Endocrine Abstracts

Erdheim Chester disease (ECD) is a non langheransian rare histiocytosis, with around 500 cases described worldwide since its discovery for the first time in 1930 by Jakob Erdheim et William Chester. It is a multivisceral disease, characterized by a proliferation of abnormal histocytes CD68 positive and CD1a negative, including a retroperitoneal and perirenal fibrosis, a peri-aortitis, an osteosclerosis of the lower limbs and sometime an exophthalmia or an diabetes insipidus. However, cases may be non-typic and confusing. We report the case of the patient B.K aged of 31 years old, followed for diabetes insipidus with an enlarged pituitary stalk evolving for 10 year, posing an etiological diagnostic problem. Sarcoidosis have been first discussed without à lot of arguments, conducing to the introduction of corticotherapy, with a morphological response (regression of the stalk enlargement on the IRM). The patient has been regularly followed and 9 years after, an expansion of the pituitary stalk led us to reevaluate him. A thoraco-abdominal CT has found a retroperitoneal infiltration (peri-pancreatic) which helped us to discuss Erdheim Chester disease. Bone scintigraphy has found multiple fixations on long bones of the lower limbs. A cutaneous localization as a xanthélasma on the lower eyelids is describe with recurrent outbreaks of headache with fever. The diagnosis of certainty was obtained by an immunohistochemical study on biopsy of the bone marrow, finding squamous histocytes expressing CD68, weakly PS100, without expression of CD1a and nuclear expression of D1 cylinder. We have introduced an antagonist interleukin 1 receptor (Anakinra) with a good clinic-biological response. The etiologic diagnostic of a pituitary stalk enlargement is often complicated, it is essential to maintain a clinical and morphological follow-up and discuss rare disease as Erdheim Chester histiocytosis.