Genetics of Pediatric Epilepsy: Next-Generation Sequencing in Clinical Practice.

Epilepsy is one of the most common neurological disorders with diverse phenotypic characteristics and high genetic heterogeneity. Epilepsy often occurs in childhood, so timely diagnosis and adequate therapy are crucial for preserving quality of life and unhindered development of a child. Next-generation-sequencing (NGS)-based tools have shown potential in increasing diagnostic yield. The primary objective of this study was to evaluate the impact of genetic testing and to investigate the diagnostic utility of targeted gene panel sequencing. This retrospective cohort study included 277 patients aged 6 months to 17 years undergoing NGS with an epilepsy panel covering 142 genes. Of 118 variants detected, 38 (32.2%) were not described in the literature. We identified 64 pathogenic or likely pathogenic variants with an overall diagnostic yield of 23.1%. We showed a significantly higher diagnostic yield in patients with developmental delay (28.9%). Furthermore, we showed that patients with variants reported as pathogenic presented with seizures at a younger age, which led to the conclusion that such children should be included in genomic diagnostic procedures as soon as possible to achieve a correct diagnosis in a timely manner, potentially leading to better treatment and avoidance of unnecessary procedures. Describing and discovering the genetic background of the disease not only leads to a better understanding of the mechanisms of the disorder but also opens the possibility of more precise and individualized treatment based on stratified medicine.

Infantile spasms in children with Down syndrome.

Down syndrome (DS) is the most common genetic cause of mental retardation. It is estimated that 5-13% of persons affected by DS have seizures. Infantile spasms are the most common type of seizures and usually are well controlled with steroids and antiepileptic drugs. We present 11 children at the age of 3 years and 4 months to 10 years and 7 months with DS and infantile spasms, treated at Children's Hospital Zagreb from January 2000 until July 2009. Infantile spasms began at the age of 5 to 10.5 months in 10 children, in one child at the age of 16 months. Only one child had perinatal risk factors for the development of IS. Changes in EEG correlated to hypsarrhythmia. Infantile spasms were treated initially with antiepileptic drugs, most often with valproic acid. Treatment was inefficient in 10/11 patients. After application of ACTH, infantile spasms stopped between 7 and 15 days in 6 patients, until 28th day in 4 patients. Hypsarrhythmia vanished in all children. During follow-up period (2 years and 7 months to 9 years and 5 months) none of the children developed another type of seizures. No major epileptogenic changes were registered in EEG. Antiepileptic therapy was discontinued in 4 children (aged 4 years and 2 months to 5 years). In this group is the boy who died of heart failure. Infantile spasms associated with DS are categorized into symptomatic group. The existence of cerebral pathology and delayed psycho-motor development precedes occurrence of seizures. It is possible to achieve good control of seizures and disappearance of hypsarrhythmia with application of ACTH and antiepileptic drugs.

Lenticulostriatal vasculopathy - a marker for congenital cytomegalovirus infection?

Lenticulostriate vasculopathy (LSV) is an ultrasound (US) visible lesion of the brain, which appears as echogenic streaks or spots in the arteries of thalamus and basal ganglia. LSV has varied etiology. Transfontanelar Color Doppler (TFCD) can easily display lenticulostriatal blood flow and assess: stage I LSV with present flow within echogenic changes and stage II LSV in which the flow disappears, despite a presence of streaks and spots, which at this stage most probably correspond to calcification. The objectives of this study are to determine: (1) Whether there are differences in distribution (unilateral or bilateral) and presence (during first year of age) of TFCD flow between congenital CMV infection positive and negative group of children with LSV (2) Could US and TFCD findings of LSV be an indication for further investigation of possible congenital CMV infection, because of their variable and often adverse neurodevelopmental outcome? We examined and followed-up 98 infants with LSV One group (37/98) with congenital CMV infection and second (61/98) negative. All infants had clinical signs of neuromotor delay and ultrasound and TFCD markers of LSV Our study shows that most of the patients from both groups had TFCD visible flow at the age of 0-4 months. In majority of them in both groups, at the age of 5-8 months, there was no more visible flow. TFCD showed no statistically significant difference among congenital CMV infection positive group and negative group, nor in youngest age period (0-4 months), nor in later course of flow in LSV unilaterally or bilaterally. Although the LSV presents nonspecific marker for intracranial infection (ICI), all infants presenting with LSV should be evaluated for possible ICI. Thus, the Doppler findings of LSV in infants require a detailed examination, monitoring and follow-up of neuromotor outcome.

Malformations of cortical development in children with congenital cytomegalovirus infection - A study of nine children with proven congenital cytomegalovirus infection.

Congenital cytomegalovirus (CMV) infection is the most common vertically transmitted disease with the rate of the infection ranging from 0.2 to 2.4% in newborn infants. Congenital CMV infection causes multiorgan affection, but the most severe and permanent sequelae are those affecting central nervous system such as mental retardation, cerebral palsy, sensorineural hearing loss, chorioretinitis and seizures as a result of direct interference of the virus with neurogenesis. The time of acquiring infection is strongly connected to the level of child's disability. Infection in early pregnancy results in severe neurological sequelae, while later infection has less prominent signs. Radiological findings show connection between onset of infection and brain imaging, from lissencephaly, pachygyria, polymicrogyria, schizencephaly, calcification, cerebellar hypoplasia and/or hypoplasia/agenesis of corpus callosum as a result of an early infection, to white matter abnormalities including disturbed myelination as a result of a late infection. We present nine patients with proven congenital CMV infection and malformations of cortical development and their computed tomography/magnetic resonance (CT/MRI) findings along with clinical assessments. According to CT/MRI results we assume that two of our children with lissencephaly had an early onset of infection. The other seven with less severe cortical dysplasia in form of pachy/polymicrogyria were probably infected later Cerebellar hypoplasia and/or calcifications in our patients also confirm an early onset of infection. Developmental outcome in all of our children was poor: moderate to severe psychomotor retardation has been diagnosed in all children; five of them have developed cerebral palsy (four have bilateral spastic and one dyskinetic) and one is estimated to have minor motor dysfunction. Seven out of nine developed epilepsy, chorioretinitis was found in three of them and sensorineural deafness in two of them. All of our children, except one, were presented by symptomatic infection, yet only four of them were recognized at birth. Therefore, congenital CMV infection should be considered as one of the reasons for childhood disability more often.

[Diagnostic procedures in pediatric migraine]. / Dijagnosticki postupci kod migrenskih glavobolja u djecjoj dobi.

The "gold standard" in the diagnosis of pediatric migraine includes personal history, clinical and neurological examination. Many important data on previous morbidity, psychosocial status and recent sickness (today's headache) can be found by using an interview, "face to face", or by "headache diary". On clinical examination, it is important to pay due attention to cardiovascular and respiratory systems as well as to examination of the skin. Thorough neurological examination may reveal disturbances of the mental status, cranial nerves, motor and sensory systems, reflexes, coordination and visual status. Acute headache without febrile illness and neurological disturbances is very indicative on childhood migraine or "migraine variants". However, due to many secondary headaches with migraine-like symptoms, it is important to perform detailed diagnostic protocol including computerized tomography, magnetic resonance imaging, electroencephalography, transcranial color doppler, laboratory tests and toxicological screening. Neuroimaging is indicated in children with acute headache, chronic progressive headache, especially if associated with vomiting, nausea or neurological disturbances, papillary edema, and in children with personality changes, learning difficulties and those under five years of age.

Ataxia Telangiectasia and Juvenile Idiopathic Arthritis.

We report, to the best of our knowledge, the first case of a child with typical ataxia telangiectasia (A-T) who developed juvenile idiopathic arthritis (JIA). The patient was a 15-year-old boy with A-T who presented with noninfectious polyarthritis. A-T is a rare, autosomal recessive disorder characterized by cerebellar atrophy, oculocutaneous telangiectasia, immunodeficiency, radiosensitivity, and predisposition to cancer. The gene responsible for A-T is the A-T mutated (ATM) gene. Clinical manifestations of the disorder are the result of lacking ATM protein, which is involved in DNA repair, apoptosis, various checkpoints in the cell cycle, gene regulation, translation, initiation, and telomere maintenance. There are a few articles that describe deficiency of the DNA repair enzyme, ATM, in rheumatoid arthritis, but the connection between the absence of ATM protein and JIA has not been presented or studied yet. JIA is a heterogeneous group of diseases characterized by arthritis of unknown origin with onset before the age of 16 years. It is the most common childhood chronic rheumatic disease and causes significant disability. Because immunodeficiency can be part of A-T, infectious arthritis can occur, but chronic autoimmune arthritis in these patients is rare. We report a rare case of a 15-year-old boy with A-T and JIA. This case shows a possible relationship between altered function of ATM protein and the pathogenesis of JIA.