Considerations for Familial Chylomicronemia Diagnosis in the Era of Next-Generation Sequencing: A Latin American Perspective

Abstract Familial chylomicronemia syndrome (FCS) is an autosomal recessive disorder, characterized by alterations in the catabolism of chylomicrons and by increased levels of plasma triglycerides. It has been shown that about 60-90% of FCS patients have biallelic mutations in the LPL gene and the remaining patients have mutations in genes encoding proteins closely related to LPL function. The objective of this manuscript is to illustrate the different clinical scenarios of FCS presentation, and to guide practitioners on the usefulness of genetic tests in each of them. To this end, several published papers about recommendations for the diagnosis of FCS are discussed briefly, in addition to the presentation of several hypothetical cases, highlighting different clinical presentations and possible associated genetic findings. These cases illustrate the multiplicity of potential aspects of family history, clinical manifestations, biochemical parameters, and patterns of genetic variants found in genomic analyses of FCS.

Hipoacusia de causa genética en cubanos con implante coclear / Hearing impairment of genetic origin in Cuban pat i ents with cochlear implant

Introducción: la hipoacusia neurosensorial es la forma más común de déficit auditivo. Presenta gran heterogeneidad clínica y etiológica; la frecuencia relativa de su causa varía de acuerdo con el método de estudio empleado. El implante coclear es el tratamiento más eficaz en la hipoacusia neurosensorial bilateral profunda.Objetivos: identificar las causas de la hipoacusia en pacientes cubanos con implante coclear y describir sus características clínicas. Material y Método: se realizó un estudio descriptivo transversal en el período septiembre de 2012 a diciembre de 2013. Se evaluaron clínicamente niños y adultos receptores de un implante coclear, implantados en Cuba hasta diciembre de 2012. Resultados: se identificó el origen genético en 33.8 por ciento de los implantados; distribuidos en sindrómicos y no sindrómicos, en proporciones similares; en 36.4 por ciento se atribuyó un factor ambiental al origen del déficit auditivo y en 29.8 por ciento no se logró identificar su causa. El inicio y evolución de la hipoacusia se correspondió con lo descrito para los distintos grupos etiológicos. Conclusiones: se evidenció la heterogeneidad clínica y etiológica de la hipoacusia neurosensorial en los implantados, cuya evaluación clínica es necesaria, no solo para proponer o descartar un origen genético, sino también para el asesoramiento de los pacientes y las familias(AU)

Introduction: neurosensory hearing loss is the most frequent auditory disability. It has great clinical and etiologic heterogeneity; its relative etiology frequency may vary depending upon the study method. Cochlear implantation is the most efficient treatment for bilateral and profound neurosensory hearing loss. Objectives: to identify causes of Neurosensory hearing lost in Cuban patients with Cochlear implantation and to describe its clinical features. Material and Methods: a transversal descriptive study was performed between September 2012 and December 2013. Children and adults with Cochlear implantation, implanted in Cuba until 2012 were clinically studied.Results: genetic origin was identified in 33.8 percent of the implanted patients; syndromic and nonsyndromic forms had similar proportions. In 36.4 percent an environmental factor was attributed to cause the hearing deficiency and in 29.8 percent the origin was not identified. The onset and evolution of the hearing loss behaved as described in different etiologic groups. Conclusion: clinical and etiological heterogeneity was evident among patients with Cochlear implantation; clinical assessment is necessary to establish genetic origin and provide genetic counseling to patients and their family(AU)