Neuroanatomical and electroencephalographic correlations in Sanfilippo syndrome, type A.

Waking and all-night-sleeping electroencephalographic recordings were obtained on a boy with Sanfilippo disease, type A. The most striking abnormalities were noted during sleep and included (1) lack of progression through normal sleep stages, (2) absence of vertex waves and normal sleep spindles, (3) inability to stage sleep by the usual criteria, and (4) an unusual alteration of low-amplitude (12 to 15 Hz) activity with generalized delta frequencies. Subsequently, neuropathological examination was performed. The electrophysiological phenomena may be correlated with severe cortical involvement.