Erdheim Chester Disease Presenting as a Hypothalamic-Pituitary Lesion and Hypopituitarism in a Patient with Langerhans Cell Histiocytosis

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SUN 163-194-Pituitary Disorders & Case Reports
Basic/Clinical
Sunday, June 16, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SUN-173
Sumbul A Ali*1, Kenneth McClain2, Daniel Yoshor3 and Susan Leanne Samson4
1Baylor College of Medicine, Houston, TX, 2Baylor College of Medicine/Texas Children's Hospital/Histiocytosis Program, 3Pituitary Center/Baylor College of Medicine/St. Luke's Episcopal Hospital, 4Pituitary Center/Baylor College of Medicine/St. Luke's Episcopal Hospital, Houston, TX
Background: Diagnosis of infiltrative disorders of the pituitary gland and hypothalamus is challenging and transsphenoidal biopsy may be the only option for obtaining a histopathologic diagnosis. We report a case of Erdheim Chester Disease (ECD) presenting as a pituitary lesion and diagnosed by transsphenoidal biopsy in a patient with a 20 year history of Langerhans cell histiocytosis (LCH).

Clinical Case: A 43 yo male was diagnosed with a history of LCH at age 24 with biopsy of a scalp rash. A second skin biopsy at age 36 further confirmed LCH.  He had a relapsing remitting course treated with steroids and Vinblastine. In 2005 he developed double vision. Brain MRI revealed a 1.9 x 1.8 cm sellar mass and he underwent transsphenoidal resection. Pathology was initially reported as a pituitary adenoma and follow-up CT scan reportedly showed complete resection. Six years later, he was referred to our Pituitary Center for evaluation of a sellar and hypothalamic lesion. He complained of polyuria, polydipsia, fatigue and hypogonadal symptoms. He was on maintenance methotrexate weekly for his skin LCH and desmopressin for diabetes insipidus (DI). Exam revealed an obese male with sallow skin. Visual fields were full but with some decreased sensitivity in the temporal inferior fields. Morning labs showed: ACTH < 5 ( normal 7-69 pg/ml), cortisol < 0.5 (7-25 ug/dl), LH <0.1 (1.2-7.8 mIU/ml) , FSH 0.8 (1-11.4 mIU/ml), total testosterone <10 (292-867 ng/dl), TSH 2.4 (0.3-5.1 uIU/ml), free T4 0.56 ( 0.73-1.95 ng/dl), IGF-1  41.2 (87-267 ng/ml) and prolactin 4 (3-30 ng/ml). MRI of the sella showed large lobulated heterogeneous and enhancing mass 2.4 x 2.8 x 2.2 cm filling the sella and extending into the suprasellar cistern, with elevation of the optic chiasm. A transsphenoidal biopsy was performed which revealed histiocytes negative for S100 and CD1a but strongly positive for CD68 and CD 163 consistent with Erdheim Chester disease. Xrays of tibiae disclosed mild symmetric osteosclerosis of the bilateral tibial diaphyses consistent with the diagnosis.

Clinical lesson: ECD is a systemic non-Langerhans cell histiocytosis characterized by infiltration of CD68+/CD1a- histiocytes, no Birbeck granules or S-100 immunostaining and symmetric osteosclerosis of the long bones as well as coating of the aorta, heart, kidneys,or globes with fibrinous, histiocytic infiltrates. DI and pituitary involvement are seen in 28% and 22% respectively. This patient had biopsy proven co-existence of LCH and ECD, altering the approach to treatment. ECD would not have been revealed without transsphenoidal biopsy. ECD is rare but part of the differential diagnosis for a pituitary-hypothalamic lesion.

Nothing to Disclose: SAA, KM, DY, SLS

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