<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>1665-1146</journal-id>
<journal-title><![CDATA[Boletín médico del Hospital Infantil de México]]></journal-title>
<abbrev-journal-title><![CDATA[Bol. Med. Hosp. Infant. Mex.]]></abbrev-journal-title>
<issn>1665-1146</issn>
<publisher>
<publisher-name><![CDATA[Instituto Nacional de Salud, Hospital Infantil de México Federico Gómez]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1665-11462023000700047</article-id>
<article-id pub-id-type="doi">10.24875/bmhim.22000100</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Heterogeneidad clínica y molecular en los trastornos asociados con CDKL5]]></article-title>
<article-title xml:lang="en"><![CDATA[Clinical and molecular heterogeneity in CDLK5 disorders]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Vázquez-Montante]]></surname>
<given-names><![CDATA[José J.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Márquez-Rojo]]></surname>
<given-names><![CDATA[Paola]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Saavedra-Milán]]></surname>
<given-names><![CDATA[Berenice]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Hernández-Medrano]]></surname>
<given-names><![CDATA[Cristina]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Bravo-Oro]]></surname>
<given-names><![CDATA[Antonio]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Hospital Central Dr. Ignacio Morones Prieto Departamento de Genética Médica ]]></institution>
<addr-line><![CDATA[San Luis Potosí ]]></addr-line>
<country>México</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Hospital Central Dr. Ignacio Morones Prieto División de Pediatría Departamento de Neurología Pediátrica]]></institution>
<addr-line><![CDATA[San Luis Potosí ]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2023</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2023</year>
</pub-date>
<volume>80</volume>
<fpage>47</fpage>
<lpage>52</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1665-11462023000700047&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1665-11462023000700047&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1665-11462023000700047&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen  Introducción: El síndrome por deficiencia de CDKL5 es originado por variantes patogénicas en el gen CDKL5, con un espectro clínico variable que va desde pacientes con características del trastorno del espectro autista hasta epilepsia de inicio temprano y refractaria al tratamiento. Inicialmente fue considerado como una forma atípica de síndrome de Rett.  Casos clínicos: Presentamos tres pacientes no relacionadas, evaluadas por retraso global del desarrollo y epilepsia refractaria. Los tres casos eran hemicigotos a una variante patógena de CDKL5. En una paciente se realizó panel de 306 genes asociados con epilepsia; en las otras dos se realizó microarreglo genómico comparativo. Las características clínicas y los hallazgos en el electroencefalograma y la resonancia magnética cerebral se han descrito clásicamente en el espectro de manifestaciones de este síndrome.  Conclusiones: El síndrome por deficiencia de CDKL5 representa un reto para los médicos, ya que en muchos casos las manifestaciones clínicas y los estudios electroencefalográficos y de neuroimagen pueden ser inespecíficos. Debe sospecharse este síndrome ante la presencia de retraso global del desarrollo, fenotipo conductual autista y epilepsia, asociado o no con dismorfias. Dada la similitud entre diversas encefalopatías epilépticas, se deben solicitar paneles multigénicos que incluyan la secuenciación y el análisis de duplicación/deleción en los que se contemple este gen y sus posibles diagnósticos diferenciales, aunque sin olvidar la utilidad de las técnicas genómicas en casos poco claros.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract  Background: CDKL5 deficiency syndrome is caused by pathogenic variants in the CDKL5 gene, with a variable clinical spectrum ranging from patients with characteristics of autism spectrum disorder to early-onset epilepsy refractory to treatment. Initially, until the gene was discovered, it was considered an atypical form of Rett syndrome. This study aimed to describe the clinical and molecular heterogeneity in CDLK5 disorders among three female patients with CDKL5 pathogenic variants.  Case reports: We reported three unrelated Mexican female patients evaluated for global developmental delay and epilepsy. All three cases were hemizygotes to a CDKL5 pathogenic variant. In one patient, we performed a 306 gene panel associated with epilepsy. In the other two cases, a human genomic microarray was performed. We describe their clinical features electroencephalogram and brain magnetic resonance evaluations.  Conclusions: CDKL5 deficiency syndrome represents a challenge for clinicians since the clinical manifestations, electroencephalographic and neuroimaging studies can be non-specific. This syndrome should be suspected in the presence of global developmental delay, autistic behavioral phenotype and epilepsy, associated or not with dysmorphia. Given the similarity between various epileptic encephalopathies, multigene panels including sequencing and duplication/deletion analysis should be requested in which this gene and its possible differential diagnoses are considered, without forgetting the usefulness of genomic techniques in unclear cases.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[CDKL5]]></kwd>
<kwd lng="es"><![CDATA[Trastorno por deficiencia de CDKL5]]></kwd>
<kwd lng="es"><![CDATA[Encefalopatía epiléptica temprana]]></kwd>
<kwd lng="es"><![CDATA[Retraso global del neurodesarrollo]]></kwd>
<kwd lng="es"><![CDATA[Epilepsia refractaria]]></kwd>
<kwd lng="en"><![CDATA[CDKL5]]></kwd>
<kwd lng="en"><![CDATA[CDKL5 deficiency disorder]]></kwd>
<kwd lng="en"><![CDATA[Epileptic encephalopathy]]></kwd>
<kwd lng="en"><![CDATA[Developmental delay]]></kwd>
<kwd lng="en"><![CDATA[Drug resistant epilepsy]]></kwd>
</kwd-group>
</article-meta>
</front><back>
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