Choroido-cerebral calcification syndrome with retardation.

We present a sibship with a rare syndrome characterized by mental retardation, dense calcification of the lateral ventricular choroid plexus, and increased CSF protein. Neurophysiologic studies yielded nonspecific results, and endocrine studies, including parathormone levels, were normal. Simultaneous measurements of CSF and serum calcium, magnesium, and other electrolytes were normal, but the CSF/serum ratio of phosphate was low, suggesting a possible role in the pathogenesis of this syndrome.