[Cerebral Erdheim-Chester disease].

We report the case of a 26-old-year man hospitalized for first partial complex epileptic seizure. Brain MRI showed an asymptomatic pseudo-tumor lesion in the brainstem. Diabetes insipidus, hypophyseal gonadotropic deficiency and osteosclerosis of long bones strongly suggested Erdheim-Chester disease, a rare histiocytosis, confirmed after tibial biopsy. Six months later, the patient remained stable. A persistent, and even increased, enhancement with Gd-DTPA on brain MR images was noted as previously described. The review of the literature collected 64 cases, and only 7 cases of cerebral "tumor".