Sea-blue histiocyte syndrome with bone anomalies.

Two sisters, now 29 and 24 years old, are described. They presented a congenital storage of, most probably, phospholipids in the histiocytes of the sea-blue type or blue pigmentophages. The granules of these cells showed a PAS positivity and strong positivity for acid phosphatase, but there were negative also for non-specific esterase, naphthol-AS-D-chloracetate esterase and iron acid also for urine mucopolysaccharide. The two cases differed from all the described cases in the absence of hepatosplenomegaly and in the presence of bone changes resembling late spondyloepiphyseal dysplasia or atypical dysostosis multiplex.