ABSTRACT
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.
ABSTRACT
Pompe disease (glycogen storage disease type II) is an autosomal recessive disorder caused by deficiency of acid-alpha-glucosidase (GAA) resulting in lysosomal glycogen accumulation in multiple tissue, particularly cardiac and skeletal muscle. The classic infantile form of Pompe disease is characterized by marked cardiomegaly, respiratory failure and severe generalized hypotonia. Most patients die from cardiorespiratory failure or respiratory infection within the first year or two of life without treatment. A "non-classic" phenotype presents with less severe clinical feature and slow progression of disease. We report two patients with non-classic infantile Pompe disease from one family manifested hypertrophic cardiomyopathy and progressive proximal weakness.