International telemedicine consultations for neurodevelopmental disabilities

Background: A telemedicine program was developed between the Children\u27s National Medical Center (CNMC) in Washington, DC, and the Sheikh Khalifa Bin Zayed Foundation in the United Arab Emirates (UAE). A needs assessment and a curriculum of on-site training conferences were devised preparatory to an ongoing telemedicine consultation program for children with neurodevelopmental disabilities in the underserved eastern region of the UAE. Materials and Methods: Weekly telemedicine consultations are provided by a multidisciplinary faculty. Patients are presented in the UAE with their therapists and families. Real-time (video over Internet protocol; average connection, 768 kilobits/s) telemedicine conferences are held weekly following previews of medical records. A full consultation report follows each telemedicine session. Results: Between February 29, 2012 and June 26, 2013, 48 weekly 1-h live interactive telemedicine consultations were conducted on 48 patients (28 males, 20 females; age range, 8 months–22 years; median age, 5.4 years). The primary diagnoses were cerebral palsy, neurogenetic disorders, autism, neuromuscular disorders, congenital anomalies, global developmental delay, systemic disease, and epilepsy. Common comorbidities were cognitive impairment, communication disorders, and behavioral disorders. Specific recommendations included imaging and DNA studies, antiseizure management, spasticity management including botulinum toxin protocols, and specific therapy modalities including taping techniques, customized body vests, and speech/language and behavioral therapy. Improved outcomes reported were in clinician satisfaction, achievement of therapy goals for patients, and requests for ongoing sessions. Conclusions: Weekly telemedicine sessions coupled with triannual training conferences were successfully implemented in a clinical program dedicated to patients with neurodevelopmental disabilities by the Center for Neuroscience at CNMC and the UAE government. International consultations in neurodevelopmental disabilities utilizing telemedicine services offer a reliable and productive method for joint clinical programs

Treatment of Inborn Errors of Urea Synthesis — Activation of Alternative Pathways of Waste Nitrogen Synthesis and Excretion

Abstract Children with inborn errors of urea synthesis accumulate ammonium and other nitrogenous precursors of urea, leading to episodic coma and a high mortality rate. We used alternative pathways for the excretion of waste nitrogen as substitutes for the defective ureagenic pathways in 26 infants. These pathways involve synthesis and excretion of hippurate after sodium benzoate administration, and of citrulline and argininosuccinate after arginine supplementation. The children were treated for seven to 62 months; 22 survived. The mean plasma level of ammonium (±S.E.) was 36±2 μmol per liter, and that of benzoate was 1.5±1.0 mg per deciliter. Alternative pathways accounted for between 28 and 59 per cent of the total effective excretion of waste nitrogen. Nineteen infants had normal height, weight, and head circumference, and 13 had normal intellectual development. Activation of alternative pathways of waste nitrogen excretion can prolong survival and improve clinical outcome in children with inborn errors of urea synthesis. (N Engl J Med. 1982; 306:1387–92.

A dual AAV system enables the Cas9-mediated correction of a metabolic liver disease in newborn mice

Many genetic liver diseases present in newborns with repeated, often lethal, metabolic crises. Gene therapy using non-integrating viruses such as AAV is not optimal in this setting because the non-integrating genome is lost as developing hepatocytes proliferate1,2. We reasoned that newborn liver may be an ideal setting for AAV-mediated gene correction using CRISPR/Cas9. Here we intravenously infuse two AAVs, one expressing Cas9 and the other expressing a guide RNA and the donor DNA, into newborn mice with a partial deficiency in the urea cycle disorder enzyme, ornithine transcarbamylase (OTC). This resulted in reversion of the mutation in 10% (6.7% – 20.1%) of hepatocytes and increased survival in mice challenged with a high-protein diet, which exacerbates disease. Gene correction in adult OTC-deficient mice was lower and accompanied by larger deletions that ablated residual expression from the endogenous OTC gene, leading to diminished protein tolerance and lethal hyperammonemia on a chow diet

Children with Disabilities

xxxv, 868 p.; ill.; 23 cm

A longitudinal study of urea cycle disorders

The urea cycle disorders consortium (UCDC) is a member of the NIH funded Rare Diseases Clinical Research Network and is performing a longitudinal study of 8 urea cycle disorders (UCD) with initial enrollment beginning in 2006. The consortium consists of 14 sites in the U.S., Canada and Europe. This report summarizes data mining studies of 614 patients with UCD enrolled in the UCDC’s longitudinal study protocol. The most common disorder is ornithine transcarbamylase deficiency, accounting for more than half of the participants. We calculated the overall prevalence of urea cycle disorders to be 1/35,000, with 2/3rds presenting initial symptoms after the newborn period. We found the mortality rate to be 24% in neonatal onset cases and 11% in late onset cases. The most common precipitant of clinical hyperammonemic episodes in the post-neonatal period was intercurrent infections. Elevations in both blood ammonia and glutamine appeared to be biomarkers for neurocognitive outcome. In terms of chronic treatment, low protein diet appeared to result in normal weight but decreased linear growth while N-scavenger therapy with phenybutyrate resulted in low levels of branched chain amino acids. Finally, we found an unexpectedly high risk for hepatic dysfunction in patients with ornithine transcarbamylase deficiency. This natural history study illustrates how a collaborative study of a rare genetic disorder can result in an improved understanding of morbidity and disease outcome