Deep sedation with propofol in patients with Rett syndrome

Gastrointestinal Dysfunction in Genetically Defined Neurodevelopmental Disorders

Gastrointestinal symptoms are common in most forms of neurodevelopment disorders (NDDs) such as in autism spectrum disorders (ASD). The current patient-reported outcome measures with validated questionnaires used in the general population of children without NDDS cannot be used in the autistic individuals. We explore here the multifactorial pathophysiology of ASD and the role of genetics and the environment in this disease spectrum and focus instead on possible diagnostics that could provide future objective insight into the connection of the gut-brain-microbiome in this disease entity. We provide our own data from both humans and a zebrafish model of ASD called Phelan-McDermid Syndrome. We hope that this review highlights the gaps in our current knowledge on many of these profound NDDs and that it provides a future framework upon which clinicians and researchers can build and network with other interested multidisciplinary specialties.

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.

Use of sugammadex in Rett syndrome: A case report

Rett syndrome (RS) is a neurodevelopmental disorder characterized by loss of cognitive, motor, and social skills, epilepsy, autistic behavior, abnormal airway patterns, gastroesophageal reflux, nutritional problems, and severe scoliosis. Although girls with RS show normal or near-normal growth until 6–8 months, they lose their skills after that. The anesthetic management of these patients requires care because of all these clinical features. Especially in the postoperative period, prolonged apnea is common and extubation is delayed. In this case report, the effect of using sugammadex was presented in a 16-year-old girl with RS. The patient's all bimaxillary teeth and 4 wisdom teeth were extracted under general anesthesia in one session with minimal surgical trauma and moderate bleeding. Sugammadex can be a rapid and reliable agent for the reversal of the neuromuscular block in neurodegenerative patients.

A codon-optimized Mecp2 transgene corrects breathing deficits and improves survival in a mouse model of Rett syndrome

Rett syndrome (RTT) is a severe X-linked neurodevelopmental disorder that is primarily caused by mutations in the methyl CpG binding protein 2 gene (MECP2). RTT is the second most prevalent cause of intellectual disability in girls and there is currently no cure for the disease. The finding that the deficits caused by the loss of Mecp2 are reversible in the mouse has bolstered interest in gene therapy as a cure for RTT. In order to assess the feasibility of gene therapy in a RTT mouse model, and in keeping with translational goals, we investigated the efficacy of a self-complementary AAV9 vector expressing a codon-optimized version of Mecp2 (AAV9-MCO) delivered via a systemic approach in early symptomatic Mecp2-deficient (KO) mice. Our results show that AAV9-MCO administered at a dose of 2×10¹¹ viral genome (vg)/mouse was able to significantly increase survival and weight gain, and delay the occurrence of behavioral deficits. Apneas, which are one of the core RTT breathing deficits, were significantly decreased to WT levels in Mecp2 KO mice after AAV9-MCO administration. Semi-quantitative analysis showed that AAV9-MCO administration in Mecp2 KO mice resulted in 10 to 20% Mecp2 immunopositive cells compared to WT animals, with the highest Mecp2 expression found in midbrain regions known to regulate cardio-respiratory functions. In addition, we also found a cell autonomous increase in tyrosine hydroxylase levels in the A1C1 and A2C2 catecholaminergic Mecp2+ neurons in treated Mecp2 KO mice, which may partly explain the beneficial effect of AAV9-MCO administration on apneas occurrence.

Family satisfaction following spinal fusion in Rett syndrome

PURPOSE

We evaluated family satisfaction following spinal fusion in girls with Rett syndrome.

METHODS

Families participating in the population-based and longitudinal Australian Rett Syndrome Database whose daughter had undergone spinal fusion provided data on satisfaction overall, care processes and expected changes in health and function. Content analysis of responses to open-ended questions was conducted.

RESULTS

Families reported high levels of overall satisfaction and consistently high ratings in relation to surgical and ICU care. Outstanding clinical care and the development of strong partnerships with clinical staff were much appreciated by families, whereas poor information exchange and inconsistent care caused concerns.

CONCLUSIONS

Family satisfaction is an important outcome within a patient-centred quality of care framework. Our findings suggest strategies to inform the delivery of care in relation to spinal fusion for Rett syndrome and could also inform the hospital care of other children with disability and a high risk of hospitalization.

Surgical fusion of early onset severe scoliosis increases survival in Rett syndrome: a cohort study

AIM

Scoliosis is a common comorbidity in Rett syndrome and spinal fusion may be recommended if severe. We investigated the impact of spinal fusion on survival and risk of severe lower respiratory tract infection in Rett syndrome.

METHOD

Data were ascertained from hospital medical records, the Australian Rett Syndrome Database, a longitudinal and population-based registry, and from the Australian Institute of Health and Welfare National Death Index database. Cox regression and generalized estimating equation models were used to estimate the effects of spinal surgery on survival and severe respiratory infection respectively in 140 females who developed severe scoliosis (Cobb angle ≥45°) before adulthood.

RESULTS

After adjusting for mutation type and age of scoliosis onset, the rate of death was lower in the surgery group (hazard ratio [HR] 0.30, 95% confidence interval [CI] 0.12-0.74; p=0.009) compared to those without surgery. Rate of death was particularly reduced for those with early onset scoliosis (HR 0.17, 95% CI 0.06-0.52; p=0.002). There was some evidence to suggest that spinal fusion was associated with a reduction in risk of severe respiratory infection among those with early onset scoliosis (risk ratio 0.41, 95% CI 0.16-1.03; p=0.06).

INTERPRETATION

With appropriate cautions, spinal fusion confers an advantage to life expectancy in Rett syndrome.

Perioperative management and outcome of patients with Rett syndrome undergoing scoliosis surgery: a retrospective review

BACKGROUND

Rett syndrome is a rare genetically inherited neuromuscular disorder exclusively affecting female patients. Progressive scoliosis is one of the main features of the disease and affected individuals are very likely to need spine correction surgery.

METHODS

We undertook a retrospective notes review of patients with Rett syndrome who had undergone spine surgery from 2005 to 2013. Patients were identified through the hospital's electronic records. The aim of the present study was to identify the anesthetic implications encountered and the perioperative adverse events, in an effort to improve perioperative management and reduce complications.

RESULT

We identified twenty-four children who had 29 procedures in total in this period. Frequent chest infections and poorly controlled epilepsy were the main preoperative findings. There were no adverse events during induction and intubation. Common anesthetic/analgesic drugs were used throughout. Postoperatively, gastrointestinal and respiratory tract complications were the most common. Mean intensive care unit stay was 8.1 days and mean time to discharge from hospital was 26.5 days. We had one in-hospital death.

CONCLUSIONS

Our case series demonstrates a high incidence of complications in this subpopulation, mainly postoperative. Extreme postoperative vigilance is required and recovery in a high dependency unit is highly recommended.

[Rett syndrome: double epidural catheter for the control of postoperative pain after scoliosis surgery. A literature review]

Rett syndrome is a severe and incapacitating neurological disease caused by a structural defect in the short arm of the X chromosome (Xq28). It affects females and consists of multiple and progressive neurological impairments that start from a young age, leading to lifelong disability and dependency. Scoliosis appears in more than 50% of patients and requires surgical correction in cases where the curvature is severe. Pre-anaesthetic assessment is essential in order to identify the risk factors and thus reduce the morbidity and mortality associated with the surgical procedure. We present the case of a patient affected by this syndrome and scoliosis, who was scheduled to have an instrumented thoracolumbar spine arthrodesis with general anaesthesia, which passed without incident. We evaluate the specific details of this syndrome, its potential complications, and its management from an anaesthetic point of view, emphasising the control of postoperative pain using a double epidural catheter with an infusion of local anaesthetics and fentanyl.

Anesthetic management of an adult patient with Rett syndrome and limited mouth opening -A case report-

Rett syndrome is a neurological disease that occurs only in females and it manifests with mental retardation, seizures, movement disorders, autistic behavior and abnormal breathing. A 19-year-old female with Rett syndrome underwent ophthalmologic surgery under general anesthesia at our institution. Airway control was difficult due to her limited mouth opening. We recommend that anesthesiologists should have proper knowledge about this disease and the patients to avoid the complications and problems that can be encountered during the perioperative period.

Linking MECP2 and pain sensitivity: the example of Rett syndrome

Recent animal studies suggest links between MeCP2 function and sensitivity to pain. This study investigated the nature and prevalence of atypical pain responses in Rett syndrome and their relationships with specific MECP2 mutations. Families enrolled in the Australian Rett Syndrome Database (ARSD) and InterRett database participated in this study. Cases with a known MECP2 pathogenic mutation, whose families had completed a questionnaire on registration and had answered questions on pain sensitivity were included (n = 646). Logistic regression was used to analyze relationships between the atypical pain responses and genotype. Descriptions of decreased pain sensitivity were content analyzed. The prevalence estimate of reporting an abnormal pain response was 75.2% and a decreased sensitivity to pain was 65.0% in the population-based ARSD. Families of ARSD and InterRett subjects with a C-terminal (OR 2.6; 95% CI 0.8-8.0), p.R168X (OR 2.1; 95% CI 0.7-6.1), or p.R306C (OR 2.7; 95% CI 0.8-9.6) mutation were more likely to report decreased sensitivity to pain. Parents and carers described decreased and delayed responses in situations judged likely to cause pain such as injections, falls, trauma, and burns. This study has provided the first precise estimate of the prevalence of abnormal sensitivity to pain in Rett syndrome but specific relationships with genotype are not yet clear. Clinical practice should include a low threshold for the clinical assessment of potential injuries in Rett syndrome.

Guidelines for management of scoliosis in Rett syndrome patients based on expert consensus and clinical evidence

STUDY DESIGN

Modified Delphi technique.

OBJECTIVE

To develop guidelines for the clinical management of scoliosis in Rett syndrome through evidence review and consensus expert panel opinion.

SUMMARY OF BACKGROUND DATA

Rett syndrome is a rare disorder and clinical expertise is thus with small case series. Scoliosis is a frequent association and the evidence base dealing with scoliosis management in this syndrome is limited. Parents of affected girls and women have expressed needs for more information about scoliosis and Rett syndrome.

METHODS

An initial draft of scoliosis guidelines was created based on literature review and open-ended questions where the literature was lacking. Perspectives of four parents of Rett syndrome patients informed this initial draft. Access to an online and a Microsoft Word formatted version of the draft were then sent to an international, multidisciplinary panel of clinicians via e-mail with input sought using a 2-stage modified Delphi process to reach consensus agreement. Items included clinical monitoring and intervention before the diagnosis of scoliosis; monitoring after the diagnosis of scoliosis; imaging; therapy and conservative management; bracing; and preoperative, surgical, and postoperative considerations.

RESULTS

The first draft contained 71 statements, 65 questions. The second draft comprised 88 items with agreement to strong agreement achieved on 85, to form the final guideline document. A comprehensive, life-span approach to the management of scoliosis in Rett syndrome is recommended that takes into account factors such as physical activity, posture, nutritional and bone health needs. Surgery should be considered when the Cobb angle is approximately 40 degrees to 50 degrees and must be supported by specialist management of anesthesia, pain control, seizures, and early mobilization.

CONCLUSION

Evidence- and consensus-based guidelines were successfully created and have the potential to improve care of a complex comorbidity in a rare condition and stimulate research to improve the current limited evidence base.

Over-inhibition: a model for developmental intellectual disability

Developmental intellectual disability (DID) is a daunting societal problem. Although tremendous progress has been made in defining the genetic causes of DID, therapeutic strategies remain limited. In particular, there is a marked absence of a unified approach to treating cognitive impairments associated with DID. Here, we suggest that the brain in many DID-related disorders is subject to a basic imbalance in neuronal activity, with an increased contribution of inhibition to neural circuits. This over-inhibition, in turn, is predicted to lead to deficits in synaptic plasticity and learning and memory. We further discuss possibilities for pharmacological intervention in DID, focusing on the concept of drug-induced 'therapeutic neuroadaptation' as a means of stably enhancing constitutive circuit excitability and cognition over time.

The overlapping spectrum of rett and angelman syndromes: a clinical review

Rett and Angelman syndromes comprise part of the spectrum of neurologic disorders associated with autism. Their clinical presentations overlap, with both presenting in later infancy with global developmental delays, severe speech and communication impairments, progressive microcephaly, seizures, autistic behaviors, and characteristic albeit different movement disorders and stereotypic hand movements. Although other features can help differentiate these disorders, significant phenotypic overlap and variation in severity sometimes cloud the underlying diagnosis. Rett syndrome is caused by a mutation in the MECP2 gene located on Xq28, whereas Angelman syndrome results from the loss of UBE3A function on chromosomal region 15q11-q13 related to a variety of molecular genetic mechanisms. Recent advances have uncovered interactions between these and other genes that affect the function and structure of neurons in the brain. The reversal of symptoms of Rett syndrome in a mature mouse model suggests the possibility for treatment of these and perhaps other autism-related disorders in the future.