offered to any patient who receives a diagnosis of ASD, including deep phenotyping and genetic testing when clinically indicated. When insurance does not cover genetic testing for ASD patients, the lack of medical utility is often cited as a reason for prior authorization request denial. However, ample evidence exists that genetic testing has the power to change clinical management in many of these patients. Genetic testing that results in a diagnosis guides clinicians to screen for associated medical conditions and can direct targeted medical interventions. Given the potential for clinically actionable results, it is important that genetic testing be available and accessible to all patients with ASD.

Improving clinical trial readiness to accelerate development of new therapeutics for Rett syndrome

Rett syndrome is associated with severe functional impairments and many comorbidities, each in urgent need of treatments. Mutations in the MECP2 gene were identified as causing Rett syndrome in 1999. Over the past 20 years there has been an abundance of preclinical research with some studies leading to human clinical trials. Despite this, few viable therapeutic options have emerged from this investment of effort. Reasons for this lack of success as they relate both to preclinical research and the clinical trial landscape are discussed. Considering what needs to be done to promote further success in the field, we take a positive and constructive approach and introduce the concept of clinical trial readiness and its necessary ingredients for Rett syndrome. These include: listening to the needs of families; support from advocacy groups; optimising use of existing clinic infrastructures and available natural history data; and, finally, the validation of existing outcome measures and/or the development and validation of new measures. We conclude by reiterating the need for a collaborative and coordinated approach amongst the many different stakeholder groups and the need to engage in new types of trial design which could be much more efficient, less costly and much less burdensome on families.

Clinical presentation of Rett syndrome in relation to quality of life and family functioning

Objective

Rett syndrome (RTT) is a chronic condition that manifest in young children, with concomitant comorbidities such as respiratory problems, scoliosis, epilepsy, and malnutrition, which may affect children’s quality of life (QoL) and family functioning. The objective of this cross-sectional descriptive correlation study was to understand the clinical presentation of RTT in relation to QoL and family functioning.

Methods

We included 23 parents of children with RTT. In this study, we used the PedsQL™ Family Impact Module, the Pediatric Quality of Life Inventory 4.0 generic core scales (PedsQL™ 4.0), and an author-designed questionnaire to assess QoL and family functioning.

Results

A significant relationship was observed between PedsQL™ 4.0 score and child’s age in the physical functioning dimension. Children aged 8 to 12 years demonstrated significantly higher scores than those in the other age groups. Malnutrition in the child significantly affected functioning of the family in the family relationships dimension. Children receiving 5 hours of rehabilitation treatment a week had significantly higher QoL in the school functioning dimension.

Conclusions

QOL in children with RTT, as perceived by their parents, is reduced. RTT has a significant negative correlation with family functioning.

Dietary intake and growth deficits in Rett syndrome-A cross-section study

Growth deficit is a common comorbidity and one of the supportive criteria in Rett syndrome (RTT). This study aimed to investigate the impact of dystonia, dietary intakes, and clinical severities on growth patterns in a Taiwanese cohort of RTT. We recruited 44 RTT patients with MECP2 mutation for analysis. For individuals ≤18 years of age, in comparison to the RTT-specific growth chart which comprised American RTT cohort, the body height was right-shifted to a higher percentile, whereas the body weight was left-shifted to a lower percentile. Furthermore, the body mass index was significantly decreased when compared to RTT-specific growth chart (p = 0.01). Higher degree of overall disease severity (odd ratio = 1.159; 95% CI = 1.063-1.264; p = 0.001) and hand use impairment (odd ratio = 2.017; 95% CI = 1.037, 3.921; p = 0.039) were associated with more severe growth patterns. All individuals had dystonia at certain variable degrees. The dystonia worsened with age (p < 0.001) but did not have significant impact on growth deficit. Most of our cohort had adequate protein (97.37%) and energy (58.97%) intakes. The fiber intakes were generally low, with about 38 (97.4%) individuals did not meet the daily reference intakes of fiber. The protein intake was significantly lower in individuals with severe growth deficit (p = 0.04). Our study shows that ethnicity should be considered when comparing RTT individuals' growth pattern to the RTT-specific growth chart. Further, disease severity, genotypes, and nutrition exert important impacts on RTT-growth pattern. LAY SUMMARY: Growth impairment is an important issue in Rett syndrome and the underlying patho-mechanism is multifactorial. Higher degree of overall disease severity and hand use impairment were associated with more severe growth pattern deficits. Although all individuals had dystonia at certain variable degrees and the dystonia worsened with age, but it did not have significant impact on growth deficit. Nutritional intakes may partially affect growth. Furthermore, ethnicity should be considered when comparing RTT individuals' growth pattern to the RTT-specific growth chart.

Oral Manifestations of Rett Syndrome-A Systematic Review

Rett Syndrome is an x linked developmental disorder which becomes apparent in females after 6 to 18 months of age. It leads to severe impairments including loss of speech, loss of hand movements/manual dexterity, characteristic hand movements such as hang wringing and intellectual disability/learning problems. This systematic review was carried out to identify the dental manifestation of Rett syndrome and to shed light on treatment options available for oral health problems associated with Rett syndrome. A systematic literature search was conducted on the PubMed, Scopus, Biomed, Web of Science, Embase, Google Scholars, Cochrane and CINAHL using the following entries: Rett syndrome (n = 3790), Oral health and Rett syndrome (n = 17), dental health of Rett syndrome patients (n = 13), and the MeSH terms listed below: Rett syndrome and Oral Health (n = 17), Rett syndrome and dentistry (n = 29). The final review included 22 search articles. The most common oral findings was bruxism. Masseteric hypertrophy was also reported. Anterior open bite and non-physiological tooth wear was observed. Other oral manifestations of Rett syndrome included mouth breathing, tongue thrusting, digit/thumb sucking, high arch palate. Increased awareness and dental education amongst dentists and assistants regarding the dental manifestations of Rett syndrome and similar neurodevelopmental disorders is required to improve the level of care and empathy they can provide to these differently able patients. Research on dental aspects of Rett is scarce and this remains a neglected topic.

Development of consensus-based guidelines for managing communication of individuals with Rett syndrome

Difficulties with communication have a profound impact on the lives of individuals with Rett syndrome and their caregivers. Globally, many families report difficulty accessing appropriate and timely information and services from professionals with expertise in augmentative and alternative communication (AAC) as it pertains to Rett syndrome. To address this need, international consensus-based guidelines for managing the communication of individuals with Rett syndrome were developed by combining available evidence and lived experience with expert opinion. A two-phase Delphi survey was built on statements and recommendations extracted from a review of over 300 pieces of literature combined with survey responses from communication professionals and caregivers. All statements that reached a pre-determined threshold of ≥70% agreement were incorporated into guidelines that consist of 268 statements and recommendations relating to (a) rights of the individual; (b) beliefs and attitudes of communication partners; (c) professional knowledge and team work; (d) strategies to optimize engagement; (e) assessment; and (f) intervention (targets and goals, techniques), including the use of AAC. To date, this project is the largest of its kind, with 650 participants from 43 countries contributing to development of consensus-based guidelines for Rett syndrome.

Medical Issues in Adults with Rett Syndrome - A National Survey

Objectives: To examine main health issues in a population of females with Rett syndrome, with a focus on individuals aged 36 or older. Methods: A national survey including 85 females, divided into a younger (1-20 years), a middle (21-35 years) and an older group (36-66 years). Data include clinical examination, medical records and parental interviews. Prevalences of six main medical issues (scoliosis, ambulation, growth, respiration, gastrointestinal dysmobility and epilepsy) and severity scores in the three groups were compared. Results: Mean severity scores were 11.8, 15.1 and 13.7 (from younger to older), and the difference between the younger and the middle group was significant. No other major significant prevalence differences were observed. Conclusions: Most main medical issues in Rett syndrome continued to be a major concern in adulthood, but health did not seem to decline with increasing age. The results emphasize the need for clinical follow-up throughout adulthood.

Consensus guidelines on managing Rett syndrome across the lifespan

BACKGROUND

Rett syndrome (RTT) is a severe neurodevelopmental disorder with complex medical comorbidities extending beyond the nervous system requiring the attention of health professionals. There is no peer-reviewed, consensus-based therapeutic guidance to care in RTT. The objective was to provide consensus on guidance of best practice for addressing these concerns.

METHODS

Informed by the literature and using a modified Delphi approach, a consensus process was used to develop guidance for care in RTT by health professionals.

RESULTS

Typical RTT presents early in childhood in a clinically recognisable fashion. Multisystem comorbidities evolve throughout the lifespan requiring coordination of care between primary care and often multiple subspecialty providers. To assist health professionals and families in seeking best practice, a checklist and detailed references for guidance were developed by consensus.

CONCLUSIONS

The overall multisystem issues of RTT require primary care providers and other health professionals to manage complex medical comorbidities within the context of the whole individual and family. Given the median life expectancy well into the sixth decade, guidance is provided to health professionals to achieve current best possible outcomes for these special-needs individuals.

Oral health experiences of individuals with Rett syndrome: a retrospective study

Background

There is relatively little literature on the oral health experiences of individuals with Rett syndrome. This study described the incidence of dental extractions and restorations in a population-based cohort, according to a range of demographic and clinical factors. The association between bruxism and age was also investigated.

Methods

Existing questionnaire data in the population-based Australian Rett Syndrome Database for the years 2004, 2006, 2009 or 2011 on genetically confirmed female cases (n = 242) were analysed.

Results

The incidence rate of restorations and extractions were 6.8 per 100 person years (py) and 9.3 per 100 py respectively. The incidence of extractions decreased with increasing levels of income. Compared to those with a C-terminal mutation, the incidence rate of extraction was higher for those with large deletions (Incidence Rate Ratio (IRR) 4.93; 95% CI 1.46–16.7, p = 0.01). There was a 5% decrease in the risk of frequent bruxism for every one-year increase in age (Risk Ratio 0.95; 95% CI 0.94–0.97).

Conclusions

Social advantage may provide some protection for dental health in individuals with Rett syndrome. Those with more severe genotypes seemed to have poorer oral health outcomes.

The course of awake breathing disturbances across the lifespan in Rett syndrome

Rett syndrome (RTT), an X-linked dominant neurodevelopmental disorder caused by mutations in MECP2, is associated with a peculiar breathing disturbance exclusively during wakefulness that is distressing, and can even prompt emergency resuscitation. Through the RTT Natural History Study, we characterized cross sectional and longitudinal characteristics of awake breathing abnormalities in RTT and identified associated clinical features. Participants were recruited from 2006 to 2015, and cumulative lifetime prevalence of breathing dysfunction was determined using the Kaplan-Meier estimator. Risk factors were assessed using logistic regression. Of 1205 participants, 1185 had sufficient data for analysis, including 922 females with classic RTT, 778 of whom were followed longitudinally for up to 9.0 years, for a total of 3944 person-years. Participants with classic or atypical severe RTT were more likely to have breathing dysfunction (nearly 100% over the lifespan) compared to those with atypical mild RTT (60-70%). Remission was common, lasting 1 year on average, with 15% ending the study in terminal remission. Factors associated with higher odds of severe breathing dysfunction included poor gross and fine motor function, frequency of stereotypical hand movements, seizure frequency, prolonged corrected QT interval on EKG, and two quality of life metrics: caregiver concern about physical health and contracting illness. Factors associated with lower prevalence of severe breathing dysfunction included higher body mass index and head circumference Z-scores, advanced age, and severe scoliosis or contractures. Awake breathing dysfunction is common in RTT, more so than seizures, and is associated with function, quality of life and risk for cardiac dysrhythmia.

Revised consensus statement on the preventive and symptomatic care of patients with leukodystrophies

Leukodystrophies are a broad class of genetic disorders that result in disruption or destruction of central myelination. Although the mechanisms underlying these disorders are heterogeneous, there are many common symptoms that affect patients irrespective of the genetic diagnosis. The comfort and quality of life of these children is a primary goal that can complement efforts directed at curative therapies. Contained within this report is a systems-based approach to management of complications that result from leukodystrophies. We discuss the initial evaluation, identification of common medical issues, and management options to establish a comprehensive, standardized care approach. We will also address clinical topics relevant to select leukodystrophies, such as gallbladder pathology and adrenal insufficiency. The recommendations within this review rely on existing studies and consensus opinions and underscore the need for future research on evidence-based outcomes to better treat the manifestations of this unique set of genetic disorders.

A case-controlled comparison of postoperative analgesic dosing between girls with Rett syndrome and girls with and without developmental disability undergoing spinal fusion surgery

BACKGROUND

Rett syndrome is associated with severe motor and communicative impairment making optimal postoperative pain management a challenge. There are case reports documenting reduced postoperative analgesic requirement in Rett syndrome.

AIM

The goal of this preliminary investigation was to compare postoperative analgesic management among a sample of girls with Rett syndrome compared to girls with and without developmental disability undergoing spinal fusion surgery.

METHOD

The medical records of eight girls with Rett syndrome (mean age = 13.2 years, sd = 1.9), eight girls with developmental disability (cerebral palsy; mean age = 13.1 years, sd = 2.0), and eight girls without developmental disability (adolescent idiopathic scoliosis; mean age = 13.4, sd = 1.8) were reviewed. Data related to demographics, medications, and route of drug administration were recorded.

RESULTS

Girls with Rett syndrome received significantly fewer morphine equivalent opioids postoperatively (M = 0.26 mg·kg^-1 ·day^-1 , sd = 0.10) compared to girls with adolescent idiopathic scoliosis (M = 0.47mg·kg^-1 ·day^-1 , sd = 0.13; 95% CI -0.34 to -0.08; P = 0.001) and girls with CP (M = 0.40 mg·kg^-1 per day, sd = 0.14; 95% CI -0.27 to -0.02; P = 0.01). Girls with Rett syndrome received significantly fewer opioid patient-controlled analgesic (PCA) bolus doses (given by proxy; M = 42.63, sd = 17.84) compared to girls with adolescent idiopathic scoliosis (M = 98.25, sd = 52.77; 95% CI -96.42 to -14.83; P = 0.01). There was also some evidence indicating girls with Rett syndrome received fewer bolus doses compared to girls with CP (M = 80.88, sd = 38.93; 95% CI -79.05 to 2.55; P = 0.06). On average, girls with Rett syndrome also received smaller total doses of acetaminophen, diazepam, and hydroxyzine.

CONCLUSION

This study highlights possible discrepancies in postoperative pain management specific to girls with Rett syndrome and suggests further investigation is warranted to determine best practice for postoperative analgesic management for this vulnerable patient population.

Longitudinal course of epilepsy in Rett syndrome and related disorders

Epilepsy is common in Rett syndrome, an X-linked dominant disorder caused by mutations in the MECP2 gene, and in Rett-related disorders, such as MECP2 duplication. However, neither the longitudinal course of epilepsy nor the patterns of seizure onset and remission have been described in Rett syndrome and related conditions. The present study summarizes the findings of the Rett syndrome Natural History study. Participants with clinical Rett syndrome and those with MECP2 mutations without the clinical syndrome were recruited through the Rett Natural History study from 2006 to 2015. Clinical details were collected, and cumulative lifetime prevalence of epilepsy was determined using the Kaplan-Meier estimator. Risk factors for epilepsy were assessed using Cox proportional hazards models. Of 1205 participants enrolled in the study, 922 had classic Rett syndrome, and 778 of these were followed longitudinally for 3939 person-years. The diagnosis of atypical Rett syndrome with a severe clinical phenotype was associated with higher prevalence of epilepsy than those with classic Rett syndrome. While point prevalence of active seizures ranged from 30% to 44%, the estimated cumulative lifetime prevalence of epilepsy using Kaplan-Meier approached 90%. Specific MECP2 mutations were not significantly associated with either seizure prevalence or seizure severity. In contrast, many clinical features were associated with seizure prevalence; frequency of hospitalizations, inability to walk, bradykinesia, scoliosis, gastrostomy feeding, age of seizure onset, and late age of diagnosis were independently associated with higher odds of an individual having epilepsy. Aggressive behaviour was associated with lower odds. Three distinct patterns of seizure prevalence emerged in classic Rett syndrome, including those who did not have seizures throughout the study, those who had frequent relapse and remission, and those who had relentless seizures. Although 248 of those with classic Rett syndrome and a history of seizures were in terminal remission at last contact, only 74 (12% of those with a history of epilepsy) were seizure free and off anti-seizure medication. When studied longitudinally, point prevalence of active seizures is relatively low in Rett syndrome, although lifetime risk of epilepsy is higher than previously reported. While daily seizures are uncommon in Rett syndrome, prolonged remission is less common than in other causes of childhood onset epilepsy. Complete remission off anti-seizure medications is possible, but future efforts should be directed at determining what factors predict when withdrawal of medications in those who are seizure free is propitious.

Clinical and biological progress over 50 years in Rett syndrome

In the 50 years since Andreas Rett first described the syndrome that came to bear his name, and is now known to be caused by a mutation in the methyl-CpG-binding protein 2 (MECP2) gene, a compelling blend of astute clinical observations and clinical and laboratory research has substantially enhanced our understanding of this rare disorder. Here, we document the contributions of the early pioneers in Rett syndrome (RTT) research, and describe the evolution of knowledge in terms of diagnostic criteria, clinical variation, and the interplay with other Rett-related disorders. We provide a synthesis of what is known about the neurobiology of MeCP2, considering the lessons learned from both cell and animal models, and how they might inform future clinical trials. With a focus on the core criteria, we examine the relationships between genotype and clinical severity. We review current knowledge about the many comorbidities that occur in RTT, and how genotype may modify their presentation. We also acknowledge the important drivers that are accelerating this research programme, including the roles of research infrastructure, international collaboration and advocacy groups. Finally, we highlight the major milestones since 1966, and what they mean for the day-to-day lives of individuals with RTT and their families.

Neurobiologically-based treatments in Rett syndrome: opportunities and challenges

Introduction: Rett syndrome (RTT) is an X-linked neurodevelopmental disorder that primarily affects females, typically resulting in a period of developmental regression in early childhood followed by stabilization and severe chronic cognitive, behavioral, and physical disability. No known treatment exists beyond symptomatic management, and while insights into the genetic cause, pathophysiology, neurobiology, and natural history of RTT have been gained, many challenges remain. Areas covered: Based on a comprehensive survey of the primary literature on RTT, this article describes and comments upon the general and unique features of the disorder, genetic and neurobiological bases of drug development, and the history of clinical trials in RTT, with an emphasis on drug trial design, outcome measures, and implementation. Expert opinion: Neurobiologically based drug trials are the ultimate goal in RTT, and due to the complexity and global nature of the disorder, drugs targeting both general mechanisms (e.g., growth factors) and specific systems (e.g., glutamate modulators) could be effective. Trial design should optimize data on safety and efficacy, but selection of outcome measures with adequate measurement properties, as well as innovative strategies, such as those enhancing synaptic plasticity and use of biomarkers, are essential for progress in RTT and other neurodevelopmental disorders.

Progress in Rett Syndrome: from discovery to clinical trials

Fifty years ago, Andreas Rett described a disorder in 22 females featuring prominent regression of fine motor and communication skills, cognitive impairment, stereotypic movements, periodic breathing, and gait abnormalities. This disorder became known as Rett syndrome (RTT) following the report of Hagberg et al. in 1983. Although RTT was scarcely recognized at that time in the United States, here the efforts of Rett and Hagberg led to rapid progress in recognition and diagnosis, a clearer understanding of its clinical and pathological underpinnings, and, ultimately, identification of mutations in the methyl-CpG-binding protein 2 (MECP2) gene as the primary cause of this unique and challenging neurodevelopmental disorder. Thereafter, a natural history study and critical translational research in animal models paved the way for potential disease-modifying agents to be assessed in human clinical trials. To be successful, the energies of the international community at all levels, including researchers in clinical and basic science, funding agencies, pharmaceutical companies, patient advocates, and, above all, parents and their children are essential. Otherwise, hopes for effective treatment, if not, a cure, will remain unfulfilled.

Quantitative and qualitative insights into the experiences of children with Rett syndrome and their families

Rett syndrome is a rare neurodevelopmental disorder caused by a mutation in the MECP2 gene. It is associated with severe functional impairments and medical comorbidities such as scoliosis and poor growth. The population-based and longitudinal Australian Rett Syndrome Database was established in 1993 and has supported investigations of the natural history of Rett syndrome and effectiveness of treatments, as well as a suite of qualitative studies to identify deeper meanings. This paper describes the early presentation of Rett syndrome, including regression and challenges for families seeking a diagnosis. We discuss the importance of implementing strategies to enhance daily communication and movement, describe difficulties interpreting the presence of pain and discomfort, and argue for a stronger evidence base in relation to management. Finally, we outline a framework for understanding quality of life in Rett syndrome and suggest areas of life to which we can direct efforts in order to improve quality of life. Each of these descriptions is illustrated with vignettes of child and family experiences. Clinicians and researchers must continue to build this framework of knowledge and understanding with efforts committed to providing more effective treatments and supporting the best quality of life for those affected.

How can clinical ethics guide the management of comorbidities in the child with Rett syndrome?

Rett syndrome is a rare disorder caused by a mutation in the MECP2 gene. Those affected generally have severe functional impairments, and medical comorbidities such as scoliosis and poor growth are common. There is a paucity of information on the natural history of many rare disorders and an even greater deficit of evidence to guide best practice. The population-based and longitudinal Australian Rett Syndrome Database established in 1993 has supported investigations of the natural history of Rett syndrome and effectiveness of treatments. This paper reviews the disorder Rett syndrome and evidence for the management of scoliosis and poor growth within a clinical ethics framework. Compared with conservative management, we have shown that spinal fusion is associated with reduced mortality and better respiratory health. We have also shown that gastrostomy insertion is associated with subsequent weight gain. Family counselling for both procedures necessarily must include family perspectives and careful clinical attention to their needs and wishes. Vignettes describing family decision-making and experiences are presented to illustrate the principals of beneficence and autonomy in determining the best interests of the child and family. A blend of evidence-based practice with a strong clinical ethics framework has capacity to build existing strengths in families and reduce the negative impacts of disability and in so doing, optimise the health and wellbeing of those with Rett syndrome.

Rett Syndrome Turns 50: Themes From a Chronicle: Medical Perspectives and the Human Face of Rett Syndrome

BACKGROUND

Fifty years ago Andreas Rett first described in great detail what came to be known as "Rett syndrome." Understanding girls and women with this syndrome and their families helped in many ways to revolutionize modern neurodevelopmental medicine. For some people the identification of the genetic underpinning of the syndrome and the ongoing biological research into this condition represented the peak of the scientific accomplishments in Rett syndrome. For others, it was developments in clinical research methodologies that were especially important. Above all, the patient- and family-oriented empathetic and collaborative approach to care by professionals collaborating with families has led to immense achievements, both scientific and humanistic.

AIM

The aim of this narrative was to describe the medical and personal life story of a young woman with Rett syndrome and to offer a history that highlights developments in the unraveling of this condition from its initial recognition to our current understanding.

CONCLUSION

We believe that much can be learned from the humanistic style of care provision combined with the best possible level of assisted autonomy and life enjoyment of the young woman with Rett syndrome. In addition, the approach to collaborative research by dedicated and often charitable leaders in the field can teach us many important lessons about the ethics of clinical and health services research.

Altered gut microbiota in Rett syndrome

BACKGROUND

The human gut microbiota directly affects human health, and its alteration can lead to gastrointestinal abnormalities and inflammation. Rett syndrome (RTT), a progressive neurological disorder mainly caused by mutations in MeCP2 gene, is commonly associated with gastrointestinal dysfunctions and constipation, suggesting a link between RTT's gastrointestinal abnormalities and the gut microbiota. The aim of this study was to evaluate the bacterial and fungal gut microbiota in a cohort of RTT subjects integrating clinical, metabolomics and metagenomics data to understand if changes in the gut microbiota of RTT subjects could be associated with gastrointestinal abnormalities and inflammatory status.

RESULTS

Our findings revealed the occurrence of an intestinal sub-inflammatory status in RTT subjects as measured by the elevated values of faecal calprotectin and erythrocyte sedimentation rate. We showed that, overall, RTT subjects harbour bacterial and fungal microbiota altered in terms of relative abundances from those of healthy controls, with a reduced microbial richness and dominated by microbial taxa belonging to Bifidobacterium, several Clostridia (among which Anaerostipes, Clostridium XIVa, Clostridium XIVb) as well as Erysipelotrichaceae, Actinomyces, Lactobacillus, Enterococcus, Eggerthella, Escherichia/Shigella and the fungal genus Candida. We further observed that alterations of the gut microbiota do not depend on the constipation status of RTT subjects and that this dysbiotic microbiota produced altered short chain fatty acids profiles.

CONCLUSIONS

We demonstrated for the first time that RTT is associated with a dysbiosis of both the bacterial and fungal component of the gut microbiota, suggesting that impairments of MeCP2 functioning favour the establishment of a microbial community adapted to the costive gastrointestinal niche of RTT subjects. The altered production of short chain fatty acids associated with this microbiota might reinforce the constipation status of RTT subjects and contribute to RTT gastrointestinal physiopathology.

Determinants of sleep disturbances in Rett syndrome: Novel findings in relation to genotype

Rett syndrome is a rare but severe neurological disorder associated with a mutation in the methyl CpG binding protein 2 (MECP2) gene. Sleep problems and epilepsy are two of many comorbidities associated with this disorder. This study investigated the prevalence and determinants of sleep problems in Rett syndrome using an international sample. Families with a child with a confirmed Rett syndrome diagnosis and a MECP2 mutation registered in the International Rett Syndrome Phenotype Database (InterRett) were invited to participate. Questionnaires were returned by 364/461 (78.9%) either in web-based or paper format. Families completed the Sleep Disturbance Scale for Children and provided information on the presence, nature, and frequency of their child's sleep problems. Multivariate multinomial regression was used to investigate the relationships between selected sleep problems, age group, and genotype and linear regression for the relationships between sleep disturbance scales and a range of covariates. Night waking was the most prevalent sleep problem affecting over 80% with nearly half (48.3%) currently waking often at night. Initiating and maintaining sleep was most disturbed for younger children and those with a p.Arg294* mutation. Severe seizure activity was associated with poor sleep after adjusting for age group, mutation type, and mobility. We were surprised to find associations between the p.Arg294* mutation and some sleep disturbances given that other aspects of its phenotype are milder. These findings highlight the complexities of aberrant MECP2 function in Rett syndrome and explain some of the variation in manifestation of sleep disturbances. © 2016 Wiley Periodicals, Inc.

Caretaker Quality of Life in Rett Syndrome: Disorder Features and Psychological Predictors

OBJECTIVE

Rett syndrome is a severe neurodevelopmental disorder affecting approximately one in 10,000 female births. The clinical features of Rett syndrome are known to impact both patients' and caretakers' quality of life in Rett syndrome. We hypothesized that more severe clinical features would negatively impact caretaker physical quality of life but would positively impact caretaker mental quality of life.

METHODS

Participants were individuals enrolled in the Rett Natural History Study with a diagnosis of classic Rett syndrome. Demographic data, clinical disease features, caretaker quality of life, and measures of family function were assessed during clinic visits. The Optum SF-36v2 Health Survey was used to assess caretaker physical and mental quality of life (higher scores indicate better quality of life). Descriptive, univariate, and multivariate analyses were used to characterize relationships between child and caretaker characteristics and caretaker quality of life.

RESULTS

Caretaker physical component scores (PCS) were higher than mental component scores (MCS): 52.8 (9.7) vs 44.5 (12.1). No differences were demonstrated between the baseline and 5-year follow-up. In univariate analyses, disease severity was associated with poorer PCS (P = 0.006) and improved MCS (P = 0.003). Feeding problems were associated with poorer PCS (P = 0.007) and poorer MCS (P = 0.018). In multivariate analyses, limitations in caretaker personal time and home conflict adversely affected PCS. Feeding problems adversely impacted MCS.

CONCLUSIONS

Caretaker quality of life in Rett syndrome is similar to that for caretakers in other chronic diseases. Disease characteristics significantly impact quality of life, and feeding difficulties may represent an important clinical target for improving both child and caretaker quality of life. The stability of quality-of-life scores between baseline and five years adds important value.

The Natural History of Scoliosis in Females With Rett Syndrome

STUDY DESIGN

Population-based longitudinal observational study.

OBJECTIVE

To describe the prevalence of scoliosis in Rett syndrome, structural characteristics and progression, taking into account the influences of age, genotype, and ambulatory status.

SUMMARY OF BACKGROUND DATA

Scoliosis is the most common orthopedic comorbidity in Rett syndrome yet very little is known about its natural history and influencing factors such as age, genotype, and ambulatory status.

METHODS

The infrastructure of the Australian Rett Syndrome Database was used to identify all cases with confirmed Rett syndrome in Australia and collect data on genotype and walking status. We identified radiological records and described the Cobb angle of each curve. Time to event analysis was used to estimate the median age of onset of scoliosis and the log-rank test to compare by mutation type. Latent class group analysis was used to identify groups for the trajectory of walking status over time and a multilevel linear model used to assess trajectories of scoliosis development by mutation type and walking status. We used a logistic regression model to estimate the probability of developing a scoliosis with a Cobb angle >60° at 16 years in relation to Cobb angle and walking status at 10 years of age.

RESULTS

The median age of scoliosis onset was 11 years with earliest onset in those with a p.Arg255 mutation or large deletion. Scoliosis was progressive for all mutation types except for those with the p.Arg306Cys mutation. Scoliosis progression was reduced when there was capacity to walk independently or with assistance. Cobb angle and walking ability at age 10 can be reliably used to identify those who will develop a very severe scoliosis by age 16.

CONCLUSION

These data on prognosis of scoliosis inform clinical decision making about the likelihood of progression to very severe scoliosis and the need for surgical management.

LEVEL OF EVIDENCE

4.

Clinical Guidelines for Management of Bone Health in Rett Syndrome Based on Expert Consensus and Available Evidence

OBJECTIVES

We developed clinical guidelines for the management of bone health in Rett syndrome through evidence review and the consensus of an expert panel of clinicians.

METHODS

An initial guidelines draft was created which included statements based upon literature review and 11 open-ended questions where literature was lacking. The international expert panel reviewed the draft online using a 2-stage Delphi process to reach consensus agreement. Items describe the clinical assessment of bone health, bone mineral density assessment and technique, and pharmacological and non-pharmacological interventions.

RESULTS

Agreement was reached on 39 statements which were formulated from 41 statements and 11 questions. When assessing bone health in Rett syndrome a comprehensive assessment of fracture history, mutation type, prescribed medication, pubertal development, mobility level, dietary intake and biochemical bone markers is recommended. A baseline densitometry assessment should be performed with accommodations made for size, with the frequency of surveillance determined according to individual risk. Lateral spine x-rays are also suggested. Increasing physical activity and initiating calcium and vitamin D supplementation when low are the first approaches to optimizing bone health in Rett syndrome. If individuals with Rett syndrome meet the ISCD criterion for osteoporosis in children, the use of bisphosphonates is recommended.

CONCLUSION

A clinically significant history of fracture in combination with low bone densitometry findings is necessary for a diagnosis of osteoporosis. These evidence and consensus-based guidelines have the potential to improve bone health in those with Rett syndrome, reduce the frequency of fractures, and stimulate further research that aims to ameliorate the impacts of this serious comorbidity.

The Changing Face of Survival in Rett Syndrome and MECP2-Related Disorders

PURPOSE

Survival in Rett syndrome remains unclear. Although early estimates were grim, more recent data suggest that survival into adulthood is typical. We aimed to define survival in Rett syndrome more clearly and identify risk factors for early death.

METHODS

Participants with clinical Rett Syndrome or methyl-CpG-binding protein 2 mutations without clinical RTT were recruited through the Rett Syndrome Natural History study from 2006 to 2015. Clinical details were collected, and survival was determined using the Kaplan-Meier estimator. Risk factors were assessed using Cox proportional hazards models.

RESULTS

Among 1189 valid participants, 51 died (range 3.9-66.6 years) during the 9-year follow-up period. Those who died included 36 (3.9%) classic Rett syndrome females, 5 (5.9%) atypical severe Rett syndrome females, 1 (2.4%) non-Rett syndrome female, the single atypical severe male, 6 (30%) non-Rett syndrome males, and 2 (7.1%) methyl-CpG-binding protein 2 duplication syndrome males. All atypical mild Rett syndrome females, methyl-CpG-binding protein 2 duplication syndrome females, and the single classic Rett syndrome male remain alive. Most deaths were due to cardiorespiratory issues. Only one died from severe malnutrition, scoliosis, and extreme frailty. Survival for classic and atypical Rett syndrome was greater than 70% at 45 years. Overall severity and several modifiable risk factors, including ambulation, weight, and seizures, were associated with mortality in classic Rett syndrome.

CONCLUSIONS

Survival into the fifth decade is typical in Rett syndrome, and death due to extreme frailty has become rare. Although the leading cause of death remains cardiorespiratory compromise, many risk factors for early death are modifiable. Intense therapeutic interventions could further improve the prognosis for individuals with Rett syndrome.

Rett Syndrome: Reaching for Clinical Trials

Rett syndrome (RTT) is a syndromic autism spectrum disorder caused by loss-of-function mutations in MECP2. The methyl CpG binding protein 2 binds methylcytosine and 5-hydroxymethycytosine at CpG sites in promoter regions of target genes, controlling their transcription by recruiting co-repressors and co-activators. Several preclinical studies in mouse models have identified rational molecular targets for drug therapies aimed at correcting the underlying neural dysfunction. These targeted therapies are increasingly translating into human clinical trials. In this review, we present an overview of RTT and describe the current state of preclinical studies in methyl CpG binding protein 2-based mouse models, as well as current clinical trials in individuals with RTT.

Longitudinal bone mineral content and density in Rett syndrome and their contributing factors

Bone mass and density are low in females with Rett syndrome. This study used Dual energy x-ray absorptiometry to measure annual changes in z-scores for areal bone mineral density (aBMD) and bone mineral content (BMC) in the lumbar spine and total body in an Australian Rett syndrome cohort at baseline and then after three to four years. Bone mineral apparent density (BMAD) was calculated in the lumbar spine. Annual changes in lean tissue mass (LTM) and bone area (BA) were also assessed. The effects of age, genotype, mobility, menstrual status and epilepsy diagnosis on these parameters were also investigated. The baseline sample included 97 individuals who were representative of the total live Australian Rett syndrome population under 30years in 2005 (n=274). Of these 74 had a follow-up scan. Less than a quarter of females were able to walk on their own at follow-up. Bone area and LTM z-scores declined over the time between the baseline and follow-up scans. Mean height-standardised z-scores for the bone outcomes were obtained from multiple regression models. The lumbar spine showed a positive mean annual BMAD z-score change (0.08) and a marginal decrease in aBMD (-0.04). The mean z-score change per annum for those 'who could walk unaided' was more positive for LS BMAD (p=0.040). Total body BMD mean annual z-score change from baseline to follow-up was negative (-0.03). However this change was positive in those who had achieved menses prior to the study (0.03, p=0,040). Total body BMC showed the most negative change (-0.60), representing a decrease in bone mineral content over time. This normalised to a z-score change of 0.21 once adjusted for the reduced lean tissue mass mean z-score change (-0.21) and bone area mean z-score change (-0.14). Overall, the bone mineral content, bone mineral density, bone area and lean tissue mass z-scores for all outcome measures declined, with the TB BMC showing significant decreases. Weight, height and muscle mass appear to have impacts on bone formation and we recommend that nutritional intake should be closely monitored and a physical activity plan developed to optimise bone health. Pubertal progression should also be assessed in conjunction with serial densitometry assessments to track bone mass and density changes over time.

Experience of gastrostomy using a quality care framework: the example of rett syndrome

Rett syndrome is one of many severe neurodevelopmental disorders with feeding difficulties. In this study, associations between feeding difficulties, age, MECP2 genotype, and utilization of gastrostomy were investigated. Weight change and family satisfaction following gastrostomy were explored. Data from the longitudinal Australian Rett Syndrome Database whose parents provided data in the 2011 family questionnaire (n=229) were interrogated. We used logistic regression to model relationships between feeding difficulties, age group, and genotype. Content analysis was used to analyze data on satisfaction following gastrostomy. In those who had never had gastrostomy and who fed orally (n=166/229), parents of girls<7 years were more concerned about food intake compared with their adult peers (odds ratio [OR] 4.26; 95% confidence interval [CI] 1.29, 14.10). Those with a p.Arg168 mutation were often perceived as eating poorly with nearly a 6-fold increased odds of choking compared to the p.Arg133Cys mutation (OR 5.88; 95% CI 1.27, 27.24). Coughing, choking, or gagging during meals was associated with increased likelihood of later gastrostomy. Sixty-six females (28.8%) had a gastrostomy, and in those, large MECP2 deletions and p.Arg168 mutations were common. Weight-for-age z-scores increased by 0.86 (95% CI 0.41, 1.31) approximately 2 years after surgery. Families were satisfied with gastrostomy and felt less anxious about the care of their child. Mutation type provided some explanation for feeding difficulties. Gastrostomy assisted the management of feeding difficulties and poor weight gain, and was acceptable to families. Our findings are likely applicable to the broader community of children with severe disability.

Pubertal development in Rett syndrome deviates from typical females

BACKGROUND

Rett syndrome is a unique neurodevelopmental disorder, affecting approximately one in 10,000 live female births, most experiencing reduced growth. We characterized pubertal trajectories in females with Rett syndrome. We hypothesized that pubertal trajectory deviates from the general female population with early pubertal onset and delayed menarche.

METHODS

Participants were individuals enrolled in the Rett Syndrome Natural History Study with clinical diagnosis of Rett syndrome or mutations in MECP2. Intervals to thelarche, adrenarche, and menarche were assessed by survival analysis; body mass index, mutation type, clinical severity, and pubertal milestone relationships were assessed by log-likelihood test; pathway synchrony (relationship between thelarche, adrenarche, and menarche) was assessed by chi-squared analysis.

RESULTS

Compared with the general female population, more than 25% initiated puberty early, yet entered menarche later (median age 13.0 years). A total of 19% experienced delayed menarche. Median length of puberty, from thelarche to menarche, was 3.9 years. Higher body mass index correlated with earlier thelarche and adrenarche but not menarche; milder mutations correlated with earlier menarche; and milder clinical presentation correlated with earlier thelarche and menarche. Fifty-two percent entered puberty in synchrony, but different from the general population, 15% led with thelarche and 32% with adrenarche.

CONCLUSIONS

Pubertal trajectories in Rett syndrome differ from general population, entering puberty early and reaching menarche later. Body mass index affects pubertal timing, but the relationship between specific mutations, clinical presentation, and underlying neuroendocrine pathology is less clear.

Prevalence, clinical investigation, and management of gallbladder disease in Rett syndrome

AIM

This study determined the prevalence of cholelithiasis and/or cholecystectomy in Rett syndrome, described gallbladder function in a clinical cohort, and identified recommendations for assessment and management of gallbladder disease.

METHOD

The incidence of cholelithiasis/cholecystectomy was estimated from data describing 270 and 681 individuals with a pathogenic MECP2 mutation in the Australian Rett Syndrome Database and the International Rett Syndrome Phenotype Database respectively. Gallbladder function in 25 females (mean age 16y 5mo, SD 20y 7mo, range 3y 5mo-47y 10mo) with Rett syndrome (RTT) was evaluated with clinical assessment and ultrasound of the gallbladder. The Delphi technique was used to develop assessment and treatment recommendations.

RESULTS

The incidence rate for cholelithiasis and/or cholecystectomy was 2.3 (95% confidence interval [CI] 1.1-4.2) and 1.8 (95% CI 1.0-3.0) per 1000 person-years in the Australian and International Databases respectively. The mean contractility index of the gallbladder for the clinical sample was 46.5% (SD 38.3%), smaller than for healthy individuals but similar to children with Down syndrome, despite no clinical symptoms. After excluding gastroesophageal reflux, gallbladder disease should be considered as a cause of abdominal pain in RTT and cholecystectomy recommended if symptomatic.

INTERPRETATION

Gallbladder disease is relatively common in RTT and should be considered in the differential diagnosis of abdominal pain in RTT.

Twenty years of surveillance in Rett syndrome: what does this tell us?

Background

The clinical characteristics of children diagnosed with Rett syndrome are well described. Survival and how these characteristics persist or change in adulthood are less well documented. This study aimed to describe overall survival and adult health in those with Rett syndrome.

Methods

Using the Kaplan-Meier method, we estimated survival of individuals registered with the Australian Rett syndrome Database (ARSD) who had been followed for up to 20 years (n = 396). We then conducted logistic and linear regression analyses investigating epilepsy, musculoskeletal, gastrointestinal, autonomic dysfunction and behaviour of individuals aged 18 years and over using cross sectional cohorts from the ARSD (n = 150) and the international database InterRett (n = 273).

Results

The likelihood of survival was 77.6% at 20 years, 71.5% at 25 years and 59.8% at 37 years. The median age of the combined cross-sectional cohort was 25 years (range 18 to 54 years), the majority (71%) were living in their parental home and the remainder being cared for in group homes or other institutions. Just over half walked either independently (18%) or with assistance (43%). The majority (86%) had scoliosis with 40% of those having undergone corrective surgery. Almost two-thirds (64%) of the women were taking anti-epileptic medications at the time of data collection. Constipation was highly prevalent (83%) and many experienced bloating (53%). Biliary dyskinesia, inflammation or infection of the gallbladder was reported for 20 women (5%) and of those 13 had undergone gallbladder surgery. Sleep disturbance was relatively common (63%), and adverse mood events and anxiety were slightly more prevalent in those aged 26-30 years in comparison to the younger and older age groups. Other frequently reported medical conditions included urinary tract infections, pneumonia and other respiratory conditions.

Conclusions

Survival in Rett syndrome has now been estimated with the most accurate follow up to date. During adulthood, continuation of multidisciplinary services and programs is necessary to optimise health and wellbeing.

Gastrointestinal dysmotility in Rett syndrome

OBJECTIVES

Through evidence review and the consensus of an expert panel, we developed recommendations for the clinical management of gastroesophageal reflux disease, constipation, and abdominal bloating in Rett syndrome.

METHODS

Based on review of the literature and family concerns expressed on RettNet, initial draft recommendations were created. Wherein the literature was lacking, 25 open-ended questions were included. Input from an international, multidisciplinary panel of clinicians was sought using a 2-stage modified Delphi process to reach consensus agreement. Items related to the clinical assessment and management of gastroesophageal reflux disease, constipation, and abdominal bloating.

RESULTS

Consensus was achieved on 78 of 85 statements. A comprehensive approach to the assessment of gastroesophageal reflux and reflux disease, constipation, and abdominal bloating was recommended, taking into account impairment of communication skills in Rett syndrome. A stepwise approach to the management was identified with initial use of conservative strategies, escalating to pharmacological measures and surgery, if necessary.

CONCLUSIONS

Gastrointestinal dysmotility occurs commonly in Rett syndrome. These evidence- and consensus-based recommendations have the potential to improve care of dysmotility issues in a rare condition and stimulate research to improve the present limited evidence base.