[Refractory Erdheim-Chester disease with central nervous system lesion complicated by central diabetes insipidus]

We report a case of Erdheim-Chester disease (ECD) complicated with central diabetes insipidus that was refractory to several treatments. A 58-year-old female suffered from fatigue, fever, thirst, polyuria, leg pain, xanthoma of her upper eyelids, and disturbance of consciousness. Computed tomography (CT) imaging showed infiltration of perivascular soft tissue surrounding the aorta, hydronephrosis, and sclerotic lesions of the femurs and tibias. Magnetic resonance imaging showed the enhancement of expansile pachymeningeal lesions. A water deprivation test revealed the presence of central diabetes insipidus. The results of skin and bone marrow biopsies were consistent with ECD. The patient was treated with prednisone (30 mg daily) and interferon-α (6 mIU three times/week). The perivascular soft tissue showed a slight improvement, but she experienced cerebral hemorrhage 4 and 8 months later. Subsequently, she was treated biweekly with IV tocilizumab (8 mg/kg). Although her clinical symptoms improved, enlargement of the meningeal tumor and hydrocephalus led to disturbance of consciousness 6 months later. After the surgical debulking of the intracranial lesion, she was treated with two cycles of IV cladribine (0.12 mg/kg for 5 d). She had a transient clinical improvement but developed central nervous system disease marked by progressive neurological symptoms.