Metachromatic leukodystrophy (MLD) is an inherited disease caused by a deficiency of the enzyme arylsulfatase A (ARSA). Lentivirus-modified autologous hematopoietic stem cell gene therapy (HSCGT) has recently been approved for clinical use in pre and early symptomatic children with MLD to increase ARSA activity. Unfortunately, this advanced therapy is not available for most patients with MLD who have progressed to more advanced symptomatic stages at diagnosis. Patients with late-onset juvenile MLD typically present with a slower neurological progression of symptoms and represent a significant burden to the economy and healthcare system, whereas those with early onset infantile MLD die within a few years of symptom onset. We conducted a pilot study to determine the safety and benefit of HSCGT in patients with postsymptomatic juvenile MLD and report preliminary results. The safety profile of HSCGT was favorable in this long-term follow-up over 9 years. The most common adverse events (AEs) within 2 months of HSCGT were related to busulfan conditioning, and all AEs resolved. No HSCGT-related AEs and no evidence of distorted hematopoietic differentiation during long-term follow-up for up to 9.6 years. Importantly, to date, patients have maintained remarkably improved ARSA activity with a stable disease state, including increased Functional Independence Measure (FIM) score and decreased magnetic resonance imaging (MRI) lesion score. This long-term follow-up pilot study suggests that HSCGT is safe and provides clinical benefit to patients with postsymptomatic juvenile MLD.
Humans ; Leukodystrophy, Metachromatic/genetics* ; Pilot Projects ; Genetic Therapy/methods* ; Hematopoietic Stem Cell Transplantation ; Male ; Follow-Up Studies ; Female ; Lentivirus/genetics* ; Child ; Child, Preschool ; Hematopoietic Stem Cells/metabolism* ; Cerebroside-Sulfatase/metabolism* ; Adolescent

OBJECTIVE: To explore the genetic basis for a Chinese patient suspected for Canavan disease. METHODS: Whole exome sequencing (WES) was carried out for the proband, and candidate variants were verified by Sanger sequencing of the proband, her parents and brother. Prenatal diagnosis was provided to her mother by chorionic villi sampling (CVS) upon her subsequent pregnancy. RESULTS: The proband, a 4-month-old female infant, had manifested drowsiness, hypotonia and apathy. Urine metabolism screening showed elevated N-acetylaspartic acid. Cranial magnetic resonance imaging revealed abnormal myelination and multiple abnormal signals in large brain areas. WES revealed that the proband has harbored compound heterozygous variants of the ASPA gene, namely c.187A>G (p.Arg63Gly) in exon 1 and c.634+1G>A (P.?) in exon 4. Sanger sequencing confirmed that the c.187A>G (p.Arg63Gly) and c.634+1G>A (p.?) variants were respectively inherited from her mother and father. Her phenotypically normal brother has carried a heterozygous c.634+1G>A (p.?) variant. Prenatal diagnosis by CVS indicated that the fetus was a heterozygous carrier of the c.187A>G variant. CONCLUSION WES can facilitate the diagnosis of Canavan disease, particularly for those lacking specific phenotypes of the disease. The compound heterozygous variants of the ASPA gene probably underlay the Canavan disease in this patient, and the result has enabled prenatal diagnosis for this family.
Canavan Disease/genetics* ; China ; Female ; Humans ; Male ; Mutation ; Pedigree ; Pregnancy ; Prenatal Diagnosis

OBJECTIVE: To explore the genetic basis for a child with metachromatic leukodystrophy (MLD). METHODS: Clinical data of the patient was collected. Genomic DNA was extracted from peripheral blood samples of the child and his family members. Potential variant was screened by whole exome sequencing (WES), and candidate variant was verified by Sanger sequencing. The pathogenicity the variant was analyzed by multiple sequence alignment of the amino acid sequence and three-dimensional model prediction of its protein product. RESULTS: The child was found to harbor compound heterozygous variants c.257G>A (p.R86Q) and c.467del (p.G156Afs*6) of the ARSA gene, among which the c.467del (p.G156Afs*6) frameshift variation was unreported previously. Multiple sequence alignment showed that the site of the c.257G>A (p.R86Q) missense variant is highly conserved. Three-dimensional structure modeling analysis showed that the partial deletion due to the p.G156Afs*6 variant may cause significant alteration of the structure of ARSA protein. CONCLUSION The discovery of novel variant in ARSA has enriched the mutational spectrum of MLD and may facilitate the understanding of the genotype-phenotype correlation of MLD.
Cerebroside-Sulfatase/genetics* ; DNA ; Genetic Association Studies ; Humans ; Leukodystrophy, Metachromatic/genetics* ; Mutation

OBJECTIVE: To explore the clinical features and genetic variant in a child featuring megalencephalic leukoencephalopathy with subcortical cyst (MLC) type 2B. METHODS: Clinical and imaging data of the child was collected. Potential variant of hepatocyte adhesion molecule (HEPACAM) gene was detected by Sanger sequencing. The growth and development of her mother and uncle was also reviewed. RESULTS: The patient, a 1-year-and-7-month female, presented with convulsion, mental retardation and abnormally increased head circumference. Cranial MRI revealed extensive long T1 long T2 signals in the white matter of bilateral cerebral hemisphere, right anterior sac cyst, cerebral gyrus widening, and shallow sulcus. Sanger sequencing identified a c.437C>T missense variant in exon 3 of the HEPACAM gene. The same variant was detected in her mother but not father. Her mother and maternal uncle both had a history of increased head circumference when they were young. In their adulthood, the head circumference was in the normal range but still greater than the average. CONCLUSION The heterozygous variant of the HEPACAM gene probably underlies the MLC2B in this child. The variant has derived from her asymptomatic mother, which suggested incomplete penetrance of the MLC2B.
Adult ; Cell Cycle Proteins ; genetics ; Cerebrum ; diagnostic imaging ; Cysts ; diagnostic imaging ; genetics ; Female ; Genetic Variation ; Hereditary Central Nervous System Demyelinating Diseases ; diagnostic imaging ; genetics ; Humans ; Infant

Pelizaeus-Merzbacher disease (PMD) is a progressive and degenerative chromosomal disorder of the central nervous system caused by defective myelin production. Few case reports have been issued on the anesthetic management of PMD, because of its extremely low incidence. We anesthetized a 13-year-old female patient diagnosed with PMD for ophthalmic surgery because of intermittent exotropia. General anesthesia was induced and maintained with propofol and sevoflurane in air and oxygen. Rocuronium was administered to facilitate orotracheal intubation, and residual neuromuscular blockage was reversed with pyridostigmine. Between emergence to 24 hours postoperatively, her muscle power completely recovered and no unpredictable events occurred. Summarizing, anesthesiologists should be concerned about the high possibility of aspiration, spasticity, and seizure during the perioperative period in patients with even mild PMD. Appropriate preoperative evaluation, intraoperative monitoring, and choice of proper anesthetic drugs enable safe anesthesia in patients with PMD.
Adolescent* ; Anesthesia ; Anesthesia, General* ; Anesthetics ; Central Nervous System ; Chromosome Disorders ; Exotropia ; Female ; Humans ; Incidence ; Intubation ; Monitoring, Intraoperative ; Muscle Spasticity ; Myelin Sheath ; Oxygen ; Pelizaeus-Merzbacher Disease* ; Perioperative Period ; Propofol ; Pyridostigmine Bromide ; Seizures

OBJECTIVE: To explore the clinical, electrophysiological and imaging features of a patient with Krabbe disease caused by GALC mutation. METHODS: A comprehensive analysis including clinical investigation and genetic testing was carried out. RESULTS: The patient presented with peripheral neuropathy with electrophysiological anomaly suggestive of asymmetric demyelinating neuropathy. Brain imaging revealed leukoencephalopathy. Genetic analysis has identified compound heterozygous mutations in exons 5 and 11 of the GALC gene, namely c.461C>A and c.1244G>A. CONCLUSION Krabbe disease is a group of disorders featuring substantial phenotypic heterogeneity. Genetic and enzyme testing has become indispensable for accurate diagnosis for this disease.
DNA Mutational Analysis ; Galactosylceramidase ; genetics ; Genetic Testing ; Humans ; Leukodystrophy, Globoid Cell ; complications ; genetics ; Mutation ; Peripheral Nervous System Diseases ; etiology

Globoid cell leukodystrophy is a rare autosomal recessive disorder of the brain white-matter caused by galactosylceramidase deficiency; the disorder is classified into four types based on the age of onset. Approximately 80–85% of patients have an early infantile form, while 10–15% has a late infantile form. Globoid cell leukodystrophy leads to a progressive neurological deterioration, and affected patients rarely survive more than 2–3 years. Although many different treatments have been investigated over several decades, further research is still needed. Hematopoietic stem cell transplantation is the standard treatment for globoid cell leukodystrophy. Here, we report a case of symptomatic late-infantile globoid cell leukodystrophy treated with stem cell transplantation. After transplantation, disease progression ceased and cognitive and motor function improved. And a 6 months follow-up study using brain magnetic resonance imaging showed white matter involvement was increased. After that, annual follow-up brain magnetic resonance imaging showed a stable status of disease.
Age of Onset ; Brain ; Disease Progression ; Follow-Up Studies ; Galactosylceramidase ; Hematopoietic Stem Cell Transplantation* ; Hematopoietic Stem Cells* ; Humans ; Leukodystrophy, Globoid Cell* ; Magnetic Resonance Imaging ; Stem Cell Transplantation ; White Matter

Metachromatic leukodystrophy is an inherited lysosomal storage disorder caused by the deficiency of arylsulfatase A activity. The patient in this study, a 5-yr-old girl, presented with progressive psychomotor regression. An MRI image of her brain showed bilateral symmetrical demyelination. The arylsulfatase A activity in her leukocytes was decreased to 8.0 nmol/hr/mg protein (reference range, 25-80 nmol/hr/mg protein). Mutation analysis of ARSA, using PCR and direct sequencing, showed two heterozygote pathogenic variations of c.449C>T (p.Pro150Leu) and c.640G>A (p.Ala214Thr). In summary, we report a Korean patient with an early juvenile form of metachromatic leukodystrophy, who was diagnosed based on her clinical symptoms as well as by using biochemical, radiological, and molecular genetic investigations.
Brain ; Cerebroside-Sulfatase ; Demyelinating Diseases ; Female ; Heterozygote ; Humans ; Leukocytes ; Leukodystrophy, Metachromatic* ; Magnetic Resonance Imaging ; Molecular Biology* ; Polymerase Chain Reaction

No abstract available.
Alexander Disease* ; Diffusion*

OBJECTIVETo detect potential mutation of MLC1 gene in a child affected with megalencephalic leukoencephalopathy with subcortical cysts (MLC).

METHODSClinical symptoms of the patient were retrieved. Peripheral blood DNA samples from the patient, her parents and healthy controls were collected. Potential mutation of the MLC1 gene was detected by polymerase chain reaction and Sanger sequencing.

RESULTSThe patient presented with severe motor developmental delay and a giant skull. Magnetic resonance scan showed diffuse white matter swelling in bilateral hemispheres. DNA sequencing identified a novel homozygous c.177-c.180delC mutation of the MLC1 gene. The parents of the patient both carried a heterozygous mutation c.177-c.180delC but had a normal phenotype.

CONCLUSIONA novel MLC1 mutation c.177-c.180delC has been identified in a patient with MLC. The mutation is presumably disease-causing and has derived from parents who are both carriers.

Child, Preschool ; Cysts ; genetics ; Female ; Hereditary Central Nervous System Demyelinating Diseases ; genetics ; Humans ; Membrane Proteins ; genetics ; Mutation