title: Clinical and biochemical study of 29 Brazilian patients with metachromatic leukodystrophy.
abstract: Metachromatic leukodystrophy (MLD) is a lysosomal disorder caused by arylsulfatase A (ARSA) deficiency. It is classified into three forms according to the age of onset of symptoms (late infantile, juvenile, and adult). We carried out a cross-sectional and retrospective study, which aimed to determine the epidemiological, clinical, and biochemical profile of MLD patients from a national reference center for Inborn Errors of Metabolism in Brazil. Twenty-nine patients (male, 17) agreed to participate in the study (late infantile form: 22; juvenile form: 4; adult form: 1; asymptomatic: 2). Mean ages at onset of symptoms and at biochemical diagnosis were, respectively, 19 and 39 months for late infantile form and 84.7 and 161.2 months for juvenile form. The most frequently reported first clinical symptom/sign of the disease was gait disturbance and other motor abnormalities (72.7%) for late infantile form and behavioral and cognitive alterations (50%) for juvenile form. Leukocyte ARSA activity level did not present significant correlation with the age of onset of symptoms (r = -0.09, p = 0.67). Occipital white matter and basal nuclei abnormalities were not found in patients with the late infantile MLD. Our results suggest that there is a considerable delay between the age of onset of signs and symptoms and the diagnosis of MLD in Brazil. Correlation between ARSA activity and MLD clinical form was not found. Further studies on the epidemiology and natural history of this disease with larger samples are needed, especially now when specific treatments should be available in the near future.
authors.affiliation: Medical Genetics Service, HCPA, Porto Alegre, RS, Brazil.
authors.forename: Osvaldo
authors.initials: O
authors.lastname: Artigalás
authors.forename: Valeska Lizzi
authors.initials: VL
authors.lastname: Lagranha
authors.forename: Maria Luiza
authors.initials: ML
authors.lastname: Saraiva-Pereira
authors.forename: Maira Graeff
authors.initials: MG
authors.lastname: Burin
authors.forename: Charles Marques
authors.initials: CM
authors.lastname: Lourenço
authors.forename: Hélio
authors.initials: H
authors.lastname: van der Linden
authors.forename: Mara Lúcia Ferreira
authors.initials: ML
authors.lastname: Santos
authors.forename: Sergio
authors.initials: S
authors.lastname: Rosemberg
authors.forename: Carlos Eduardo
authors.initials: CE
authors.lastname: Steiner
authors.forename: Fernando
authors.initials: F
authors.lastname: Kok
authors.forename: Carolina F Moura
authors.initials: CF
authors.lastname: de Souza
authors.forename: Laura B
authors.initials: LB
authors.lastname: Jardim
authors.forename: Roberto
authors.initials: R
authors.lastname: Giugliani
authors.forename: Ida Vanessa
authors.initials: IV
authors.lastname: Schwartz
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D015415:Biomarkers / Q000097:blood / Q000652:urine; D001938:Brazil / Q000453:epidemiology; D002553:Cerebroside-Sulfatase / Q000097:blood / Q000172:deficiency*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D003941:Diagnostic Techniques, Ophthalmological; D018450:Disease Progression; D004569:Electroencephalography; D005128:Eye Diseases / Q000175:diagnosis / Q000201:enzymology / Q000453:epidemiology; D005260:Female; D020233:Gait Disorders, Neurologic / Q000175:diagnosis / Q000201:enzymology / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007962:Leukocytes / Q000201:enzymology*; D007966:Leukodystrophy, Metachromatic / Q000175:diagnosis* / Q000188:drug therapy / Q000201:enzymology / Q000453:epidemiology; D056784:Leukoencephalopathies / Q000175:diagnosis / Q000201:enzymology / Q000453:epidemiology; D008279:Magnetic Resonance Imaging; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis / Q000201:enzymology / Q000453:epidemiology; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D013433:Sulfoglycosphingolipids / Q000652:urine; D013997:Time Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers; D013433:Sulfoglycosphingolipids; D002553:Cerebroside-Sulfatase