Variante juvenil de la enfermedad de Sandhoff: presentación del primer caso descrito en Argentina / Juvenile form of Sandhoff disease: first case reported in Argentina

La enfermedad de Sandhoff es una patología neurodegenerativa, de almacenamiento lisosomal, causada por mutaciones en el gen HEXB. Existen tres formas clínicas: infantil, juvenil y adulta. Previamente, fue identificada una población endogámica en la provincia de Córdoba, Argentina, que presentaba una alta incidencia de la enfermedad; todos los casos correspondieron a la forma infantil. En este trabajo, se presenta por primera vez el caso de un paciente argentino con la variante juvenil de la enfermedad de Sandhoff. El paciente es un niño de 7 años que, a partir de los 2, presentó ataxia, trastorno del habla y retraso global en el desarrollo. El diagnóstico se confirmó con la detección de valores residuales de enzima hexosaminidasa y con la identificación de dos mutaciones ya descritas en estado de heterocigosis: c.796T>G (p.Y266D) y c.1615C>T (p.R539C).

Sandhoff disease is a neurodegenerative, lysosomal and autosomal recessive disease caused by mutations in the HEXB gene. Three forms are recognized: infantile, juvenile and adult. Previously, an endogamous population in Córdoba, Argentina, was identified with a high incidence of Sandhoff disease, all reported cases were of the infantile type. In this work, we describe a child with the juvenile form of Sandhoff disease, the first case reported in Argentina. The patient is a 7-year-old boy presenting with ataxia, speech disturbances and global developmental delay, symptoms starting at the age of 2 years. Diagnosis was based on the hexosaminidase deficiency. Sequencing of genomic DNA revealed compound heterozygosity for two HEXB gene mutations: c.796T>G (p.Y266D) and c.1615C>T (p.R539C), both already reported.

A Case Refort of Sandhoff Disease

Sandhoff disease is a rare autosomal recessive metabolic disease presenting bilateral optic atrophy and a cherry red spot in the macula. This case report presents the characteristics of a patient with Sandhoff disease as assessed by ophthalmic, neuroimaging, and laboratory procedures. Ophthalmologic examination revealed that the patient could not fixate her eyes on objects nor follow moving targets. A pale optic disc and a cherry red spot in the macula were seen in both eyes. Low signal intensity at the thalamus and high signal intensity at the cerebral white matter were noted in a T2-weighted brain MR image. A lysosomal enzyme assay using fibroblasts showed the marked reduction of both total beta-hexosaminidases, A and B. Based on the above clinical manifestations and laboratory findings, we diagnosed the patient as having Sandhoff disease.

Doença de Sandhoff / Disease Sandhoff

Objetivo: Apresentar um caso raro de Doença de Sandhoff em criança de meses de idade. Local: Hospital Guilherme Álvaro, Santos - São Paulo. Método: Diagnosticado pelo Fundo de Olho pela "Mácula em Cereja" e pedido enzimas para diferenciar da Doença de tay-Sachs e estudo multiclínico pela Neuropediatria e Pediatria. Resultado: A associação dos achados fundoscópicos, clínicos e das enzimas hexosamidases A e B direcionaram para o diagnóstico. Conclusão: O exame acurado do Fundo de Olho foi direcionador diagnóstico da Doença de Sandhoff.

GM2 gangliosidoses: a review of cases confirmed by beta-N-acetylhexosaminidase assay.

The inborn errors of GM2 ganglioside metabolism cause GM2 ganglioside to accumulate within the lysosomes of the nerve cells. The majority of the patients are infants with the Tay-Sachs form of the disease associated with a severe deficiency of beta-N-Acetylhexosaminidase A (hexosaminidase A). Both Hexosaminidase A and B are deficient in Sandhoff disease. The serum total hexosaminidase and the percentage of hexosaminidase A and B were estimated in 449 patients who presented with progressive mental-motor retardation. Three cases of Tay-Sachs disease and two cases of Sandhoff disease were detected. They presented with exaggerated startle response to acoustic stimuli, seizures, optic atrophy and retinal cherry red spots in addition to psychomotor retardation. One case of Sandhoff disease had hepatosplenomegaly and skeletal deformities.

Enzyme studies in GM2 gangliosidiosis, and their application in prenatal diagnosis.

Assay of hexosaminidase A and B enzymes in four cases with developmental regression and cherry red spot on fundus examination confirmed that three cases had Tay-Sachs disease, and one case had Sandhoff disease. Prenatal diagnosis was carried out by hexosaminidase enzyme assay in amniotic fluid and cells in one family, and chorionic villus sample in the second family. The fetus was diagnosed to be unaffected in one, and affected in the other family. Assay of hexosaminidase A and B is useful for specific diagnosis of GM2 gangliosidosis, and for prenatal diagnosis to reduce the burden of these disorders.

Lysosomal storage disorders in Thailand: the Siriraj experience.

Lysosomal storage disorders are a heterogeneous group of biochemical genetic disorders; currently 40-50 are known. The clinical phenotype is determined by the tissue distribution of the storage material and degree of enzyme deficiency. The genetic transmission is mostly autosomal recessive. Lysosomal storage disorders can be divided into three groups according to the major organ system pathology: (1) Primary involvement of the central nervous system without significant somatic or skeletal pathology. Disorders of grey matter, eg gangliosidosis and disorders of white matter eg the leucodystrophy are the most common; (2) Primary involvement of the reticuloendothelial system with or without associated neuropathology, eg Niemann-Pick disease and Gaucher disease; (3) Multisystem involvement in which skeletal manifestations are prominent features. The mucopolysaccharidosis and mucolipidoses are the two major forms with this clinical phenotype. Lysosomal storage disorders identified at Siriraj Hospital are neuronal ceroid lipofuscinosis, GMI gangliosidosis, mucolipidosis II, Maroteaux-Lamy, sialidosis, Sly syndrome, Hunter syndrome, Morquio syndrome, Gaucher disease, Niemann-Pick, Sandhoff disease, Pompe's disease and many more. Most patients came from the provinces where consanguinity is common. Confirmation usually is done by enzyme assays using skin fibroblast culture or leucocytes. Genetic counseling is extremely important and prenatal diagnosis is recommended to high-risk couple.

Gangliosidosis GM2 tipo 2: enfermedad de Sandhoff / Gangliosidosis GM2 type 2: Sandhoff's disease

Se estudió a un niño de 19 meses de edad con un cuadro clínico sugestivo de gangliosidosis GM2: facies peculiar, retardo psicomotor severo, espasticidad generalizada, crisis convulsivas tónicas, macrocefalia, pérdida de la función visual y auditiva, reflejos osteotendinosos exaltados y primer dedo de ambos pies en flexión sostenida; manchas rojo cereza en fondo de ojo y atrofia cerebral demostrada por EEG y TAC. Mediante cromatografía de capa fina se identificaron oligosacáridos en diferentes muestras de orina con un patrón cromatográfico característico. La actividad de las hexosaminidasas A y B en el paciente y sus padre fueron compatibles con homocigocidad y heterocigocidad respectivamente, para la deficiencia de ambas enzimas. Estos resultados permitieron precisar el diagnóstico de gangliosidosis GM2 tipo 2 (Enfermedad de Sandhoff). Se señala la importancia de la identificación de la oligosacariduria