Infantile-onset Pompe disease in seven Mexican children.

INTRODUCTION: Pompe disease (PD) is a rare form of metabolic myopathy; the classic infantile presentation is severe, with death occurring before reaching one year of life, and the non-classical form is of slower progression and survival can exceed one year. OBJECTIVE: To describe the genotype and characteristics of Mexican patients with infantile-onset PD. METHODS: Seven patients with PD confirmed by enzymatic activity determination and GAA gene molecular analysis were included. Mutations were reviewed in genomic databases. RESULTS: Median age at symptom onset was four months (1-12 months) and age at diagnosis was eight months (4-16 months). All patients had cardiomyopathy: four who died before one year of age had mutations that predicted severe disease (c.2431dup, c.2560C>T, c.655G>A, c.1987delC) and were negative for cross-reactive immunologic material (CRIM). Three patients survived after one year of age with enzyme replacement therapy; one survived almost five years, another 18 months, and one girl was almost three years of age at the time of this report; their pathogenic variants predicted potentially less severe disease (c.1979G>A, c.655G>A, c.1447G>A) and they were positive for CRIM. CONCLUSION: There was a good correlation between genotype and phenotype in children with Pompe disease.

INTRODUCCIÓN: La enfermedad de Pompe (EP) es una forma rara de miopatía metabólica; la presentación infantil clásica es severa y el fallecimiento acontece antes del año de vida, y la forma no clásica es de progresión más lenta y la sobrevivencia puede superar el año. OBJETIVO: Describir genotipo y características de pacientes mexicanos con EP de inicio infantil. MÉTODOS: Se incluyeron siete pacientes con enfermedad confirmada mediante actividad enzimática y estudio molecular del gen GAA. Se revisaron las mutaciones en bases de datos genómicas. RESULTADOS: La mediana de la edad de inicio de los síntomas fue de cuatro meses (1-12 meses) y la edad de diagnóstico fue de ocho meses (4-16 meses). Todos los pacientes tenían cardiomiopatía: cuatro que fallecieron antes del año presentaron mutaciones que predicen enfermedad severa (c.2431dup, c.2560C>T, c.655G>A, c.1987delC) y CRIM (cross-reactive immunologic material) negativo; tres sobrevivieron después del año de edad con terapia de reemplazo enzimático, uno casi cinco años, otro 18 meses y una niña tenía casi tres años al momento de este informe; sus variantes patogénicas predecían enfermedad potencialmente menos severa (c.1979G>A, c.655G>A, c.1447G>A) y CRIM positivo. CONCLUSIÓN: Existió buena correlación entre genotipo y fenotipo en niños con enfermedad de Pompe.

Enfermedad de Pompe de inicio infantil en siete niños mexicanos / Infantile-onset Pompe disease in seven Mexican children

Resumen Introducción: La enfermedad de Pompe (EP) es una forma rara de miopatía metabólica; la presentación infantil clásica es severa y el fallecimiento acontece antes del año de vida, y la forma no clásica es de progresión más lenta y la sobrevivencia puede superar el año. Objetivo: Describir genotipo y características de pacientes mexicanos con EP de inicio infantil. Métodos: Se incluyeron siete pacientes con enfermedad confirmada mediante actividad enzimática y estudio molecular del gen GAA. Se revisaron las mutaciones en bases de datos genómicas. Resultados: La mediana de la edad de inicio de los síntomas fue de cuatro meses (1-12 meses) y la edad de diagnóstico fue de ocho meses (4-16 meses). Todos los pacientes tenían cardiomiopatía: cuatro que fallecieron antes del año presentaron mutaciones que predicen enfermedad severa (c.2431dup, c.2560C>T, c.655G>A, c.1987delC) y CRIM (cross-reactive immunologic material) negativo; tres sobrevivieron después del año de edad con terapia de reemplazo enzimático, uno casi cinco años, otro 18 meses y una niña tenía casi tres años al momento de este informe; sus variantes patogénicas predecían enfermedad potencialmente menos severa (c.1979G>A, c.655G>A, c.1447G>A) y CRIM positivo. Conclusión: Existió buena correlación entre genotipo y fenotipo en niños con enfermedad de Pompe.

Abstract Introduction: Pompe disease (PD) is a rare form of metabolic myopathy; the classic infantile presentation is severe, with death occurring before reaching one year of life, and the non-classical form is of slower progression and survival can exceed one year. Objective: To describe the genotype and characteristics of Mexican patients with infantile-onset PD. Methods: Seven patients with PD confirmed by enzymatic activity determination and GAA gene molecular analysis were included. Mutations were reviewed in genomic databases. Results: Median age at symptom onset was four months (1-12 months) and age at diagnosis was eight months (4-16 months). All patients had cardiomyopathy: four who died before one year of age had mutations that predicted severe disease (c.2431dup, c.2560C>T, c.655G>A, c.1987delC) and were negative for cross-reactive immunologic material (CRIM). Three patients survived after one year of age with enzyme replacement therapy; one survived almost five years, another 18 months, and one girl was almost three years of age at the time of this report; their pathogenic variants predicted potentially less severe disease (c.1979G>A, c.655G>A, c.1447G>A) and they were positive for CRIM. Conclusion: There was a good correlation between genotype and phenotype in children with Pompe disease.

Mutations Related to Antiretroviral Resistance Identified by Ultra-Deep Sequencing in HIV-1 Infected Children under Structured Interruptions of HAART.

Although Structured Treatment Interruptions (STI) are currently not considered an alternative strategy for antiretroviral treatment, their true benefits and limitations have not been fully established. Some studies suggest the possibility of improving the quality of life of patients with this strategy; however, the information that has been obtained corresponds mostly to studies conducted in adults, with a lack of knowledge about its impact on children. Furthermore, mutations associated with antiretroviral resistance could be selected due to sub-therapeutic levels of HAART at each interruption period. Genotyping methods to determine the resistance profiles of the infecting viruses have become increasingly important for the management of patients under STI, thus low-abundance antiretroviral drug-resistant mutations (DRM's) at levels under limit of detection of conventional genotyping (<20% of quasispecies) could increase the risk of virologic failure. In this work, we analyzed the protease and reverse transcriptase regions of the pol gene by ultra-deep sequencing in pediatric patients under STI with the aim of determining the presence of high- and low-abundance DRM's in the viral rebounds generated by the STI. High-abundance mutations in protease and high- and low-abundance mutations in reverse transcriptase were detected but no one of these are directly associated with resistance to antiretroviral drugs. The results could suggest that the evaluated STI program is virologically safe, but strict and carefully planned studies, with greater numbers of patients and interruption/restart cycles, are still needed to evaluate the selection of DRM's during STI.