Pyridoxine-dependent epilepsy was recently shown to be due to mutations in the ALDH7A1 gene, which encodes antiquitin, an enzyme that catalyses the nicotinamide adenine dinucleotide-dependent dehydrogenation of l-α-aminoadipic semialdehyde/l-Δ1-piperideine 6-carboxylate. However, whilst this is a highly treatable disorder, there is general uncertainty about when to consider this diagnosis and how to test for it. This study aimed to evaluate the use of measurement of urine l-α-aminoadipic semialdehyde/creatinine ratio and mutation analysis of ALDH7A1 (antiquitin) in investigation of patients with suspected or clinically proven pyridoxine-dependent epilepsy and to characterize further the phenotypic spectrum of antiquitin deficiency. Urinary l-α-aminoadipic semialdehyde concentration was determined by liquid chromatography tandem mass spectrometry. When this was above the normal range, DNA sequencing of the ALDH7A1 gene was performed. Clinicians were asked to complete questionnaires on clinical, biochemical, magnetic resonance imaging and electroencephalography features of patients. The clinical spectrum of antiquitin deficiency extended from ventriculomegaly detected on foetal ultrasound, through abnormal foetal movements and a multisystem neonatal disorder, to the onset of seizures and autistic features after the first year of life. Our relatively large series suggested that clinical diagnosis of pyridoxine dependent epilepsy can be challenging because: (i) there may be some response to antiepileptic drugs; (ii) in infants with multisystem pathology, the response to pyridoxine may not be instant and obvious; and (iii) structural brain abnormalities may co-exist and be considered sufficient cause of epilepsy, whereas the fits may be a consequence of antiquitin deficiency and are then responsive to pyridoxine. These findings support the use of biochemical and DNA tests for antiquitin deficiency and a clinical trial of pyridoxine in infants and children with epilepsy across a broad range of clinical scenarios.

BACKGROUND: In addition to recurrent epileptic seizures, children with epilepsy can have coexisting cognitive and behavioral difficulties but the spectrum and prevalence of such difficulties are uncertain. METHODS: The Children with Epilepsy in Sussex Schools study is a prospective, community-based study involving school-aged children (5–15 years) with active epilepsy in a defined geographical area in the United Kingdom. Participants underwent comprehensive psychological assessment, including measures of cognition, behavior, and motor functioning. Consensus neurobehavioral diagnoses were made with respect to Diagnostic and Statistical Manual, Fourth Edition-Text Revision (DSM-IV-TR) criteria. RESULTS: A total of 85 children (74% of eligible population) were enrolled; 80% of children with active epilepsy had a DSM-IV-TR behavioral disorder and/or cognitive impairment (IQ <85). Intellectual disability (ID) (IQ <70) (40%), attention-deficit/hyperactivity disorder (ADHD) (33%), and autism spectrum disorder (ASD) (21%) were the most common neurobehavioral diagnoses. Of those who met criteria for a DSM-IV-TR behavioral disorder, only one-third had previously been diagnosed. Logistic regression revealed that seizures in the first 24 months compared with first seizures at 24 to 60 or 61+ months (odds ratio [OR] 13, 95% confidence interval 2.2–76.9; OR 21.3, 3.2–148.9) and polytherapy (OR 7.7, 1.6–36.3) were independently associated with ID and the presence of ID was associated with a diagnosis of ASD (OR 14.1, 2.3–87.1) after Bonferroni adjustment. Epilepsy-related factors did not independently predict the presence of behavioral disorders. CONCLUSIONS: Screening for neurobehavioral comorbidities should be an integral part of management in children with “active” epilepsy. There is a need for research to identify neurobiological mechanisms underpinning neurobehavioral impairments and studies to evaluate possible treatments.

SummaryBackgroundFacial port-wine stains (PWSs) are usually isolated findings; however, when associated with cerebral and ocular vascular malformations they form part of the classical triad of Sturge–Weber syndrome (SWS).ObjectivesTo evaluate the associations between the phenotype of facial PWS and the diagnosis of SWS in a cohort with a high rate of SWS.MethodsRecords were reviewed of all 192 children with a facial PWS seen in 2011–13. Adverse outcome measures were clinical (seizures, abnormal neurodevelopment, glaucoma) and radiological [abnormal magnetic resonance imaging (MRI)], modelled by multivariate logistic regression.ResultsThe best predictor of adverse outcomes was a PWS involving any part of the forehead, delineated at its inferior border by a line joining the outer canthus of the eye to the top of the ear, and including the upper eyelid. This involves all three divisions of the trigeminal nerve, but corresponds well to the embryonic vascular development of the face. Bilateral distribution was not an independently significant phenotypic feature. Abnormal MRI was a better predictor of all clinical adverse outcome measures than PWS distribution; however, for practical reasons guidelines based on clinical phenotype are proposed.ConclusionsFacial PWS distribution appears to follow the embryonic vasculature of the face, rather than the trigeminal nerve. We propose that children with a PWS on any part of the ‘forehead’ should have an urgent ophthalmology review and a brain MRI. A prospective study has been established to test the validity of these guidelines.What’s already known about this topic?Facial port-wine stains (PWSs) are common, but are rarely associated with Sturge–Weber syndrome (SWS).Early diagnosis of SWS is important to reduce ophthalmological and neural complications.Bilateral and ophthalmic division trigeminal nerve PWSs are thought to confer higher risk of SWS.What does this study add?The strongest predictor of SWS was found using a new classification of PWS based on the vascular embryological distribution and not the neural innervation of the face.We propose new guidelines for investigation of children with facial PWS based on this new classification of phenotype.