Study of genetic variants and their clinical significance in Mexican pediatric patients with epilepsy.

BACKGROUND: The use of novel and accurate techniques to identify genetic variants (with or without a record in the National Center for Biotechnology Information (NCBI) database) improves diagnosis, prognosis, and therapeutics for patients with epilepsy, especially in populations for whom such techniques exist. The aim of this study was to find a genetic profile in Mexican pediatric epilepsy patients by focusing on ten genes associated with drug-resistant epilepsy (DRE). METHODS: This was a prospective, analytical, cross-sectional study of pediatric patients with epilepsy. Informed consent was granted by the patients' guardians or parents. Genomic DNA from the patients was sequenced using next-generation sequencing (NGS). For statistical analysis, Fisher's exact, Chi-square or Mann-Whitney U, and OR (95% CI) tests were performed, with significance values of p < 0.05. RESULTS: Fifty-five patients met the inclusion criteria (female 58.2%, ages 1-16 years); 32 patients had controlled epilepsy (CTR), and 23 had DRE. Four hundred twenty-two genetic variants were identified (71.3% with a known SNP registered in the NCBI database). A dominant genetic profile consisting of four haplotypes of the SCN1A, CYP2C9, and CYP2C19 genes was identified in most of the patients studied. When comparing the results between patients with DRE and CTR, the prevalence of polymorphisms in the SCN1A (rs10497275, rs10198801, and rs67636132), CYP2D6 (rs1065852), and CYP3A4 (rs2242480) genes showed statistical significance (p = 0.021). Finally, the number of missense genetic variants in patients in the nonstructural subgroup was significantly higher in DRE than in CTR (1 [0-2] vs. 3 [2-4]; p = 0.014). CONCLUSIONS: The Mexican pediatric epilepsy patients included in this cohort presented a characteristic genetic profile infrequent in the Mexican population. SNP rs1065852 (CYP2D6*10) is associated with DRE, especially with nonstructural damage. The presence of three genetic alterations affecting the CYP2B6, CYP2C9, and CYP2D6 cytochrome genes is associated with nonstructural DRE.

Calcinosis cutis congénita tumoral asociada con encefalopatía epiléptica infantil temprana con variante patogénica en el gen FGF12 / Tumorous congenital calcinosis cutis associated with early childhood epileptic encephalopathy with a pathogenic FGF12 gene variant

Resumen Introducción: La calcinosis cutis es el depósito de sales insolubles de calcio en la piel y se clasifica, de acuerdo con su patogénesis, en distrófica, metastásica, idiopática, iatrogénica y calcifilaxis. La calcinosis idiopática se presenta en pacientes sanos y es asintomática; incluye la calcinosis escrotal, la calcinosis nodular de Winer o nódulos calcificados subepidérmicos y la calcinosis tumoral familiar. Esta última es una condición rara que se caracteriza por el depósito de calcio periarticular en pacientes normocalcémicos sin conexión al hueso. Caso clínico: Paciente de sexo masculino de 5 meses de edad, quien al séptimo día de vida fue hospitalizado por ictericia multifactorial, sepsis neonatal tardía y apnea con crisis epilépticas. La evolución fue tórpida, con ingresos hospitalarios por crisis epilépticas de difícil manejo, respuesta parcial a la difenilhidantoína y descontrol electrolítico. Mediante la secuenciación del exoma dirigido se detectó una variante patogénica de sentido equivocado en FGF12 que confirmó el diagnóstico de encefalopatía epiléptica temprana número 47. Además, el paciente presentó dermatosis congénita diseminada a las extremidades inferiores con afección en muslos, asintomática, bilateral y simétrica, constituida por hipopigmentación y fóveas duras a la palpación profunda. La biopsia mostró calcificación distrófica. Conclusiones: Se presenta el caso de un lactante con calcinosis cutis congénita profunda asociada con una variante patogénica en el gen FGF12 y con encefalopatía epiléptica, situación clínica que, a la fecha, no había sido reportada en la literatura.

Abstract Background: Calcinosis cutis is the deposit of insoluble calcium salts in the skin. It is classified according to its pathogenesis in dystrophic, metastatic, idiopathic, iatrogenic, and calciphylaxis. Idiopathic calcinosis is asymptomatic, occurs in healthy patients, and includes scrotal calcinosis, Winer's nodular calcinosis or subepidermal calcified nodules, and familial tumor calcinosis. The latter is a rare condition characterized by periarticular calcium deposition in normocalcemic patients with no bone connection. Case report: The case of a 5-month-old male patient, who on the seventh day of life was hospitalized for multifactorial jaundice, late neonatal sepsis, and apnea with epileptic seizures is described. His evolution was torpid, with hospital admissions due to epileptic seizures that were difficult to manage with partial response to the use of diphenylhydantoin and electrolyte alterations. By means of exome sequencing directed, a pathogenic variant of wrong direction in FGF12 was detected and the diagnosis of early epileptic encephalopathy number 47 was confirmed. Also, the patient showed disseminated congenital dermatosis to lower extremities affecting thighs, asymptomatic, bilateral and symmetrical, constituted by hypopigmentation and fovea hard to deep palpation. The biopsy showed dystrophic calcification Conclusions: The case of an infant with deep congenital cutis calcinosis associated with a pathogenic variant in the FGF12 gene with epileptic encephalopathy is described. To date, this clinical situation has not been previously reported in the literature.

Tumorous congenital calcinosis cutis associated with early childhood epileptic encephalopathy with a pathogenic FGF12 gene variant.

Background: Calcinosis cutis is the deposit of insoluble calcium salts in the skin. It is classified according to its pathogenesis in dystrophic, metastatic, idiopathic, iatrogenic, and calciphylaxis. Idiopathic calcinosis is asymptomatic, occurs in healthy patients, and includes scrotal calcinosis, Winer's nodular calcinosis or subepidermal calcified nodules, and familial tumor calcinosis. The latter is a rare condition characterized by periarticular calcium deposition in normocalcemic patients with no bone connection. Case report: The case of a 5-month-old male patient, who on the seventh day of life was hospitalized for multifactorial jaundice, late neonatal sepsis, and apnea with epileptic seizures is described. His evolution was torpid, with hospital admissions due to epileptic seizures that were difficult to manage with partial response to the use of diphenylhydantoin and electrolyte alterations. By means of exome sequencing directed, a pathogenic variant of wrong direction in FGF12 was detected and the diagnosis of early epileptic encephalopathy number 47 was confirmed. Also, the patient showed disseminated congenital dermatosis to lower extremities affecting thighs, asymptomatic, bilateral and symmetrical, constituted by hypopigmentation and fovea hard to deep palpation. The biopsy showed dystrophic calcification. Conclusions: The case of an infant with deep congenital cutis calcinosis associated with a pathogenic variant in the FGF12 gene with epileptic encephalopathy is described. To date, this clinical situation has not been previously reported in the literature.

Background: Introducción">La calcinosis cutis es el depósito de sales insolubles de calcio en la piel y se clasifica, de acuerdo con su patogénesis, en distrófica, metastásica, idiopática, iatrogénica y calcifilaxis. La calcinosis idiopática se presenta en pacientes sanos y es asintomática; incluye la calcinosis escrotal, la calcinosis nodular de Winer o nódulos calcificados subepidérmicos y la calcinosis tumoral familiar. Esta última es una condición rara que se caracteriza por el depósito de calcio periarticular en pacientes normocalcémicos sin conexión al hueso. Caso clínico: Paciente de sexo masculino de 5 meses de edad, quien al séptimo día de vida fue hospitalizado por ictericia multifactorial, sepsis neonatal tardía y apnea con crisis epilépticas. La evolución fue tórpida, con ingresos hospitalarios por crisis epilépticas de difícil manejo, respuesta parcial a la difenilhidantoína y descontrol electrolítico. Mediante la secuenciación del exoma dirigido se detectó una variante patogénica de sentido equivocado en FGF12 que confirmó el diagnóstico de encefalopatía epiléptica temprana número 47. Además, el paciente presentó dermatosis congénita diseminada a las extremidades inferiores con afección en muslos, asintomática, bilateral y simétrica, constituida por hipopigmentación y fóveas duras a la palpación profunda. La biopsia mostró calcificación distrófica. Conclusiones: Se presenta el caso de un lactante con calcinosis cutis congénita profunda asociada con una variante patogénica en el gen FGF12 y con encefalopatía epiléptica, situación clínica que, a la fecha, no había sido reportada en la literatura.

Influence of genetic variants of CYP2D6, CYP2C9, CYP2C19 and CYP3A4 on antiepileptic drug metabolism in pediatric patients with refractory epilepsy.

BACKGROUND: Identified the polymorphisms of CYP2D6, CYP2C9, CYP2C19 and CYP3A4, within a rigorously selected population of pediatric patients with drug-resistant epilepsy. METHOD: The genomic DNA of 23 drug-resistant epilepsy patients and 7 patients with good responses were analyzed. Ten exons in these four genes were genotyped, and the drug concentrations in saliva and plasma were determined. RESULTS: The relevant SNPs with pharmacogenomics relations were CYP2D6*2 (rs16947) decreased your activity and CYP2D6*4 (rs1065852), CYP2C19*2 (rs4244285) and CYP3A4*1B (rs2740574) by association with poor metabolizer. The strongest risk factors were found in the AA genotype and allele of SNP rs3892097 from the CYP2D6 gene, followed by the alleles A and T of SNPs rs2740574 and rs2687116, respectively from CYP3A4. The most important concomitance was between homozygous genotype AA of rs3892097 and genotype AA of rs2740574 with 78.3% in drug-resistant epilepsy patients as compared to 14.3% in control patients. CONCLUSION: The results demonstrated the important role of the CYP 3A4*1B allelic variant as risk factor for developing drug resistance and CYP2D6, CYP2C19 SNPs and haplotypes may affect the response to antiepileptic drugs.

MDR-1 and MRP2 Gene Polymorphisms in Mexican Epileptic Pediatric Patients with Complex Partial Seizures.

Although the Pgp efflux transport protein is overexpressed in resected tissue of patients with epilepsy, the presence of polymorphisms in MDR1/ABCB1 and MRP2/ABCC2 in patients with antiepileptic-drugs resistant epilepsy (ADR) is controversial. The aim of this study was to perform an exploratory study to identify nucleotide changes and search new and reported mutations in patients with ADR and patients with good response (CTR) to antiepileptic drugs (AEDs) in a rigorously selected population. We analyzed 22 samples In Material and Methods, from drug-resistant patients with epilepsy and 7 samples from patients with good response to AEDs. Genomic DNA was obtained from leukocytes. Eleven exons in both genes were genotyped. The concentration of drugs in saliva and plasma was determined. The concentration of valproic acid in saliva was lower in ADR than in CRT. In ABCB1, five reported SNPs and five unreported nucleotide changes were identified; rs2229109 (GA) and rs2032582 (AT and AG) were found only in the ADR. Of six SNPs associated with the ABCC2 that were found in the study population, rs3740066 (TT) and 66744T > A (TG) were found only in the ADR. The strongest risk factor in the ABCB1 gene was identified as the TA genotype of rs2032582, whereas for the ABCC2 gene the strongest risk factor was the T allele of rs3740066. The screening of SNPs in ACBC1 and ABCC2 indicates that the Mexican patients with epilepsy in this study display frequently reported ABCC1 polymorphisms; however, in the study subjects with a higher risk factor for drug resistance, new nucleotide changes were found in the ABCC2 gene. Thus, the population of Mexican patients with AED-resistant epilepsy (ADR) used in this study exhibits genetic variability with respect to those reported in other study populations; however, it is necessary to explore this polymorphism in a larger population of patients with ADR.

[Rasnmussen syndrome. 7 years' follow-up. Aspects related to cerebral plasticity in epilepsy]. / Síndrome de Rasmussen. Seguimiento de siete años. Aspectos relacionados con plasticidad cerebral en epilepsia.

Present study represents a case follow up for seven years. A case of Epilepsy Partialis Continua (EPC) in a fifteen year old girl was studied with CT, MRI, cerebral SPECT and constantly EEG procedures: The SPECT study showed in right frontal lobe and right temporal lobe hypoperfusion (reduction of regional cerebral blood flow [rCBF]) cerebral zone in the interictal period and hyperperfusion (increase rCBF) in the ictal period in the same hemisphere. The EEG showed abnormal activity consisting in sharp wave and polyphasic sharp wave in frontal and temporal regions. The medical treatment was refractory at all kind of anticonvulsant drugs. In order to improve the refractory epilepsy the team decided an epilepsy surgery with right temporal lobotomy and right frontal corticetomy. This procedure were done at the eight year old and the results were satisfactory immediately after the surgery with absolute control and normal cognitive performance two weeks later the surgery. This patient was follow up for seven years with EEG constantly with normal activity, SPECT and MRI, all studies showed functional hemispherectomy, total absence in the structure and cerebral blood flow in right hemisphere with normal perfusion and structure in left hemisphere. The late control of neuropsychology assessment showed some deficits in the I.Q. cognitive performance, evaluated by the Weschler scale and Machover tests. These findings would be able to demonstrate a phenomenon of brain plasticity and neuronal restoration in the left cerebral hemisphere after to remove the abnormal cerebral epilepsy focus. This procedure might permits the restoration of inadequate neuronal environment and normalization of neural physiological stability. The postulated mechanisms of reorganization of function are unmasking, nonsynaptic diffusion neurotransmission and receptor plasticity, trophic factors, synapsins and neurotransmitters. The neuropsychological mechanism to preserve the functions would be involving in a cortical reorganization with axonal and dendritic development beside sprouting and synaptogenesis. This patient is a good example of neuronal plasticity in epilepsy surgery.

Toxina botulínica como tratamiento de la espasticidad y distonía en la parálisis cerebal infantil / Botulinum toxin as a treatment for spasticity and Ddystonia in Pediatric Cerebral Palsy

Manejo de la espasticidad y diston'a en la PCI con toxina botul'nica tipo A.Introducción.- La toxina botulínica tipo A (NxTx Bo A) se ha usado en la terapia del estrabismo, distonías y espasticidad. Objetivo.- Evaluar la efectividad de la NxTx Bo A en pacientes con parálisis cerebral infantil (PCI) espástica y/o distónica. Material y Métodos.- Se trataron prospectivamente 12 pacientes con al menos 2 dosis de NxTxBoA en los músculos afectados durante 12 meses. Ocho espásticos y cuatro espásticos-distónicos. Las indicaciones fueron: mejorar funcionalidad de las extremidades espásticas o distónicas, evitar cirugía correctora y mejorar la higiene y/o el vestido. La respuesta se evaluó con Escalas de Ashworth (EEA), Sindou-Millet (ESM) y OïBrien (EOB). Análisis estadístico.-Pruebas de rango de Wilcoxon y de signos, con p<0.05. Resultados.- La dosis por sesión fue de 3 a 10 U/kg, con mejoría de 2 grados en 8 pacientes según la EEA y un grado o más en el resto (p=0,004). En la ESM mejor- 60 por ciento en 2 pacientes , y 50 por ciento en los otros (p=0.006). La EOB mostró una buena correlación. La mejoría promedio fue 4.8 meses (4 a 10 m), facilitando la terapia física y ortesis. El efecto se relacionó con la dosis. Los efectos secundarios fueron: debilidad general, desequilibrio y hematoma focal. Conclusiones.- La NoTxBoA demostró efectividad y mínimos efectos colaterales en el tratamiento de espasticidad y distonía en la PCI como un manejo aditivo a las medidas de rehabilitación.

Neuropatía diabética. Parte 2 patología, procedimientos diagnósticos, prevención y tratamiento / Diabetic neuropathy. Part 2 pathology, diagnostic procedures, prevention, and treatment

Se analizaron cambios degenerativos en los nervios periféricos de pacientes diabéticos, a través de la clínica y de la investigación experimental. Los hallazgos histopatológicos incluyeron degeneración axonal y desmielinización segmentaria. Los cambios axonales involucraron pérdida de fibras de nervios mielinizados y no mielinizados de pequeño y gran calibre del ganglio de la raíz dorsal y de las células del asta anterior; degeneración de las columnas dorsales, desmielinización y remielinización de los nervios periféricos y, atrofia de las fibras musculares. Los estudios neurofisiológicos permitieron confirmar las alteraciones funcionales del sistema nervioso periférico afectado por la neuropatía diabética, cuyo tratamiento fundamental es el control de la glucemia, pudiendo -al lograr la normoglucemia- detener la progresión de ésta. Así mismo, la hiperglucemia se asocia con un menor umbral al dolor en pacientes con diabetes mellitus. Aparte de las medidas propias para lograr un buen control, han surgido varios medicamentos en las últimas décadas a partir de los posibles mecanismos fisiopatológicos como los inhibidores de la aldosa reductasa. En la mayoría de los casos el tratamiento es poco satisfactorio: se dirige a mejorar la función nerviosa o aliviar los síntomas que incluyen dolor y parestesias. El manejo sintomático de la neuropatía diabética dolorosa es fundamentalmente con antidepresivos tricíclicos, anticonvulsivos (fenitoína, carbamacepina y recientemente la gabapentina, xilocaína, mexiletina y capsaicina). Los tratamientos del ácido gamalinolénico, gangliósidos, ridina y el análogo de la corticotropina están en proceso para demostrar su potencial utilidad y mejorar la función neurológica; además de manejo de la neuropatía autonómica, medidas profilácticas de las extremidades, rehabilitación física, prótesis y cirugía.

Neuropatía diabética: clasificación fisiopatología y manifestaciones clínicas. Parte 1 / Diabetic neuropathy classification, physiopathology and clinical manifestations. Part 1

La neuropatía diabética constituye un grupo de trastornos de los nervios sensitivos, motores y del sistema nervioso autónomo provocado por diabetes mellitus, de la cual representa la complicación tardía más frecuente. Afecta a uno o varios nervios, plexos y raíces nerviosas; puede ser de presentación súbita o paulatina, resolverse de forma rápida o tener curso crónico, insidioso y progresivo. Las manifestaciones son variadas: van desde aquéllas prácticamente inexistentes hasta las que dan lugar a alteraciones funcionales y cuadros clínicos severos. Aproximadamente 15 por ciento de los pacientes diabéticos tiene al momento del diagnóstico tanto síntomas como signos de neuropatía, y 50 por ciento presenta anormalidades en los estudios neurofisiológicos. En la neuropatía diabética intervienen dos mecanismos fisiopatológicos: uno metabólico que afecta los nodos de Ranvier, las células de Schwann (productoras de mielina), o los axones; otro se refiere a la hiperglucemia que daña la microvasculatura endoneural. Entre los mecanismos metabólicos mejor reconocidos están el aumento de sorbitol en las células nerviosas, disminución de mioinositol libre en el nervio, menor actividad de la ATPasa de sodio-potasio en el nervio y mayor glucosilación no enzimática en el nervio periférico. Existen factores menos conocidos, como los factores neurotróficos. Por otro lado, en algunos pacientes con neuropatía diabética proximal parece ser que las características de las lesiones son de tipo inflamatorio (vasculitis inmune), que induce degeneración e isquemia de las fibras nerviosas. Otras formas frecuentes de neuropatía son las relacionadas con atrapamiento nervioso como el síndrome del túnel del carpo.