SHM Converge Scientific Abstract ePoster Gallery-Sometimes, It's a Zebra: A Rare Presentation of Erdheim-Chester Disease

Pdf Summary

This case report describes a 63-year-old man with progressive anasarca, macrocytic anemia, acute kidney injury, severe hypoproteinemia, vitamin deficiencies, hypocholesterolemia, hepatic synthetic dysfunction, and marked coagulopathy. His workup was extensive and initially inconclusive, prompting multiple multidisciplinary discussions and prolonged hospitalization.<br /><br />Ultimately, the patient was diagnosed with Erdheim-Chester disease (ECD), a very rare non-Langerhans cell histiocytic multisystem disorder with fewer than 1,000 reported cases. The diagnosis was challenging because no single test was definitive; instead, it relied on a combination of clinical findings, imaging, and pathology. Supporting features included long-bone sclerosis on x-rays, xanthogranulomas on a prior conjunctival biopsy, lipid-laden histiocytes and Touton giant cells on skin biopsy, and foamy histiocytes in bone marrow biopsy.<br /><br />The report emphasizes that although about 95% of ECD cases involve mutations in a MAP-kinase pathway gene, this mutation was not present in the patient. ECD often affects multiple organ systems, including bone, cardiovascular, neurologic, endocrine, pulmonary, thyroid, kidney, spleen, and others.<br /><br />The patient improved after treatment with cobimetinib, but uncertainty about the diagnosis remained. The authors use this case to highlight the limits of modern diagnostic testing and the importance of maintaining strong physical exam skills, using case-specific clinical judgment, and collaborating across specialties when facing diagnostic uncertainty.

Asset Subtitle

Sarah Li

Meta Tag

Author List Lucy Cho, Sarah Li

Category Clinical Vignettes

Concept Erdheim-Chester Disease

Concept Long-Bone Sclerosis

Concept Foamy Histiocyte

Concept Multidisciplinary Diagnosis

Concept Non-Langerhans Histiocytosis

Distinguished Non-Finalist

Presenter Organization Oregon Health & Science University

Presenting Author Sarah Li

Track Adult

Keywords

Erdheim-Chester disease

anasarca

macrocytic anemia

acute kidney injury

hypoproteinemia

coagulopathy

xanthogranulomas

Touton giant cells

MAP-kinase mutation

cobimetinib

Erdheim-Chester Disease

Long-Bone Sclerosis

Foamy Histiocyte

Multidisciplinary Diagnosis

Non-Langerhans Histiocytosis