Erdheim-Chester Disease Cases Highlight Diagnostic Complexity and Treatment Outcomes
A case series of three Erdheim-Chester disease patients demonstrates the disease's diagnostic challenges, with one patient improving on targeted BRAF inhibition while two others died within a year. The rare histiocytosis often presents with multisystem involvement, delaying diagnosis.
A case series of three patients with Erdheim-Chester disease (ECD) illustrates the condition's diagnostic challenges and highly variable clinical course, with one patient achieving improvement on targeted therapy while two others died within a year. ECD is a rare, non-Langerhans cell histiocytosis characterized by excessive accumulation of histiocytes, and more than 80% of cases are associated with mutations activating the Mitogen-Activated Protein Kinase (MAPK) pathway, mainly the v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) V600E mutation.
The case series describes three elderly patients with multisystemic involvement. The first case involved an elderly woman with retroperitoneal and pericardial involvement who developed urinary sepsis and died shortly after diagnosis. A biopsy of her perirenal mass revealed infiltration by foamy cytoplasmic macrophages compatible with ECD, though genetic testing did not find the BRAF V600E mutation.
The second case was a man in his early 70s with cardiovascular and renal involvement who did not respond to treatment with corticosteroids or peginterferon alfa-2a. He died within a year of diagnosis. His mediastinal mass biopsy showed macrophage infiltration positive for CD68, and genetic analysis confirmed the BRAF V600E mutation.
The third case, also a man in his seventies, presented with similar multisystemic disease but achieved clinical and radiological improvement following targeted v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) inhibition. These cases demonstrate the heterogeneous course of ECD and the critical importance of early recognition and tailored therapy.