[Case of early hydrocephalus in mucopolysaccharidosis type 1].

One mucopolysaccharidosis I-H (Hurler's Syndrome) found in 3 months infant, was complicated with an hydrocephalus at the age of 5 months. If macrocephaly is known in several genetic inborn errors of metabolism, specially in the different mucopolysaccharidosis, hydrocephalus is quite more rare. It is probably communicating and due to accumulation of storage material in the piaarachnoid causing an impairment in CSF absorption. It occurs in the evolution of the disease and the reported cases concern only older children; our case is special by the early beginning of hydrocephalus.