Genetically determined encephalopathy

Minimally Invasive Bipolar Technique for Scoliosis in Rett Syndrome-Results and Complications in a Series of 22 Cases

Background: This is a retrospective study. The aim of this study is to report the results of bipolar minimally invasive fusionless surgery for scoliosis in Rett syndrome with a minimum follow-up of 2 years. Conservative treatment is often not effective in Rett syndrome scoliosis. Posterior spinal fusion (PSF) has a high rate of complications; early surgery using traditional growing rods (TGRs) controls the deformity while preserving spinal and thoracic growth before arthrodesis. The need for surgical rod lengthening still has a high rate of complications and costs. Methods: We recorded the clinical and radiological outcomes of 22 consecutive patients with Rett scoliosis who underwent bipolar fusionless surgery with a mean follow-up of 56 months (24-99). We performed a bilateral construct with rods (with or without a self-sliding device) anchored proximally with four hook claws distally to the pelvis by ilio-sacral (IS) screws through a minimally invasive approach. Results: The Cobb angle was reduced from 74.4° initially to 28.9° postoperatively and to 25.7° at the last follow-up, which corresponds to a 65% correction of the initial deformity. The gain was maintained at the last follow-up. None of the patients required spinal fusion at skeletal maturity (55% of our patients reached skeletal maturity). There was a gain in body weight (27.97 kg at preoperative time and 33.04 kg at postoperative time). The surgical complication rate was 32%. Conclusions: We recorded the stable correction of deformities and weight gain over time using the bipolar minimally invasive fusionless technique with a reduced rate of complication compared to arthrodesis. The arthrodesis was not necessary at skeletal maturity, thanks to the delayed natural ankylosis of a fixed spine.

Next generation phenotyping using narrative reports in a rare disease clinical data warehouse

BACKGROUND

Secondary use of data collected in Electronic Health Records opens perspectives for increasing our knowledge of rare diseases. The clinical data warehouse (named Dr. Warehouse) at the Necker-Enfants Malades Children's Hospital contains data collected during normal care for thousands of patients. Dr. Warehouse is oriented toward the exploration of clinical narratives. In this study, we present our method to find phenotypes associated with diseases of interest.

METHODS

We leveraged the frequency and TF-IDF to explore the association between clinical phenotypes and rare diseases. We applied our method in six use cases: phenotypes associated with the Rett, Lowe, Silver Russell, Bardet-Biedl syndromes, DOCK8 deficiency and Activated PI3-kinase Delta Syndrome (APDS). We asked domain experts to evaluate the relevance of the top-50 (for frequency and TF-IDF) phenotypes identified by Dr. Warehouse and computed the average precision and mean average precision.

RESULTS

Experts concluded that between 16 and 39 phenotypes could be considered as relevant in the top-50 phenotypes ranked by descending frequency discovered by Dr. Warehouse (resp. between 11 and 41 for TF-IDF). Average precision ranges from 0.55 to 0.91 for frequency and 0.52 to 0.95 for TF-IDF. Mean average precision was 0.79. Our study suggests that phenotypes identified in clinical narratives stored in Electronic Health Record can provide rare disease specialists with candidate phenotypes that can be used in addition to the literature.

CONCLUSIONS

Clinical Data Warehouses can be used to perform Next Generation Phenotyping, especially in the context of rare diseases. We have developed a method to detect phenotypes associated with a group of patients using medical concepts extracted from free-text clinical narratives.

Lower incidence of fracture after IV bisphosphonates in girls with Rett syndrome and severe bone fragility

BACKGROUND

Classic Rett Syndrome (RS) is a disabling condition mainly caused by MECP2 mutations. Girls with RS are at risk of developing bone fragility and fractures at a young age which results in pain and may seriously impair quality of life.

OBJECTIVE

To retrospectively assess the safety and efficacy of IV bisphosphonates on fracture, bone mineral density (BMD) and bone markers in RS girls with bone fragility.

METHODS

RS girls received either IV pamidronate (n = 19) or IV zoledronate (n = 1) for 2 years.

RESULTS

Of 20 patients studied (age: 12.5 years [6; 39]), 14 were non-ambulatory. The incidence of fracture decreased from 37 fractures in 20 patients, to 1 fracture during or after treatment (follow-up: 3.1 years [1.5; 5]). The spine BMD Z-score improved from -3.2 [-5.6; -0.1] to -2.2 [-3.8; 0.0], p = 0.0006. Most parents reported decreases in chronic pain and 2 patients started to walk. Urinary calcium excretion decreased from 0.7 [0.18; 1.5] to 0.2 [0.03; 0.67] mM/mM of creatinine (p = 0.0001). Pamidronate was well tolerated.

CONCLUSION

RS girls should be screened for impaired bone mineralization and preventive measures should be taken. In girls experiencing fractures, IV bisphosphonates constitute a beneficial adjuvant treatment to diminish the risk of fracture and restore bone density.

Outcome of childhood-onset epilepsy from adolescence to adulthood: Transition issues

This is the second of three papers that summarize the second symposium on Transition in Epilepsies held in Paris in June 2016. This paper addresses the outcome for some particularly challenging childhood-onset epileptic disorders with the goal of recommending the best approach to transition. We have grouped these disorders in five categories with a few examples for each. The first group includes disorders presenting in childhood that may have late- or adult-onset epilepsy (metabolic and mitochondrial disorders). The second group includes disorders with changing problems in adulthood (tuberous sclerosis complex, Rett syndrome, Dravet syndrome, and autism). A third group includes epilepsies that change with age (Childhood Absence Epilepsy, Juvenile Myoclonic Epilepsy, West Syndrome, and Lennox-Gastaut syndrome). A fourth group consists of epilepsies that vary in symptoms and severity depending on the age of onset (autoimmune encephalitis, Rasmussen's syndrome). A fifth group has epilepsy from structural causes that are less likely to evolve in adulthood. Finally we have included a discussion about the risk of later adulthood cerebrovascular disease and dementia following childhood-onset epilepsy. A detailed knowledge of each of these disorders should assist the process of transition to be certain that attention is paid to the most important age-related symptoms and concerns.

Phenotype Differentiation of FOXG1 and MECP2 Disorders: A New Method for Characterization of Developmental Encephalopathies

OBJECTIVE

To differentiate developmental encephalopathies by creating a novel quantitative phenotyping tool.

STUDY DESIGN

We created the Developmental Encephalopathy Inventory (DEI) to differentiate disorders with complex multisystem neurodevelopmental symptoms. We then used the DEI to study the phenotype features of 20 subjects with FOXG1 disorder and 11 subjects with MECP2 disorder.

RESULTS

The DEI identified core domains of fine motor and expressive language that were severely impaired in both disorders. Individuals with FOXG1 disorder were overall more severely impaired. Subjects with FOXG1 disorder were less able to walk, had worse fine motor skills, more disability in receptive language and reciprocity, and had more disordered sleep than did subjects with MECP2 disorder (P <.05). Covariance, cluster, and principal component analysis confirmed a relationship between impaired awareness, reciprocity, and language in both disorders. In addition, abnormal ambulation was a first principal component for FOXG1 but not for MECP2 disorder, suggesting that impaired ambulation is a strong differentiating factor clinically between the 2 disorders.

CONCLUSIONS

We have developed a novel quantitative developmental assessment tool for developmental encephalopathies and propose this tool as a method to identify and illustrate core common and differential domains of disability in these complex disorders. These findings demonstrate clear phenotype differences between FOXG1 and MECP2 disorders.