[Erdheim-Chester disease: radiological findings]

Area of Science:

• Radiology
• Histiocytosis
• Rare Diseases

Background:

• Erdheim-Chester disease is a rare non-Langerhans histiocytosis.
• Increasingly reported due to improved recognition of its radiological patterns.
• Characterized by specific, recognizable imaging appearances.

Purpose of the Study:

• To illustrate the typical imaging findings of Erdheim-Chester disease.
• To highlight the importance of recognizing specific radiological patterns.
• To emphasize the role of imaging in the diagnosis of Erdheim-Chester disease.

Main Methods:

• Retrospective review of four cases of Erdheim-Chester disease.
• Analysis of findings from X-rays, MRI, bone scintigraphy, and CT.
• Correlation of imaging findings with disease characteristics.

Main Results:

• X-rays show bilateral, symmetric osteosclerosis in long bones, mimicking Paget's disease.
• MRI reveals bone marrow infiltration with characteristic signal intensities.
• Bone scintigraphy demonstrates pathognomonic bilateral increased uptake in femur and tibiae.
• CT identifies visceral and vascular involvement, including "hairy kidney" and perivascular infiltration.

Conclusions:

• Erdheim-Chester disease can be life-threatening.
• Knowledge of specific imaging features is critical for early management.
• Prompt diagnosis through characteristic imaging improves prognosis.