Sanfilippo type C disease: clinical findings in four patients with a new variant of mucopolysaccharidosis III.

A new genetic variant of the Sanfilippo syndrome due to deficiency of acetyl CoA: alpha-glucosaminide N-acetyltransferase, was recently demonstrated in four patients. The clinical findings of these patients are reported here. Differential diagnosis from other types of the Sanfilippo syndrome on clinical and routine laboratory criteria is difficult and enzyme assay is necessary to reach the diagnosis. Since two of the patients reported are females and consanguinity was present in one case, autosomal recessive inheritance is most probable.