Eosinophilic granuloma

Eosinophilic granuloma is a rare condition that is part of a spectrum of diseases known as Langerhans cell histiocytosis (LCH). This spectrum ranges from isolated bone lesions, which characterize eosinophilic granuloma, to multisystem disease. Eosinophilic granuloma primarily affects the skeletal system but may also involve other organs and systems. The disease is characterized by the proliferation of Langerhans cells, a type of dendritic cell that normally functions in the immune system. These cells, along with eosinophils, a type of white blood cell, form lesions or granulomas in the bone and sometimes in other tissues.

Symptoms and Diagnosis

The symptoms of eosinophilic granuloma can vary widely depending on the location and number of lesions. Common sites for these lesions include the skull, spine, ribs, and long bones. Symptoms may include localized pain, swelling, and, in cases where the spine is affected, neurological symptoms due to compression of nerves. When the disease affects the lungs, patients may experience respiratory symptoms.

Diagnosis of eosinophilic granuloma involves a combination of clinical evaluation, imaging studies such as X-rays and MRI, and biopsy of the lesion. The presence of Langerhans cells in the biopsy sample is a key diagnostic feature. These cells can be identified by their unique morphology and by immunohistochemical staining for specific markers such as CD1a and S-100 protein.

Treatment

Treatment for eosinophilic granuloma varies based on the severity and location of the lesions. Options may include observation for spontaneously resolving lesions, surgical removal, corticosteroid injections, radiation therapy, and systemic therapies such as chemotherapy for more aggressive or widespread disease. The choice of treatment depends on factors such as the number of lesions, their location, and the presence of symptoms.

Prognosis

The prognosis for individuals with eosinophilic granuloma is generally good, especially for those with a single bone lesion, which often resolves spontaneously or with minimal intervention. However, the disease can be more serious and require more aggressive treatment when multiple systems are involved.

Epidemiology

Eosinophilic granuloma is the most common form of Langerhans cell histiocytosis, but overall, it remains a rare disease. It can occur at any age but is most commonly diagnosed in children and young adults. There is a slight male predominance.

See Also

• Langerhans cell histiocytosis
• Histiocytosis
• Bone lesion