Erdheim-Chester Disease (ECD) is a rare and complex form of histiocytosis, impacting multiple organ systems with varying degrees of severity. While some patients experience mild symptoms, others face life-threatening complications due to widespread organ involvement. Understanding how ECD affects different parts of the body is crucial for early detection, management, and improved quality of life for patients and their families.

Bone: The Most Commonly Affected Organ

One of the hallmark characteristics of ECD is bone involvement, particularly in the long bones of the legs. Patients often experience bone pain, which can be mistaken for arthritis or other musculoskeletal conditions. Imaging studies, such as X-rays or bone scans, frequently reveal symmetric sclerosis, a defining feature of the disease. While bone involvement is not usually life-threatening, it can significantly impact mobility and daily function.

Brain: A Critical and Challenging Manifestation

Central nervous system (CNS) involvement occurs in up to 50% of ECD patients and is a major prognostic factor. Symptoms vary widely, including cognitive impairment, coordination difficulties, vision problems, and diabetes insipidus (a condition that leads to excessive thirst and urination due to pituitary gland dysfunction). Because neurological symptoms can be subtle at first, they are often misdiagnosed or attributed to other conditions. Proper imaging and neurological evaluations are essential for timely diagnosis and intervention.

Kidney: The “Hairy Kidney” Sign and Organ Dysfunction

About half of ECD patients develop kidney involvement, typically characterized by a “hairy kidney” appearance on imaging scans due to perinephric fibrosis. This can lead to impaired kidney function and, in severe cases, kidney failure. The progressive fibrotic process may also affect the ureters, leading to urinary obstruction and further complications.

Heart: A Silent but Serious Risk

Cardiac involvement in ECD can manifest in several ways, including pericardial thickening, restrictive pericarditis, and pseudotumoral infiltration of the right atrium. While some patients remain asymptomatic, others experience heart failure symptoms such as shortness of breath, chest pain, and fatigue. Due to the potential for sudden and severe complications, regular cardiac evaluations are essential for ECD patients.

Skin: An Often Overlooked Clue

Although less common, ECD can affect the skin, causing xanthomas (yellowish plaques) or reddish-brown lesions, often found around the eyes or on the trunk. These skin manifestations may be an early sign of systemic disease and can aid in diagnosis when biopsied. While not typically dangerous, skin involvement can be an external indicator of underlying internal organ damage.

Connecting Patients and Families Through Knowledge

Recognizing the many faces of ECD is vital for increasing awareness and improving patient outcomes. This is why the upcoming Annual International Patient and Family Gathering in Barcelona on May 26, 2025, is such an important event. It provides a unique opportunity for patients, families, and medical experts to come together, share knowledge, and gain insights into the latest research and treatment advancements.

Whether you are newly diagnosed or have been managing ECD for years, this event offers a chance to connect with others who truly understand your journey. The more we learn about how ECD affects the body, the better we can advocate for earlier diagnosis, effective treatment, and ultimately, a better quality of life for all those affected.

For more information about the gathering and other ECD resources, visit the Erdheim-Chester Disease Global Alliance (ECDGA) website: www.erdheim-chester.org

The Erdheim-Chester Disease Global Alliance (ECDGA) does not provide medical advice, diagnoses, or treatments. All content is for informational purposes only. Please consult with a healthcare provider for medical concerns.