Gastrointestinal dysmotility in Rett syndrome

Recommendations for the management of gastrointestinal comorbidities with or without trofinetide use in rett syndrome

INTRODUCTION

Although gastrointestinal (GI) comorbidities are experienced by over 90% of individuals with Rett syndrome (RTT), a neurodevelopmental disorder associated with mutations in the MECP2 gene, many neurologists and pediatricians do not rank the management of these comorbidities among the most important treatment goals for RTT. Trofinetide, the first approved pharmacologic treatment for RTT, confers improvements in RTT symptoms but is associated with adverse GI events, primarily diarrhea and vomiting. Treatment strategies for GI comorbidities and drug-associated symptoms in RTT represent an unmet clinical need.

AREAS COVERED

This perspective covers GI comorbidities experienced by those with RTT, either with or without trofinetide treatment. PubMed literature searches were undertaken on treatment recommendations for the following conditions: constipation, diarrhea, vomiting, aspiration, dysphagia, gastroesophageal reflux, nausea, gastroparesis, gastritis, and abdominal bloating.

EXPERT OPINION

The authors recommend a proactive approach to management of symptomatic GI comorbidities and drug-associated symptoms in RTT to enhance drug tolerance and improve the quality of life of affected individuals. Management strategies for common GI comorbidities associated with RTT are reviewed based on authors' clinical experience and augmented by recommendations from the literature.

The sleep problems in individuals with Rett syndrome and their caregivers

LAY ABSTRACT

Sleep problems are common and impactful among individuals with Rett syndrome (RTT) and their caregivers. We examined the sleep patterns of 29 RTT patients and their primary caregivers using various assessment tools. The study found that a majority of the patients experienced sleep disturbances, with younger patients showing more sleep difficulties. Caregivers also reported poor sleep quality. The findings emphasize the need to address sleep problems in RTT management, as improving sleep quality can positively impact the well-being of individuals with RTT and their caregivers.

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.

Functional contribution of the intestinal microbiome in autism spectrum disorder, attention deficit hyperactivity disorder, and Rett syndrome: a systematic review of pediatric and adult studies

Introduction

Critical phases of neurodevelopment and gut microbiota diversification occur in early life and both processes are impacted by genetic and environmental factors. Recent studies have shown the presence of gut microbiota alterations in neurodevelopmental disorders. Here we performed a systematic review of alterations of the intestinal microbiota composition and function in pediatric and adult patients affected by autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), and Rett syndrome (RETT).

Methods

We searched selected keywords in the online databases of PubMed, Cochrane, and OVID (January 1980 to December 2021) with secondary review of references of eligible articles. Two reviewers independently performed critical appraisals on the included articles using the Critical Appraisal Skills Program for each study design.

Results

Our systematic review identified 18, 7, and 3 original articles describing intestinal microbiota profiles in ASD, ADHD, and RETT, respectively. Decreased Firmicutes and increased Bacteroidetes were observed in the gut microbiota of individuals affected by ASD and ADHD. Proinflammatory cytokines, short-chain fatty acids and neurotransmitter levels were altered in ASD and RETT. Constipation and visceral pain were related to changes in the gut microbiota in patients affected by ASD and RETT. Hyperactivity and impulsivity were negatively correlated with Faecalibacterium (phylum Firmicutes) and positively correlated with Bacteroides sp. (phylum Bacteroidetes) in ADHD subjects. Five studies explored microbiota-or diet-targeted interventions in ASD and ADHD. Probiotic treatments with Lactobacillus sp. and fecal microbiota transplantation from healthy donors reduced constipation and ameliorated ASD symptoms in affected children. Perinatal administration of Lactobacillus sp. prevented the onset of Asperger and ADHD symptoms in adolescence. Micronutrient supplementation improved disease symptomatology in ADHD without causing significant changes in microbiota communities' composition.

Discussion

Several discrepancies were found among the included studies, primarily due to sample size, variations in dietary practices, and a high prevalence of functional gastrointestinal symptoms. Further studies employing longitudinal study designs, larger sample sizes and multi-omics technologies are warranted to identify the functional contribution of the intestinal microbiota in developmental trajectories of the human brain and neurobehavior.

Systematic review registration

https://clinicaltrials.gov/, CRD42020158734.

MECP2-related disorders while gene-based therapies are on the horizon

The emergence of new genetic tools has led to the discovery of the genetic bases of many intellectual and developmental disabilities. This creates exciting opportunities for research and treatment development, and a few genetic disorders (e.g., spinal muscular atrophy) have recently been treated with gene-based therapies. MECP2 is found on the X chromosome and regulates the transcription of thousands of genes. Loss of MECP2 gene product leads to Rett Syndrome, a disease found primarily in females, and is characterized by developmental regression, motor dysfunction, midline hand stereotypies, autonomic nervous system dysfunction, epilepsy, scoliosis, and autistic-like behavior. Duplication of MECP2 causes MECP2 Duplication Syndrome (MDS). MDS is found mostly in males and presents with developmental delay, hypotonia, autistic features, refractory epilepsy, and recurrent respiratory infections. While these two disorders share several characteristics, their differences (e.g., affected sex, age of onset, genotype/phenotype correlations) are important to distinguish in the light of gene-based therapy because they require opposite solutions. This review explores the clinical features of both disorders and highlights these important clinical differences.

Gastrointestinal manifestations in pediatric and adult patients with Rett syndrome: an analysis of US claims and physician survey data

Aim: Patients with Rett syndrome (RTT) experience gastrointestinal (GI) manifestations. This study aimed to describe the prevalence of GI manifestations and the associated medical costs in patients with RTT in the USA. Patients & Methods: The study combined an insurance claims database analysis with a survey of 100 physicians experienced in RTT management. Results: GI manifestations affected 43.0% of 5940 patients, with increased prevalence in pediatric patients (45.6%) relative to adult patients (40.2%). Annualized mean medical cost of managing GI manifestations was $4473. Only 5.9-8.2% of neurologists and pediatricians ranked GI symptom management among the five most important treatment goals. Conclusion: Patients with RTT experience a high burden of GI manifestations, which translate to considerable medical costs. Importantly, the prevalence of GI manifestations was likely underestimated in this study, as only those symptoms which resulted in a healthcare encounter were captured.

Exploring gastrointestinal health in MECP2 duplication syndrome

BACKGROUND

MECP2 duplication syndrome (MDS) is a rare neurogenetic syndrome caused by duplications of MECP2 at the Xq28 region. Although constipation and gastrointestinal reflux are reported in MDS, a comprehensive characterization of gastrointestinal health has not been fully explored.

METHODS

We conducted a parent survey to explore the characteristics of gastrointestinal health in individuals with MDS using a secure online registry and compared differences in gastrointestinal symptoms between individuals with MDS and those with Rett syndrome (RTT).

KEY RESULTS

One hundred six surveys were analyzed. Symptoms commonly associated with constipation occurred in 72% to 89% of MDS individuals. Eleven percent of MDS individuals underwent surgery for complications associated with constipation. We observed a bimodal distribution for gastroesophageal reflux disease (GERD) and gastrostomy feeding, with higher prevalence in 0-3 and >12-year-old MDS individuals. Constipation and GERD were significantly more common, and gas bloating was significantly less common in MDS than in RTT. Biliary tract disease requiring surgery was an unrecognized problem in 5% of MDS individuals. We determined that gastrointestinal problems in MDS individuals contribute to caretaker burden.

CONCLUSION AND INFERENCES

Our study is the first in-depth investigation that characterizes gastrointestinal health in MDS and enumerates differences in gastrointestinal symptoms between MDS and RTT. Strategies to reduce gastrointestinal symptoms will alleviate caregiver burden in MDS. Further studies are needed to examine the mechanisms that cause gastrointestinal problems in MDS.

Trofinetide for the treatment of Rett syndrome: a randomized phase 3 study

Rett syndrome is a rare, genetic neurodevelopmental disorder. Trofinetide is a synthetic analog of glycine-proline-glutamate, the N-terminal tripeptide of the insulin-like growth factor 1 protein, and has demonstrated clinical benefit in phase 2 studies in Rett syndrome. In this phase 3 study ( https://clinicaltrials.gov identifier NCT04181723 ), females with Rett syndrome received twice-daily oral trofinetide (n = 93) or placebo (n = 94) for 12 weeks. For the coprimary efficacy endpoints, least squares mean (LSM) change from baseline to week 12 in the Rett Syndrome Behaviour Questionnaire for trofinetide versus placebo was -4.9 versus -1.7 (P = 0.0175; Cohen's d effect size, 0.37), and LSM Clinical Global Impression-Improvement at week 12 was 3.5 versus 3.8 (P = 0.0030; effect size, 0.47). For the key secondary efficacy endpoint, LSM change from baseline to week 12 in the Communication and Symbolic Behavior Scales Developmental Profile Infant-Toddler Checklist Social Composite score was -0.1 versus -1.1 (P = 0.0064; effect size, 0.43). Common treatment-emergent adverse events included diarrhea (80.6% for trofinetide versus 19.1% for placebo), which was mostly mild to moderate in severity. Significant improvement for trofinetide compared with placebo was observed for the coprimary efficacy endpoints, suggesting that trofinetide provides benefit in treating the core symptoms of Rett syndrome.

Pain in Rett syndrome: a pilot study and a single case study on the assessment of pain and the construction of a suitable measuring scale

Background

Rett Syndrome (RTT) is a severe, neurodevelopmental disorder mainly caused by mutations in the MECP2 gene, affecting around 1 in 10,000 female births. Severe physical, language, and social impairments impose a wide range of limitations in the quality of life of the patients with RTT. Comorbidities of patients with RTT are varied and cause a lot of pain, but communicating this suffering is difficult for these patients due to their problems, such as apraxia that does not allow them to express pain in a timely manner, and their difficulties with expressive language that also do not permit them to communicate. Two studies, a pilot study and a single case study, investigate the manifestation of pain of patients with RTT and propose a suitable scale to measure it.

Aims of this study

The first aim was to describe pain situations of RTT by collecting information by parents; the second aim was to test and compare existing questionnaires for non-communicating disorders on pain such as Pain assessment in advanced demenzia (PAINAD), the Critical care pain observation tool (CPOT) and the Non-communicating Children’s Pain Checklist-Revised (NCCPC-R) to assess which of them is best related to the pain behavior of patients with RTT. The third aim was to identify the specific verbal and non-verbal behaviors that characterize pain in girls with Rett syndrome, discriminating them from non-pain behaviors.

Method

Nineteen participants, eighteen girls with RTT and one girl with RTT with 27 manifestations of pain were video-recorded both in pain and base-line conditions. Two independent observers codified the 90 video-recording (36 and 54) to describe their behavioral characteristics.

Results

The two studies showed that the most significant pain behaviors expressed by girls with respect to the baseline condition, at the facial level were a wrinkled forehead, wide eyes, grinding, banging teeth, complaining, making sounds, crying and screaming, and the most common manifestations of the body were tremors, forward and backward movement of the torso, tension in the upper limbs, increased movement of the lower limbs and a sprawling movement affecting the whole body.

Conclusion

The results of the two studies helped to create an easy-to-apply scale that healthcare professionals can use to assess pain in patients with Rett’s syndrome. This scale used PAINAD as its basic structure, with some changes in the items related to the behavior of patients with RTT.

Exploring the characteristics and most bothersome symptoms in MECP2 duplication syndrome to pave the path toward developing parent-oriented outcome measures

BACKGROUND

MECP2 Duplication Syndrome (MDS), resulting from the duplication of Xq28 region, including MECP2, is a rare disorder with a nascent understanding in clinical features and severity. Studies using antisense oligonucleotides revealed a broad phenotypic rescue in transgenic mice. With human clinical trials on the horizon, there is a need to develop clinical outcome measures for MDS.

METHODS

We surveyed caregivers of MDS individuals to explore the frequency and severity of MDS clinical features, and identify the most meaningful symptoms/domains that need to be included in the outcome measure scales.

RESULTS

A total of 101 responses were eligible for the survey. The top six most meaningful symptoms to caregivers in descending order included epilepsy, gross motor, fine motor, communication, infection, and constipation problems. Epilepsy was present in 58.4% of the subjects and 75% were drug-resistant, Furthermore, ~12% required intensive care unit (ICU) admission. Infections were present in 55% of the subjects, and one-fourth of them required ICU admission. Constipation was present in ~85% of the subjects and one-third required enemas/suppositories.

CONCLUSION

Our study is one of the largest cohorts conducted on MDS individuals characterizing the frequency and severity of MDS symptoms. Additionally, these study results will contribute to establishing a foundation to develop parent-reported outcomes in MDS.

Enablers and barriers in dental attendance in Rett syndrome: an international observational study

AIMS

Intellectual and developmental disabilities are heterogeneous in aetiology and presentation, and one cannot make assumptions about the oral health barriers of those with Rett syndrome (RTT) based on findings from generic studies. This study investigated caregivers' perceptions regarding access to dental care for those with (RTT), and associations of dental treatments received by those with RTT with their caregivers' perceived value of oral health and perception of their own as well as their daughter's dental anxiety.

METHODS AND RESULTS

Retrospective observational data of a subset of individuals with confirmed MECP2 mutations in the InterRett database (n = 216) were used to explore caregiver-related factors and their relationships with longitudinal data on dental service utilisation, using negative binomial regression. The main reported barriers to dental care access for individuals with RTT were primarily dentist-related in nature, regardless of dental service history. Those with reported dental nonattendance were of older age. Increasing levels of caregiver-reported dental fear were associated with less frequent dental check-ups or for any appointments for affected individuals.

CONCLUSIONS

Dentist-related barriers and caregiver-reported anxiety may both adversely affect dental attendance for those with RTT. Future research should explore caregivers' beliefs and oral health literacy.

Comorbidities and quality of life in children with intellectual disability

BACKGROUND

Many children with intellectual disability live with medical comorbidities. This study examined the impacts of comorbidities on quality of life (QOL) of children with intellectual disabilities and whether impacts varied with caregiver perceptions that medical needs had been met.

METHODS

Primary caregivers of 447 children (aged 5-19 years) with an intellectual disability reported on their child's medical comorbidities and the extent to which they perceived their child's medical needs had been met in a cross-sectional observational study. The Quality of Life Inventory-Disability was used to measure QOL on a 100-point scale. Linear regression models including interaction terms were used to evaluate their associations.

RESULTS

Parent-reported recurrent child pain (-4.97, 95% CI -8.21, -1.72), night-time sleep disturbances (-4.98, 95% CI -7.23, -2.73), daytime somnolence (-8.71, 95% CI -11.30, -2.73), seizures that occurred at least weekly (-7.59, 95% CI -13.50, -1.68) and conservatively managed severe scoliosis (-7.39, 95% CI -12.97, -1.81) were negatively associated with child QOL. Despite the majority of parents (~70%) perceiving that their child's medical needs had been met to a great extent, this did not significantly moderate the association between any comorbidities and QOL.

CONCLUSIONS

Comorbidities were common and had marked associations with QOL. Evaluation and management of pain and sleep disturbance continue to be high priorities in improving QOL of young people with intellectual disabilities. Further research on the optimal methods of managing these comorbidities is warranted.

Oral health care and service utilisation in individuals with Rett syndrome: an international cross-sectional study

BACKGROUND

There is a dearth of literature available on the comparative oral health status of those with Rett syndrome (RTT) despite diurnal bruxism being a supportive diagnostic criterion for the disorder. This study was designed to investigate the dental experiences of individuals with RTT in terms of perceived at-home and professional dental care.

METHODS

Using data in the InterRett database, provided by English-speaking families of individuals with a confirmed MECP2 genetic mutation, the study investigated relationships between dental problems, oral care, child factors including bruxism and use of gastrostomy, and socioeconomic indicators. The study also explored relationships between dental presentations and socioeconomic, child, and family-related factors.

RESULTS

Individuals with RTT exhibiting bruxism were more likely to access dental treatment. Those who had full oral feeding had a higher incidence rate of dental treatment than those with full tube feeding. A conservative (under) estimation of the overall dental caries progression rate revealed that this may be similar to that of the normal population.

CONCLUSIONS

Drivers for dental treatment in RTT include bruxism as well as dental caries. Those who have full oral feeding experience more dental treatment than those with full tube feeding. A higher maternal education level may confer a protective effect for oral health outcomes in those with RTT. Nevertheless, families generally tended to value the importance of oral health despite reported difficulties in day-to-day mouth care.

Oral parafunction and bruxism in Rett syndrome and associated factors: An observational study

OBJECTIVES

To explore patterns of parafunction, and bruxism, and its relationships with genotype and snoring in individuals with Rett syndrome (RTT).

METHODS

Retrospective observational data of those with confirmed MECP2 mutations in the InterRett database (n = 216) were used to investigate experience of parafunctional habits, and bruxism and their relationships with genotype and snoring using multivariable linear regression.

RESULTS

The prevalence of parafunction was 98.2%. Bruxism was reported (66.2%) with the patterns mostly both diurnal and nocturnal (44.1%) and exclusively diurnal (42.7%). Compared to individuals with C-terminal deletion, individuals with p.Arg106Trp mutations were less likely to have bruxism reported (aOR = 0.15; 95% CI 0.02-0.98, p = 0.05) and those with p.Arg168* mutation were more likely to have frequent bruxism than none or occasional bruxism reported (aROR 3.4; 95% CI 1.1-10.7 p = 0.04). The relative odds of having nocturnal bruxism constantly, compared to none/occasionally, were higher among those 'always' snoring (aROR 6.24; 95% CI 2.1-18.2, p = 0.001) than those with no snoring.

CONCLUSIONS

There appeared to be genotypic association with bruxism in p.Arg168* and p.Arg106Trp mutations and association between nocturnal bruxism and frequent snoring in an international sample of individuals with RTT. Clinical significance of the high prevalence of bruxism should be highlighted in relation to difficulty communicating pain and increased dental treatment need in RTT.

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.

Phenotypes in adult patients with Rett syndrome: results of a 13-year experience and insights into healthcare transition

BACKGROUND

Rett syndrome is a complex genetic disorder with age-specific manifestations and over half of the patients surviving into middle age. However, little information about the phenotype of adult individuals with Rett syndrome is available, and mainly relies on questionnaires completed by caregivers. Here, we assess the clinical manifestations and management of adult patients with Rett syndrome and present our experience in transitioning from the paediatric to the adult clinic.

METHODS

We analysed the medical records and molecular data of women aged ≥18 years with a diagnosis of classic Rett syndrome and/or pathogenic variants in MECP2, CDKL5 and FOXG1, who were in charge of our clinic.

RESULTS

Of the 50 women with classic Rett syndrome, 94% had epilepsy (26% drug-resistant), 20% showed extrapyramidal signs, 40% sleep problems and 36% behavioural disorders. Eighty-six % patients exhibited gastrointestinal problems; 70% had scoliosis and 90% low bone density. Breathing irregularities were diagnosed in 60%. None of the patients had cardiac issues. CDKL5 patients experienced fewer breathing abnormalities than women with classic Rett syndrome.

CONCLUSION

The delineation of an adult phenotype in Rett syndrome demonstrates the importance of a transitional programme and the need of a dedicated multidisciplinary team to optimise the clinical management of these patients.

Alternating Hemiplegia of Childhood: gastrointestinal manifestations and correlation with neurological impairments

Background

Alternating Hemiplegia of Childhood (AHC) is caused by mutations of the ATP1A3 gene which is expressed in brain areas that include structures controling autonomic, gastrointestinal, gut motility and GABAergic functions. We aimed to investigate, in a cohort of 44 consecutive AHC patients, two hypotheses: 1) AHC patients frequently manifest gastrointestinal, particularly motility, problems. 2) These problems are often severe and their severity correlates with neurological impairments.

Results

41/44 (93%) exhibited gastrointestinal symptoms requiring medical attention. For these 41 patients, symptoms included constipation (66%), swallowing problems (63%), vomiting (63%), anorexia (46%), diarrhea (44%), nausea (37%), and abdominal pain (22%). Symptoms indicative of dysmotility occurred in 33 (80%). The most common diagnoses were oropharyngeal dysphagia (63%) and gastroesophageal reflux (63%). 16 (39%) required gastrostomy and two fundoplication. Severity of gastrointestinal symptoms correlated with non-paroxysmal neurological disability index, Gross Motor Function Classification System scores, and with the presence/absence of non-gastrointestinal autonomic dysfunction (p = 0.031, 0.043, Spearman correlations and 0.0166 Cramer’s V, respectively) but not with the paroxysmal disability index (p = 0.408).

Conclusions

Most AHC patients have gastrointestinal problems. These are usually severe, most commonly are indicative of dysmotility, often require surgical therapies, and their severity correlates with that of non-paroxysmal CNS manifestations. Our findings should help in management-anticipatory guidance of AHC patients. Furthermore, they are consistent with current understandings of the pathophysiology of AHC and of gastrointestinal dysmotility, both of which involve autonomic and GABAergic dysfunction.

Rehabilitation interventions in Rett syndrome: a scoping review

AIM

To summarize existing interventions and their outcomes in Rett syndrome (RTT) rehabilitation and identify gaps in the literature.

METHOD

Five databases (Ovid MEDLINE, Ovid Embase Classic, Ovid PsycINFO, EBSCO CINAHL Plus, and ProQuest ERIC) were systematically searched up to 23rd July 2018 for studies describing rehabilitation interventions. Data on study participants, design, and outcomes were extracted.

RESULTS

Sixty-two articles were included in the final review. Evidence consistently demonstrated that females with RTT can improve their gross motor, fine motor, and communicative skills with rehabilitation. All 11 interventions targeting gross motor function, namely ambulation, achieved functional improvements. Twenty of 24 articles describing fine motor rehabilitation studies succeeded in decreasing stereotypies, improving functional hand use, and/or reducing self-injurious behaviors. Twenty-one of 22 studies describing communication interventions succeeded in training choice-making, communicative language, or socialization behavior. Other key findings include the positive interplay between physical and communicative rehabilitation outcomes, and the ability of females with RTT to improve their cognitive abilities during intervention.

INTERPRETATION

Rehabilitation can impact the daily lives of females with RTT and their caregivers in clinically meaningful ways.

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.

Rett Syndrome and Other Neurodevelopmental Disorders Share Common Changes in Gut Microbial Community: A Descriptive Review

In this narrative review, we summarize recent pieces of evidence of the role of microbiota alterations in Rett syndrome (RTT). Neurological problems are prominent features of the syndrome, but the pathogenic mechanisms modulating its severity are still poorly understood. Gut microbiota was recently demonstrated to be altered both in animal models and humans with different neurodevelopmental disorders and/or epilepsy. By investigating gut microbiota in RTT cohorts, a less rich microbial community was identified which was associated with alterations of fecal microbial short-chain fatty acids. These changes were positively correlated with severe clinical outcomes. Indeed, microbial metabolites can play a crucial role both locally and systemically, having dynamic effects on host metabolism and gene expression in many organs. Similar alterations were found in patients with autism and down syndrome as well, suggesting a potential common pathway of gut microbiota involvement in neurodevelopmental disorders.

Correlation Between Dysphagia and Malocclusion in Rett Syndrome: A preliminary study

Objectives

Rett syndrome (RS) is a severe neurological developmental disorder characterised by stereotypical hand movements, epileptic seizures, craniofacial dysmorphism and digestive dysfunction. This study aimed to examine the correlation between the severity of malocclusion and dysphagia in patients with RS.

Methods

This preliminary study was conducted at the Ear, Nose & Throat Clinic of the University Hospital of Siena, Siena, Italy, from January 2014 to December 2017. A total of 56 patients with RS were examined and grouped according to the severity of dysphagia (absent, mild, moderate or severe) and malocclusion (<2 mm, 2-3 mm, 3-4 mm or >4 mm).

Results

All of the patients were female and the mean age was 11.3 years. Eight (14.3%) patients had mild, 18 (32.1%) had moderate and 30 (53.6%) had severe dysphagia. Four (7.1%) patients had <2 mm occlusion, 10 (17.9%) had 2-3 mm occlusion, 26 (46.4%) had 3-4 mm occlusion and 16 (28.6%) had >4 mm occlusion. Mild dysphagia was observed in 100% and 40% of patients with <2 and 2-3 mm malocclusion, respectively, while moderate dysphagia was present in 60% and 38.5% of patients with 2-3 and 3-4 mm malocclusion, respectively. Severe dysphagia was observed in 28.6% and 87.5% of patients with 3-4 and >4 mm malocclusion, respectively. There was a significant correlation between dysphagia and malocclusion severity (P <0.001).

Conclusion

A higher degree of malocclusion was associated with more severe dysphagia among a cohort of patients with RS.

The effectiveness of music therapy for individuals with Rett syndrome and their families

BACKGROUND

Patients with Rett syndrome (RTT) present characteristic regression in communication and hand skills, which eventually leads to intellectual and physical disability. Moreover, caregivers of patients with RTT face stressors related to patients' medical and developmental concerns. Given the indications from case reports, this pilot study investigated the effectiveness of music therapy on RTT patients, as well as on parental stress for families of children with RTT.

METHODS

Families in the study group were enrolled in a twice-weekly 120-minute music therapy program for 24 weeks (n = 11), whereas families in the control group did not receive music therapy (n = 12). Participants were administered the Vineland Adaptive Behavior Scales, Rett Syndrome Clinical Severity Scale, Rett Syndrome Motor Behavioral Assessment, and Parenting Stress Index for caregivers of RTT children before and after the music therapy program.

RESULTS

Music therapy improved receptive language, verbal and non-verbal communication skills, and social interaction for RTT patients. In addition, purposeful hand function, breathing patterns, and eye contact were significantly improved. Of note, music therapy also decreased the frequency of epileptic seizures. Lastly, caregivers in the study group exhibited significantly lower stress following the program.

CONCLUSION

The 24-week music therapy program was effective in improving social interaction, communication skills, eye contact, hand function, and reducing seizure frequency among RTT patients. Additionally, music therapy was effective in relieving parenting stress, which may help healthcare providers initiate early intervention strategies that can prevent parenting stress and reduce the risk of depression.

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.

Motor, Somatosensory, Viscerosensory and Metabolic Impairments in a Heterozygous Female Rat Model of Rett Syndrome

Rett Syndrome (RTT), an autism-related disorder caused by mutation of the X-linked Methyl CpG-binding Protein 2 (MECP2) gene, is characterized by severe cognitive and intellectual deficits. While cognitive deficits are well-documented in humans and rodent models, impairments of sensory, motor and metabolic functions also occur but remain poorly understood. To better understand non-cognitive deficits in RTT, we studied female rats heterozygous for Mecp2 mutation (Mecp2^−/x); unlike commonly used male Mecp2^−/y rodent models, this more closely approximates human RTT where males rarely survive. Mecp2^−/x rats showed rapid, progressive decline of motor coordination through six months of age as assessed by rotarod performance, accompanied by deficits in gait and posture. Mecp2^−/x rats were hyper-responsive to noxious pressure and cold, but showed visceral hyposensitivity when tested by colorectal distension. Mecp2^−/x rats ate less, drank more, and had more body fat resulting in increased weight gain. Our findings reveal an array of progressive non-cognitive deficits in this rat model that are likely to contribute to the compromised quality of life that characterizes RTT.

Mecp2 regulates tnfa during zebrafish embryonic development and acute inflammation

Mutations in MECP2 cause Rett syndrome, a severe neurological disorder with autism-like features. Duplication of MECP2 also causes severe neuropathology. Both diseases display immunological abnormalities that suggest a role for MECP2 in controlling immune and inflammatory responses. Here, we used mecp2-null zebrafish to study the potential function of Mecp2 as an immunological regulator. Mecp2 deficiency resulted in an increase in neutrophil infiltration and upregulated expression of the pro- and anti-inflammatory cytokines Il1b and Il10 as a secondary response to disturbances in tissue homeostasis. By contrast, expression of the proinflammatory cytokine tumor necrosis factor alpha (Tnfa) was consistently downregulated in mecp2-null animals during development, representing the earliest developmental phenotype described for MECP2 deficiency to date. Expression of tnfa was unresponsive to inflammatory stimulation, and was partially restored by re-expression of functional mecp2 Thus, Mecp2 is required for tnfa expression during zebrafish development and inflammation. Finally, RNA sequencing of mecp2-null embryos revealed dysregulated processes predictive for Rett syndrome phenotypes.

Constipation management in people with intellectual disability: A systematic review

BACKGROUND

Constipation can lead to serious health issues and death. This systematic review summarizes international research pertaining to the management of constipation in people with intellectual disability.

METHOD

Studies published from 1990 to 2017 were identified using Medline, Cinahl, PsycINFO, Web of Science, email requests and cross-citations. Studies were reviewed narratively in relation to identified themes.

RESULTS

Eighteen studies were reviewed in relation to three themes: laxative receipt; interventions (dietary fibre, abdominal massage and macrogol); and staff issues (knowledge and training). Laxative polypharmacy was common. Studies report positive results for dietary fibre and abdominal massage although study quality was limited.

CONCLUSION

The main management response to constipation in people with intellectual disability is laxative use despite limited effectiveness. An improved evidence base is required to support the suggestion that an individualized, integrated bowel management programme may reduce constipation and associated health conditions in people with intellectual disability.

Pathogenesis of Lethal Aspiration Pneumonia in Mecp2-null Mouse Model for Rett Syndrome

Rett syndrome (RTT) is a neurodevelopmental disorder mainly caused by mutations in the gene encoding the transcriptional regulator Methyl-CpG-binding protein 2 (MeCP2), located on the X chromosome. Many RTT patients have breathing abnormalities, such as apnea and breathing irregularity, and respiratory infection is the most common cause of death in these individuals. Previous studies showed that MeCP2 is highly expressed in the lung, but its role in pulmonary function remains unknown. In this study, we found that MeCP2 deficiency affects pulmonary gene expression and structures. We also found that Mecp2-null mice, which also have breathing problems, often exhibit inflammatory lung injury. These injuries occurred in specific sites in the lung lobes. In addition, polarizable foreign materials were identified in the injured lungs of Mecp2-null mice. These results indicated that aspiration might be a cause of inflammatory lung injury in Mecp2-null mice. On the other hand, MeCP2 deficiency affected the expression of several neuromodulator genes in the lower brainstem. Among them, neuropeptide substance P (SP) immunostaining was reduced in Mecp2-null brainstem. These findings suggest that alteration of SP expression in brainstem may be involved in autonomic dysregulation, and may be one of the causes of aspiration in Mecp2-null mice.

Autonomic breathing abnormalities in Rett syndrome: caregiver perspectives in an international database study

BACKGROUND

Rett syndrome is a severe neurodevelopmental disorder associated with mutations in the MECP2 gene. Irregular breathing patterns and abdominal bloating are prominent but poorly understood features. Our aims were to characterize the abnormal breathing patterns and abdominal bloating, investigate the distribution of these by age and mutation type and examine their impact and management from a caregiver perspective.

METHODS

We invited previously recruited families from the International Rett Syndrome Study to complete a web-based questionnaire concerning their family member with Rett syndrome aged between 2 and 57 years. We used logistic regression to investigate presence, frequency and impact of breath-holding, hyperventilation, or abdominal bloating by age group and mutation type. Age of onset for both breathing abnormalities was investigated using time-to-onset analysis, and the Kaplan-Meier method was used to estimate the failure function for the study sample. Descriptive statistics were used to characterize the management of irregular breathing.

RESULTS

Questionnaires were returned by 413/482 (85.7%) families. Breath-holding was reported for 68.8%, hyperventilation for 46.4% and abdominal bloating for 42.4%. Hyperventilation was more prevalent and frequent in those younger than 7 years of age and abdominal bloating in those aged over 20 years. Onset of breathing irregularities usually occurred during early childhood. Caregivers perceived that daily life was considerably impacted for almost half (44.1%) of those with abdominal bloating and in just over than a third of those with breath-holding (35.8%) or hyperventilation (35.1%). Although perceived impact was broadly comparable between age and mutation groups for breath-holding, hyperventilation and abdominal bloating, girls and women with a p.Arg294* mutation were considered to be more affected by all three conditions. Only 31 individuals had received medically prescribed treatments including 12 different medications, added oxygen, rebreathing apparatus or non-invasive ventilation.

CONCLUSIONS

Autonomic disturbances are prevalent and burdensome in Rett syndrome. This information may guide the design of inclusion criteria and outcome measures for clinical intervention trials targeting autonomic abnormalities. Further investigation of available treatments is necessary to delineate evidence-based management pathways.

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.

Methyl-CpG binding-protein 2 function in cholinergic neurons mediates cardiac arrhythmogenesis

Sudden unexpected death occurs in one quarter of deaths in Rett Syndrome (RTT), a neurodevelopmental disorder caused by mutations in Methyl-CpG-binding protein 2 (MECP2). People with RTT show a variety of autonomic nervous system (ANS) abnormalities and mouse models show similar problems including QTc interval prolongation and hypothermia. To explore the role of cardiac problems in sudden death in RTT, we characterized cardiac rhythm in mice lacking Mecp2 function. Male and female mutant mice exhibited spontaneous cardiac rhythm abnormalities including bradycardic events, sinus pauses, atrioventricular block, premature ventricular contractions, non-sustained ventricular arrhythmias, and increased heart rate variability. Death was associated with spontaneous cardiac arrhythmias and complete conduction block. Atropine treatment reduced cardiac arrhythmias in mutant mice, implicating overactive parasympathetic tone. To explore the role of MeCP2 within the parasympathetic neurons, we selectively removed MeCP2 function from cholinergic neurons (MeCP2 ChAT KO), which recapitulated the cardiac rhythm abnormalities, hypothermia, and early death seen in RTT male mice. Conversely, restoring MeCP2 only in cholinergic neurons rescued these phenotypes. Thus, MeCP2 in cholinergic neurons is necessary and sufficient for autonomic cardiac control, thermoregulation, and survival, and targeting the overactive parasympathetic system may be a useful therapeutic strategy to prevent sudden unexpected death in RTT.

Neurogenetics in Child Neurology: Redefining a Discipline in the Twenty-first Century

Increasing knowledge on genetic etiology of pediatric neurologic disorders is affecting the practice of the specialty. I reviewed here the history of pediatric neurologic disorder classification and the role of genetics in the process. I also discussed the concept of clinical neurogenetics, with its role in clinical practice, education, and research. Finally, I propose a flexible model for clinical neurogenetics in child neurology in the twenty-first century. In combination with disorder-specific clinical programs, clinical neurogenetics can become a home for complex clinical issues, repository of genetic diagnostic advances, educational resource, and research engine in child neurology.

Rett syndrome: a wide clinical and autonomic picture

Background

Rett Syndrome is a neurodevelopmental disorder almost exclusively affecting females, characterized by a broad clinical spectrum of signs and symptoms and a peculiar course. The disease affects different body systems: nervous, muscolo-skeletal, gastro-enteric. Moreover, part of the symptoms are related to the involvement of the autonomic nervous system.

In the Tuscany Rett Center at Versilia Hospital, we collected data from 151 subjects with a clinical diagnosis of classical or variant RTT syndrome. For each subject, we assessed the severity of the condition with clinical-rating scales (ISS, PBZ), we quantified the performance of the autonomic nervous system, and we performed genetic analysis. We used multivariate statistical analysis of the data to evaluate the relation between the different clinical RTT forms, the cardiorespiratory phenotype, the different genetic mutations and the severity of the clinical picture. Individuals were classified according to existing forms: Classical RTT and three atypical RTT: Z-RTT, Hanefeld, Congenital. A correlation between C-Terminal deletions and lower severity of the clinical manifestations was evident, in the previous literature, but, considering the analysis of autonomic behaviour, the original classification can be enriched with a more accurate subdivision of Rett subgroups, which may be useful for early diagnosis.

Results

Present data emphasize some differences, not entirely described in the literature, among RTT variants. In our cohort the Z-RTT variant cases show clinical features (communication, growth, epilepsy and development), well documented by specific ISS items, less severe, if compared to classical RTT and show autonomic disorders, previously not reported in the literature. In this form epilepsy is rarely present. In contrast, Hanefeld variant shows the constant presence of epilepsy which has an earlier onset In Hanefeld variant the frequency of apneas was rare and, among the cardiorespiratory phenotypes, the feeble type is lacking.

Conclusion

A quantitative analysis of the different autonomic components reveals differences across typical and atypical forms of RTT that leads to a more accurate classification of the groups. In our cohort of RTT individuals, the inclusion of autonomic parameter in the classification leads to an improved diagnosis at earlier stages of development.

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.

Prevalence and onset of comorbidities in the CDKL5 disorder differ from Rett syndrome

Background

Initially described as an early onset seizure variant of Rett syndrome, the CDKL5 disorder is now considered as an independent entity. However, little is currently known about the full spectrum of comorbidities that affect these patients and available literature is limited to small case series. This study aimed to use a large international sample to examine the prevalence in this disorder of comorbidities of epilepsy, gastrointestinal problems including feeding difficulties, sleep and respiratory problems and scoliosis and their relationships with age and genotype. Prevalence and onset were also compared with those occurring in Rett syndrome.

Methods

Data for the CDKL5 disorder and Rett syndrome were sourced from the International CDKL5 Disorder Database (ICDD), InterRett and the Australian Rett syndrome Database (ARSD). Logistic regression (multivariate and univariate) was used to analyse the relationships between age group, mutation type and the prevalence of various comorbidities. Binary longitudinal data from the ARSD and the equivalent cross-sectional data from ICDD were examined using generalized linear models with generalized estimating equations. The Kaplan-Meier method was used to estimate the failure function for the two disorders and the log-rank test was used to compare the two functions.

Results

The likelihood of experiencing epilepsy, GI problems, respiratory problems, and scoliosis in the CDKL5 disorder increased with age and males were more vulnerable to respiratory and sleep problems than females. We did not identify any statistically significant relationships between mutation group and prevalence of comorbidities. Epilepsy, GI problems and sleep abnormalities were more common in the CDKL5 disorder than in Rett syndrome whilst scoliosis and respiratory problems were less prevalent.

Conclusion

This study captured a much clearer picture of the CDKL5 disorder than previously possible using the largest sample available to date. There were differences in the presentation of clinical features occurring in the CDKL5 disorder and in Rett syndrome, reinforcing the concept that CDKL5 is an independent disorder with its own distinctive characteristics.

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.

Altered erythrocyte membrane fatty acid profile in typical Rett syndrome: effects of omega-3 polyunsaturated fatty acid supplementation

This study mainly aims at examining the erythrocyte membrane fatty acid (FAs) profile in Rett syndrome (RTT), a genetically determined neurodevelopmental disease. Early reports suggest a beneficial effects of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) on disease severity in RTT. A total of 24 RTT patients were assigned to ω-3 PUFAs-containing fish oil for 12 months in a randomized controlled study (average DHA and EPA doses of 72.9, and 117.1mg/kgb.w./day, respectively). A distinctly altered FAs profile was detectable in RTT, with deficient ω-6 PUFAs, increased saturated FAs and reduced trans 20:4 FAs. FAs changes were found to be related to redox imbalance, subclinical inflammation, and decreased bone density. Supplementation with ω-3 PUFAs led to improved ω-6/ω-3 ratio and serum plasma lipid profile, decreased PUFAs peroxidation end-products, normalization of biochemical markers of inflammation, and reduction of bone hypodensity as compared to the untreated RTT group. Our data indicate that a significant FAs abnormality is detectable in the RTT erythrocyte membranes and is partially rescued by ω-3 PUFAs.