MR of diabetes insipidus in a patient with Erdheim-Chester disease: case report.

Twenty-six cases of Erdheim-Chester disease have been reported since it was first described in 1930 [1, 2] . The typical pathologic feature is an infiltration of foamy, lipid-laden histiocytes and giant cells [3] . Characteristic skeletal radiographic abnormalities are symmetric osteoblastic changes with or without lytic components in the major long bones, especially the diaphysis and metaphysis [4, 5) . Bone-seeking radiopharmaceutical agents and gallium may accumulate in areas of radiographic abnormalities [6, 7]. Extraskeletal involvement with lipid-laden histiocytes has been seen in virtually every major visceral organ [2 , 8-11 ). CNS involvement is, however, highly unusual, except for retrogloballesions [9 , 11 , 12] and infiltration presenting as multiple parasagittal masses [11 , 12]. In their review of 19 cases of the disease, Miller et al. [11) found only one instance of central diabetes insipidus and hypopituitarism. We report a rare case of neurogenic diabetes insipidus associated with Erdheim-Chester disease.