Access Keys:
Skip to content (Access Key - 0)

Eosinophilic granuloma

Tumor biology

  • Rare, benign, tumor-like disorder
  • Belongs to a group of disorders of the reticuloendothelial system
  • Also known as Histocytosis X, or Langerhan's cell histiocytosis (LCH)
  • Involves skeleton as either a solitary lesion or in multiple sites
  • Generally active or aggressive in behavior


  • Most common from ages 5-10
  • Rare after age 30


M:F = 2:1

Associated syndromes


  • Pain most frequent presenting symptom
  • Pediatric patient may present with limp, back pain, or scoliosis

Physical findings

  • Palpable mass may be present (rare).
  • Tenderness at site of symptomatic involvement
  • Scoliosis or restricted motion common with spinal lesions

Plain films

  • Single collapsed vertebra in children (vertebra plana)
  • Lytic lesion of long bones or flat bones with variable degree of endosteal and periosteal response (may appear as permeative, aggressive, lytic lesion)
  • Multiple lesions not uncommon
  • Skull, ribs, vertebrae, pelvis and long bones (femur and humerus mostly)
  • Hands and feet almost never affected
  • Ribs more commonly affected in adults; the long bones more commonly affected in children
  • Lesions may be diaphyseal or metaphyseal


Tumor effect on bone
  • Variable
  • Lytic
  • Destruction can be patchy and uneven; more commonly geographic
  • Rib lesions may expand bone as opposed to long bone lesions, where expansion is less common
  • Pathologic fracture is common in the spine (vertebra plana)
Bone response to tumor
  • Usually minimal metaphyseal sclerosis
  • May be periosteal reaction in response to an endosteal erosive lesion
  • Onion skinning may be present
  • Generally no matrix at presentation in symptomatic phase
  • Can have a hazy matrix during the resolution phase; results from bone forming in lytic lesion
  • Cortex may be thinned, scalloped, or have an onion skinned appearance
  • Differential diagnosis for such onion skinning includes eosinophillic granuloma, non-Hodgkin's lymphoma, and Ewing sarcoma
Soft tissue mass

Rarely present

Differential diagnosis

  • Unicameral bone cyst
    • More commonly larger, less painful, and located in the metaphysis of a bone; eosinophillic granuloma more commonly in diaphysis
  • Osteomyelitis
  • Primary osseous malignancy, such as Ewing sarcoma or lymphoma

Natural history

  • Lesions can progress or disappear over time (can be a few months or longer)
  • Most lesions require diagnostic biopsy, which stimulates resolution of lesion in some cases
  • Persistent aggressive changes may be seen in patients with multiple lesions


  • Gross: Friable tan tissue
  • Microscopic: Infiltrate of histiocytes, Langerhans' cells, and inflammatory cells
    • Variable numbers of eosinophils present
    • Multinucleated giant cells are seen
  • Langerhans' cell is diagnostic cell
    • S100 positive on immunohistochemical staining
    • Contains characteristic Birbeck granules (tennis racket-shaped cytoplasmic inclusions) when examined by electron microscopy


  • Lesions typically observed because they often heal spontaneously
  • Indications for surgery
    • Determine the diagnosis
    • Persistent pain
    • Prevention or treatment of pathologic fracture
  • Curettage and bone graft especially indicated for lower extremity lesions; supplement with internal fixation if patient at risk for fracture
  • Low-dose radiation effective in most lesions, but usually reserved for recalcitrant non-healing or recurrent lesions
  • Multiple lesions or visceral involvement may respond to chemotherapy

Peer Review

OrthopaedicsOne Peer Review Workflow is an innovative platform that allows the process of peer review to occur right within an OrthopaedicsOne article in an open, transparent and flexible manner. Learn more

Instructions for Authors

Read our Instructions for Authors to learn about contributing or editing articles on OrthopaedicsOne.

Content Partner

Learn about becoming an OrthopaedicsOne Content Partner.

Academic Resources

Resources on Eosinophilic granuloma from Pubget.

The license could not be verified: License Certificate has expired!
Orthopaedic Web Links

Internet resources validated by

The license could not be verified: License Certificate has expired!
Related Content

Resources on Eosinophilic granuloma and related topics in OrthopaedicsOne spaces.

Page: Eosinophilic granuloma (OrthopaedicsOne Articles)
Page: Osteoid osteoma (OrthopaedicsOne Articles)
Page: Unicameral bone cyst (OrthopaedicsOne Articles)
Page: Chondroblastoma (OrthopaedicsOne Articles)
Page: Fibrous dysplasia (OrthopaedicsOne Articles)
Page: Giant cell tumor (OrthopaedicsOne Articles)
Page: Osteoblastoma (OrthopaedicsOne Articles)
Page: Aneurysmal bone cyst (OrthopaedicsOne Articles)
Page: Osteochondroma (OrthopaedicsOne Articles)
Page: Fibrous cortical defect (OrthopaedicsOne Articles)
Showing first 10 of 449 results