Erdheim-Chester Disease Presenting With Intractable Exophthalmos and Bone Lesions

Abstract

A 71-year-old woman, with a history of central diabetes insipidus, presented with bilateral exophthalmos, chemosis ( Figure A), blindness and bone pain. For the past year, she developed progressively worsening bulging of the eyes and visual acuity despite treatment with oral steroids and subsequent retrobulbar radiotherapy. She also described nighttime gnawing bone pain, more prominent around her knees and ankles. No signs or symptoms of thyrotoxicosis were present. Thyroid stimulating immunoglobulin levels, antinuclear and antineutrophilic cytoplasmic antibodies were undetectable. Whole-body bone scan showed increased tracer activities mostly in the metaphyses of the long bones within the lower extremities. Orbital magnetic resonance imaging demonstrated markedly increased intraconal retrobulbar soft tissue. Surgical orbital decompression was performed, and pathology revealed foamy-histiocytic infiltration (Figure B, arrows) with interspersed inflammatory cells in a fibrotic background (Figure B). Immunostaining was positive for CD68 and negative for CD1a, consistent with Erdheim-Chester disease. After exploring all the therapeutic options with the patient, she refused further intervention and was discharged home. Erdheim-Chester disease is a rare non–Langerhans histiocytosis seen predominantly in adults. It is characterized by osteosclerotic lesions of long bones, cardiac infiltration and retroperitoneal involvement. 1 Veyssier-Belot C. Cacoub P. Caparros-Lefebvre D. et al. Erdheim-Chester disease. Clinical and radiologic characteristics of 59 cases. Medicine. 1996; 75: 157-169 Crossref PubMed Scopus (551) Google Scholar Non–Langerhans histiocytosis differs from Langerhans cell histocytosis in the lack of expression of CD1a and S100. Currently, there is no cure for this disease. However, multiple studies done with high-dose peginterferon-alfa, vemurafenib and chemotherapy demonstrated promising results with survival benefits and decreased histiocytic orbital infiltration. 2 Diamond E.L. Dagna L. Hyman D.M. et al. Consensus guidelines for the diagnosis and clinical management of Erdheim-Chester disease. Blood. 2014; 124: 483-492 Crossref PubMed Scopus (369) Google Scholar