A 9-year-old girl with a phenotype similar to a mucopolysaccharidosis (MPS) and a clinical history characteristic of late infantile metachromatic leukodystrophy (MLD) is reported from the Department of Neurology, National Defense Medical Center, Taipei, Taiwan, Republic of China; the Developmental and Metabolic Neurology Branch, NIH, Bethesda, Maryland; and Department of Pediatrics (Dr. Horwitz), University of Chicago, Chicago, Illinois. The girl's early history and development were normal up to 18 months of age. Following a high fever with a flu-like illness, her gait became unsteady and broad- based. Gradually her speech became slurred and her vocabulary deteriorated. Examination at 7 1/2 years showed short stature and microcephaly. She was autistic and inattentive, with marked cognitive impairment. She had hyperreflexia, extensor plantar responses, dysmetria, and incoordination. Dysmorphic features suggested MPS but dysostosis multiplex and organomegaly were absent. Funduscopic examination revealed a cherry-red-like spot and yellowish-granular appearance of the retina. Deficient activities of arylsulfatase-A, arylsulfatase-B, iduronate sulfatase, and heparan N-sulfatase in the leukocytes established the diagnosis as MSD. The total urinary content of the glycosaminoglycans was normal, but the concentration of heparan sulfate was increased, stressing the need for qualitative estimations when MSD is suspected. [1]

COMMENT. Multiple sulfatase deficiency or mucosulfatidosis (MSD) is an autosomal recessive genetic disease affecting the expression of lysosomal sulfatases with consequent accumulation of sulfate-containing glycolipids, glycosaminoglycans, and steroid sulfates in tissues and body tissues. The clinical manifestations represent a combination of 2 diseases: late infantile MLD and MPS. The disorder is rare and the authors cite 20 previous reports of this phenotype.