Mucolipidosis type IV: clinical manifestations and natural history.

The clinical manifestations and psychomotor development of five patients with mucolipidosis IV (MLIV) from three Ashkenazi-Jewish families are reported. The presenting symptoms were hypotonia, developmental delay, corneal clouding, and puffy eyelids. Four of the patients had convergent strabismus and none progressed beyond a developmental age of 15 months. One patient died of aspiration at 17 years while the oldest patient entered puberty at 20 years, developed a coarse face at 30 years, and is now 32 years old. Histopathological studies in four patients showed storage changes characteristic of MLIV.