RESUMEN
Congenital disorders of glycosylation (CDG) are recessively inherited multisystemic disorders resulting from several genetic defects affecting the assembly, transfer or processing of oligosaccharides onto proteins and other glycoconjugates. CDG type Ib is due to a deficiency of phosphomannose isomerase (PMI) encoded by the MPI gene. PMI catalyzes the interconversion of fructose-6-P and mannose-6-P. The clinical phenotype is characterized by gastro-intestinal and hepatic symptoms. In contrast to most CDG patients, there is no neurological affectation. It's a mannose treatable disorder. We report the first recognised case of CDG Ib in Spain. He presented at 6 months with hypoglycaemia, failure to thrive and hypertransaminasaemia. He subsequently developed an enteropathy with subtotal villous atrophy on biopsy. The %CDT was very high and he presented with a type 1 pattern in transferrin isoelectric focusing. PMI activity in fibroblasts was very deficient. Mutations in MPI gene at R219Q and R56fs were found. Clinical and biochemical parameters normalised after treatment with mannose 1 g/kg/day in 5 doses. CDG Ib should be considered in patients with hypoglycaemia, liver disease, enteropathy and hypercoagulability, in the absence of other common causes, and particularly if some of them are combined.
Asunto(s)
Glicosilación , Manosa/uso terapéutico , Errores Innatos del Metabolismo/clasificación , Errores Innatos del Metabolismo/tratamiento farmacológico , Preescolar , Humanos , Lactante , MasculinoRESUMEN
Los defectos congénitos de la glucosilación (CDG, por sus siglas en inglés) son enfermedades genéticas, en general multisistémicas, de herencia autosómica recesiva. Son causadas por defectos que afectan al ensamblaje, la transferencia o el procesamiento de los oligosacáridos de las proteínas u otros glucoconjugados. El CDG tipo Ib está causado por la deficiencia de la enzima citosólica fosfomanosa isomerasa (PMI), codificada por el gen MPI, que cataliza la interconversión de fructosa-6-P y manosa-6-P. Los síntomas son, fundamentalmente, gastrointestinales y hepáticos, y a diferencia de la mayoría de los pacientes con otros tipos de defectos congénitos de la glucosilación, no existe afectación neurológica. El tratamiento con manosa es muy eficaz. Describimos el primer caso de un paciente con CDG-Ib diagnosticado en España. La enfermedad se inició clínicamente a los 6 meses con hipoglucemia, fallo de medro e hipertransaminasemia; posteriormente el paciente desarrolló una enteropatía con atrofia vellositaria subtotal detectada en la biopsia. El paciente presentaba un porcentaje de transferrina deficiente en carbohidratos en el suero del 42 %, un patrón tipo 1 en el isoelectroenfoque de la transferrina sérica, una actividad PMI en fibroblastos del 16 % y las mutaciones R219Q y R56fs en el gen MPI. El tratamiento con manosa a dosis de 1 g/kg/día en 5 dosis resultó muy eficaz, y se normalizaron tanto los parámetros clínicos como los bioquímicos. El defecto congénito de la glucosilación Ib debería incluirse en el diagnóstico diferencial de hipoglucemias, hepatopatías, enteropatías y situaciones de hipercoagulabilidad, en ausencia de otras etiologías más comunes y, sobre todo, si se asocian varios de estos síntomas (AU)
Congenital disorders of glycosylation (CDG) are recessively inherited multisystemic disorders resulting from several genetic defects affecting the assembly, transfer or processing of oligosaccharides onto proteins and other glycoconjugates. CDG type Ib is due to a deficiency of phosphomannose isomerase (PMI) encoded by the MPI gene. PMI catalyzes the interconversion of fructose-6-P and mannose-6-P. The clinical phenotype is characterized by gastro-intestinal and hepatic symptoms. In contrast to most CDG patients, there is no neurological affectation. It's a mannose treatable disorder. We report the first recognised case of CDG Ib in Spain. He presented at 6 months with hypoglycaemia, failure to thrive and hypertransaminasaemia. He subsequently developed an enteropathy with subtotal villous atrophy on biopsy. The % CDT was very high and he presented with a type 1 pattern in transferrin isoelectric focusing. PMI activity in fibroblasts was very deficient. Mutations in MPI gene at R219Q and R56fs were found. Clinical and biochemical parameters normalised after treatment with mannose 1 g/kg/day in 5 doses. CDG Ib should be considered in patients with hypoglycaemia, liver disease, enteropathy and hypercoagulability, in the absence of other common causes, and particularly if some of them are combined (AU)
Asunto(s)
Humanos , Masculino , Recién Nacido , Glicosilación , Manosa/uso terapéutico , Errores Congénitos del Metabolismo Esteroideo/complicaciones , Errores Congénitos del Metabolismo Esteroideo/diagnóstico , Diagnóstico Diferencial , Hipoglucemia/diagnóstico , Hipoglucemia/terapia , Bromocriptina/uso terapéutico , Desnutrición/complicaciones , Manosa-6-Fosfato Isomerasa/deficiencia , Hipoglucemia/complicaciones , Biomarcadores/análisis , Hipoglucemia/congénito , Enfermedad Celíaca/complicaciones , Deficiencia de Proteína/complicacionesRESUMEN
A new patient with neonatal lactic acidosis due to pyruvate carboxylase deficiency is described. Since birth he developed vomiting, hypothermia, lethargy, irritability, hypoglycemia and severe metabolic acidosis. During admission a progressive deterioration was observed. Despite different attempted therapies patient died at 4 1/2 months of age. High levels of plasma and urine lactate and pyruvate were detected. Enzymatic studies in cultures skin fibroblasts and postmortem tissues showed a severe deficiency of pyruvate carboxylase.