Neurological manifestations of Erdheim-Chester disease and their management: A scoping review

Erdheim-Chester disease (ECD) is characterized by the excessive production and accumulation of histiocytes, particularly foamy histiocytes encircled by fibrosis, in various organs. ECD can affect a person's long bones, skin, lungs, brain, heart, and other tissues and organs.

In February 2024, we conducted a thorough literature search on main databases to find studies published between 2021 and 2024. We used keywords like "ECD CNS," "ECD Neuro," "Erdheim Chester Disease CNS," "histiocytosis," and "Erdheim Chester Disease Neurology." We first produced 461 articles and then limited the selection process to 29 articles using an English language filter and an abstract analysis. In the end 16 articles were added in the review on ECD with neurological symptoms.

Ataxia, cranial neuropathies, and cognitive impairment were the main clinical findings. Histopathology showed that 88% of the cases had histiocyte infiltrates with CD68 + histiocytes, 50% had a BRAF mutation, and 83.3% had an expanding mass. The most common treatment was vemurafenib, followed by steroids, surgery, and chemotherapy. Results revealed 15.78% mortality, 26.31% progression, and 31.57% improvement or stabilization. In most cases, steroid medication proved useless; however, vemurafenib and radiation therapy helped some patients' symptoms.

An early diagnosis of the disease is important for timely intervention, to prevent fatal outcomes. Vemurafenib was the only drug which proved its efficacy against the disease, as compared to other drugs. This study presents valuable insights for the neurology of ECD and highlights the benefits of a comprehensive management for this complex condition.