Neurologic manifestations in mucopolysaccharidoses

Mucopolysaccharidoses (MPS) are progressive multisystem lysosomal storage diseases caused by defective catabolism of complex molecules, namely the glycosaminoglycans and their consequent accumulation in tissues. Of the 7 clinical types representing 11 different enzyme deficiencies, only MPS III (Sanfilippo syndromes A, B, C and D) and severe forms of MPS I (Hurler's syndrome), MPS II (severe Hunter syndrome) and MPS VII (severe Sly syndrome) give rise to progressive cerebral disease. Neurosensory complications (hearing impairment, retinopathy and optic atrophy) can also occur in some types. Carpal (or even tarsal) tunnel syndrome is a common complication of the MPS, except for MPS III and MPS IV. Hydrocephalus due to abnormal circulation or resorption of cerebrospinal fluid, chronic spinal compression may occur as complications of MPS I, II and VII and also in MPS IV and VI. Atlanto-axial instability may be observed in type IV and I. (C) 2014 Elsevier Masson SAS. All rights reserved.