Clinical and genetic features of 13 Spanish patients with KCNQ2 mutations.

The KCNQ2 gene codifies a subunit of the voltage-gated potassium M channel underlying the neuronal M-current. Classically, mutations in this gene have been associated with benign familial neonatal seizures, however, in recent years KCNQ2 mutations have been reported associated to early-onset epileptic encephalopathy. In this work, detailed familiar, clinical and genetic data were collected for 13 KCNQ2-positive patients revealed among a cohort of 80 epileptic pediatric probands from Spain who were analyzed through a targeted next-generation sequencing assay for 155 epilepsy-associated genes. This work shows for the first time the association between KCNQ2 mutations and startle attacks in 38% of patients, which opens the possibility to define electroclinical phenotypes associated to KCNQ2 mutations. It also demonstrates that KCNQ2 mutations contribute to an important percentage of Spanish patients with epilepsy. The study confirm the high genetic heterogeneity of this gene with 13 different mutations found, 10 of them novel and the better outcome of patients treated with sodium channel blockers.

Neonatal arterial stroke location is associated with outcome at 2 years: a voxel-based lesion-symptom mapping study.

OBJECTIVE: In contrast to motor impairments, the association between lesion location and cognitive or language deficits in patients with neonatal arterial ischaemic stroke remains largely unknown. We conducted a voxel-based lesion-symptom mapping cross-sectional study aiming to reveal neonatal arterial stroke location correlates of language, motor and cognitive outcomes at 2 years of age. DESIGN: Prospective observational multicentre study. SETTING: Six paediatric university hospitals in Spain. PARTICIPANTS: We included 53 patients who had a neonatal arterial ischaemic stroke with neonatal MRI and who were followed up till 2 years of age. MAIN OUTCOME MEASURES: We analysed five dichotomous clinical variables: speech therapy (defined as the need for speech therapy as established by therapists), gross motor function impairment, and the language, motor and cognitive Bayley scales. All the analyses were controlled for total lesion volume. RESULTS: We found that three of the clinical variables analysed significantly correlated with neonatal stroke location. Speech therapy was associated with lesions located mainly at the left supramarginal gyrus (p=0.007), gross motor function impairment correlated with lesions at the left external capsule (p=0.044) and cognitive impairment was associated with frontal lesions, particularly located at the left inferior and middle frontal gyri (p=0.012). CONCLUSIONS: The identification of these susceptible brain areas will allow for more precise prediction of neurological impairments on the basis of neonatal brain MRI.

Usefulness of video recordings for validating neonatal encephalopathy exams: a population-based cohort study.

OBJECTIVE: To determine the usefulness of video recordings for validating neonatal encephalopathy (NE) exams. DESIGN: Population-based prospective cohort study. NE was assessed and recorded at 1, 3 and 5 hours after birth by the attending physician. Recordings were reviewed blindly after the recruitment period by two specialists. Outcome was assessed at 36 months of age. SETTING: Twelve intensive care units in Spain. PATIENTS: Infants of ≥35 weeks' gestational age with perinatal asphyxia. MAIN OUTCOMES MEASURES: Weighted kappa to measure disagreement between the two specialists and between the attending physician and the specialists' classification agreed on by consensus. Regression models to test the association of disagreement on NE assessment and outcome. RESULTS: Of the 32 325 liveborn infants, 217 met the inclusion criteria. Video-recordings were not available for 43 infants (20%). Weighted kappa statistic was 0.74 (95% CI 0.67 to 0.81) between the specialists and the attending physicians. Disagreement occurred in 93 of the 417 (22%) videos, specifically in 39 (14%), 43 (47%), 11 (34%) and 0 exams categorised as no, mild, moderate and severe NE, respectively. According to the specialist consensus assessment, there was disagreement on the therapeutic hypothermia decision in 10 infants.When there was consensus among the specialists assessing a more severe NE degree compared with the attending physicians in 170 infants, those infants had lower cognitive scores with a median of -5.33 points (95% CI -9.85 to -8.16; p=0.02). CONCLUSIONS: This study supports the feasibility and benefit of using video recordings to identify NE in infants with perinatal asphyxia.

Lack of Variability in Cerebral Oximetry Tendency in Infants with Severe Hypoxic-Ischemic Encephalopathy Under Hypothermia.

Cerebral oximetry using near-infrared spectroscopy (NIRS) provides continuous, noninvasive assessment of the degree of hemoglobin saturation of the brain tissue. Previous studies suggest that high values of regional cerebral tissue oxygen saturation (rScO2) during the first days in neonates with significant hypoxic-ischemic encephalopathy (HIE) are correlated with an adverse neurological outcome. However, the results are not consistent among the studies. To examine the correlation of rScO2 values and their variability over time with HIE severity, amplitude integrated electroencephalography (aEEG) background and seizure activity, neuron-specific enolase levels in cerebrospinal fluid, magnetic resonance imaging (MRI) findings, and neurological outcome. Retrospective study that included all consecutive infants with moderate-to-severe HIE born at ≥35 weeks gestational age admitted between January 2011 and December 2014. NIRS monitoring was initiated at admission and maintained during therapeutic hypothermia up to 12 hours after rewarming. To analyze rScO2, different periods (0-6, 6-24, 24-48, 48-72, and 72-100 hours of life) and three ranges (<55%, 55-90%, >90%) were considered. Variability in each patient was considered ≤5% when changes in rScO2 values in all periods were ≤5%. Twenty-three newborns were included. Infants who suffered from severe HIE, seizures, abnormal aEEG background, altered MRI or death, and abnormal outcome had rScO2 values >90% and with less variability (≤5%). rScO2 values >90% and a lack of variability over time in infants with HIE during cooling provide useful information about the severity of neurological status.

Prenatal and Perinatal Morbidity in Children with Tic Disorders: A Mainstream School-based Population Study in Central Spain.

BACKGROUND: While current research suggests that genetic factors confer the greatest risk for the development of tic disorders, studies of environmental factors are relatively few, with a lack of consistent risk factors across studies. Our aim is to analyze the association of tic disorders with exposure to prenatal and perinatal morbidity. METHODS: This was a nested case-control study design. Cases and controls were selected and identified from a mainstream, school-based sample. The diagnosis of tic disorders was assigned by a movement disorder neurologist using 'Diagnostic and statistical manual of mental disorders, 4th edition, text revision' criteria, and neuropsychiatric comorbidities were screened using the Spanish computerized version of the Diagnostic Interview Schedule for Children Predictive Scale. Information regarding the exposure to pre-perinatal risk factors was collected by a retrospective review of the birth certificates. Logistic regression analyses were then performed to test the association of tic disorders with pre-perinatal risk factors. RESULTS: Out of 407 participants, complete pre-perinatal data were available in 153 children (64 with tics and 89 without tics). After adjusting for family history of tics, neonatal respiratory distress syndrome, body mass index, prenatal infection, and coexisting comorbid neuropsychiatric disturbances, tic disorders were associated with prenatal exposure to tobacco (odds ratio [OR] = 3.07, 95% confidence interval [CI] 1.24-7.60, p = 0.007), and cesarean section (OR = 5.78, 95% CI 1.60-20.91, p = 0.01). DISCUSSION: This nested case-control study of children with tic disorders demonstrates higher adjusted odds for tics in children with exposure to cesarean delivery and maternal smoking. Longitudinal, population-based samples are required to confirm these results.