Loss-of-function mutations in UDP-Glucose 6-Dehydrogenase cause recessive developmental epileptic encephalopathy.

Developmental epileptic encephalopathies are devastating disorders characterized by intractable epileptic seizures and developmental delay. Here, we report an allelic series of germline recessive mutations in UGDH in 36 cases from 25 families presenting with epileptic encephalopathy with developmental delay and hypotonia. UGDH encodes an oxidoreductase that converts UDP-glucose to UDP-glucuronic acid, a key component of specific proteoglycans and glycolipids. Consistent with being loss-of-function alleles, we show using patients' primary fibroblasts and biochemical assays, that these mutations either impair UGDH stability, oligomerization, or enzymatic activity. In vitro, patient-derived cerebral organoids are smaller with a reduced number of proliferating neuronal progenitors while mutant ugdh zebrafish do not phenocopy the human disease. Our study defines UGDH as a key player for the production of extracellular matrix components that are essential for human brain development. Based on the incidence of variants observed, UGDH mutations are likely to be a frequent cause of recessive epileptic encephalopathy.

Anti-N-methyl-d-aspartate Receptor Encephalitis: A Case Series and Review of the Literature.

Anti-NMDAR (N-methyl-d-aspartate receptor) encephalitis is a potentially severe form of encephalitis associated with antibodies against NR1 and NR2 subunits of the NMDAR. Anti-NMDAR encephalitis is a treatable cause of encephalitis. An underlying tumor should be actively looked for as this is also considered to be a paraneoplastic syndrome. We report two children with anti-NMDAR encephalitis with a literature review of current evidence in diagnosing and managing this rare condition. Resection of the tumor, glucocorticoids, intravenous immunoglobulin, and plasma exchange often result in improvement, usually within four weeks. Outcome corresponds with the rapidity of commencing appropriate treatment.

Limbic encephalitis in a child: an atypical presentation.

BACKGROUND: Limbic encephalitis is a rare disorder with a generally subacute onset evolving over days to weeks. Patients present with a variable combination of memory loss, seizures, and psychiatric disturbance, and it is not rare for patients to be initially misdiagnosed. PATIENT: We describe a previously healthy 12-year-old boy who developed his first seizures at 8 years of age. He had a total of eight prolonged focal seizures, each followed by a month of behavioral changes and short-term memory loss. There was no family history of seizures or other neurological disorders, and he had an otherwise unremarkable neonatal and medical history. RESULTS: Magnetic resonance imaging during each episode of seizures showed alternating unilateral brain hemispheric involvement consistent with limbic encephalitis that was followed by resolution for a total of six times. Despite a negative laboratory evaluation for a large panel of paraneoplastic antibodies, the clinical scenario and exclusion of other possible disorders made recurrent limbic encephalitis the most likely diagnosis. CONCLUSION: Limbic encephalitis is a rare disorder that is diagnosed primarily on the basis of clinical criteria and is often associated with the presence of a paraneoplastic antibody. However, lack of a positive paraneoplastic antibody in a patient with a triad of seizure, behavioral changes, and short-term memory loss does not exclude the diagnosis. The unique presentation in a seronegative patient may indicate an unrecognized antibody.

Infantile osteopetrosis, craniosynostosis, and Chiari malformation type I with novel OSTEM1 mutation.

We report a case of a 9-month-old Arab infant, with novel OSTEM mutation and unpublished triad of osteopetrosis (OP), craniosynostosis (CS), and Chiari malformation type I (CM1). The index presented with progressive irritability, abnormal movements, following an accidental fall. The history revealed early onset of irritability, progressive visual loss, and global developmental delay, more prominent at the gross motor level and a suspected congenital cytomegalovirus infection. The pregnancy was uneventful with subsequent unremarkable delivery. The parents are Arabs'first cousins with no apparent symptoms or signs of bone disease. Three dimensional brain computed tomography (CT) showed ventriculomegaly, thick calvaria, and CS of the coronal and sagittal sutures. Patient had signs of left lower motor neuron facial palsy, and CT of petrous bones confirms the presence of osteopetrotic petrous with slim mastoid portions of the facial nerve canals both sides. Brain magnetic resonance imaging showed CM1. Skeletal survey showed sclerotic skeleton. He needed ventriculoperitoneal shunt and died at 18 months of age. Molecular testing for OSTEM1 gene revealed novel homozygous mutation that segregated from his parents. This novel OSTEM1 gene novel mutation and the combination of OP, infantile CS, and CM1 is to our knowledge never been reported.

Incidence of kidney stones with topiramate treatment in pediatric patients.

PURPOSE: We ran this study to assess the incidence of nephrolithiasis in a group of children on topiramate (TPM) therapy for at least 1 year. METHODS: In this retrospective observational surveillance study, we reviewed the medical charts of children on TPM for at least 1 year seen at the pediatric neurology department during the period from 2005 to 2010 at King Fahad Medical City. Children with a normal baseline ultrasound report were included. Follow-up ultrasound reports after at least 1 year were collected. However, patients with any evidence of chronic illness or medications that may affect the kidney functions in addition to those who are not compliant with the prescribed dose were excluded. Family history of renal stones, symptoms suggestive of urologic disorders, and comorbidities were recorded. KEY FINDINGS: Medical charts of 96 children on TPM with a mean age of 6.9 (±3.8) years were reviewed; 52 (54.2%) of the children were male. The follow-up ultrasound showed that five children (5.2%) had developed kidney stones. The occurrence of kidney stones was found in four female patients (80%) versus one male (20%) (p > 0.05). SIGNIFICANCE: Long-term use of TPM may result in increased incidence of asymptomatic kidney stones in the pediatric population. Hence, routine baseline and follow-up ultrasound of the urinary system should be recommended during the use of TPM in children.

Cockayne syndrome in three sisters with varying clinical presentation.

We report three sisters showing the clinical features and investigational findings of Cockayne syndrome (CS). In the rehabilitation unit of Northwest Armed Forces Hospital (N.W.A.F.H.), Tabuk, Saudi Arabia, there was a 12-year-old girl with typical features of CS. The girl had no apparent problems until the end of the first year when growth and developmental delay prompted medical evaluation. Brain CT, bone X-rays, auditory and ophthalmological evaluation confirmed the clinical impression of Cockayne syndrome. Two of her 13 sibs, both sisters, were later found to have the same syndrome. The sisters varied in clinical severity, as two of them had cataracts and early global delay and died early of inanition and infection. The third showed the disease manifestations at a relatively later age, did not have cataract, exhibited milder manifestations of the disease, and remains alive. The parents are not related by any way and the father is married to two other wives with 11 unaffected children. This report documents variable degrees of manifestations in sibs who presumably have the same gene mutation.