RESUMEN
Hypomyelinating leukodystrophies (HLDs) are a group of neurodevelopmental disorders that affect proper formation of the myelin sheath in the central nervous system. They are characterized by developmental delay, hypotonia, spasticity, and variable intellectual disability. In the past various classification systems for HLDs have been used, based on imaging findings, clinical manifestation, and organelle-specific disorders. Here we present a molecular insight into HLDs based on a defect in specific gene engaged in myelination. We discuss recent findings on pathogenesis, clinical presentation, and imaging related to these disorders. We focus on HLDs that are in use in differential diagnostics of Pelizaeus-Merzbacher disease (PMD), with a special emphasis on Allan-Herndon-Dudley syndrome (AHDS), an X-linked condition with delayed myelination due to thyroid transport disturbances. On the background of previously published patients we describe a proband initially considered as presenting with a severe PMD, whose diagnosis of AHDS due to a novel nonsense SLC16A2 mutation unraveled two previously undiagnosed generations of affected males who died in infancy from unexplained reasons. Since AHDS is found to be a relatively frequent cause of X-linked intellectual disability, we emphasize the need for determining the whole thyroid profile especially in hypotonic males with a delay of psychomotor development.
Asunto(s)
Leucoencefalopatías/genética , Discapacidad Intelectual Ligada al Cromosoma X/genética , Hipotonía Muscular/genética , Atrofia Muscular/genética , Enfermedad de Pelizaeus-Merzbacher/genética , Niño , Preescolar , Diagnóstico Diferencial , Genes Ligados a X , Humanos , Leucoencefalopatías/diagnóstico , Leucoencefalopatías/metabolismo , Masculino , Discapacidad Intelectual Ligada al Cromosoma X/diagnóstico , Discapacidad Intelectual Ligada al Cromosoma X/metabolismo , Hipotonía Muscular/diagnóstico , Hipotonía Muscular/metabolismo , Atrofia Muscular/diagnóstico , Atrofia Muscular/metabolismo , Mutación , Vaina de Mielina/genética , Vaina de Mielina/metabolismo , Linaje , Enfermedad de Pelizaeus-Merzbacher/diagnóstico , Enfermedad de Pelizaeus-Merzbacher/metabolismoRESUMEN
Large cell calcifying sertoli cell tumor (LCCSCT) is an exceptionally rare neoplasm originating from sperm cord cells. The tumors have relatively low malignant potential and unlikely proceed to metastasis formation. The lesions may occur in an isolated form or in ca. 40% of cases may be associated with genetic abnormalities, by and large Peutz-Jeghers syndrome and Carney complex. At presentation, 20% of LCCSCT cases are bilateral and/or multifocal. Owning to characteristic skin lesions and particular hyperechoic ultrasound image of the tumor, preliminary diagnosis of the syndromic LCCSCT is possible in the preoperative period. Consequently, testicle organ-sparing procedure can be attempted, which is especially justified in bilateral lesions. Here, we report a case of a bilateral LCCSCT in a 20-year-old man with atypical Peutz-Jeghers syndrome due to amplification of the exon 1 of STK11 gene who was successfully treated with bilateral testicle-sparing tumorectomies.