OrthoFracs Logo

Eosinophilic granuloma

Definition

  • Condition at the benign end of the spectrum of histiocytosis X associated with unifocal or multifocal granulomas containing Langerhans cells & eosinophils

Terminology

  • Histiocytosis X comprises a spectrum of disorders.
    • EG
      • most benign. 
    • Hand-Schuller-Christian disease
      • exophthalmos, diabetes insipidus, & bone destruction
    • Letterer-Siwe syndrome
      • Most severe & potentially fatal
      • characterized by hepatosplenomegaly, lymphadenopathy, anaemia, acute infections & a downhill course

Epidemiology

  • First two decades of life
  • Slightly more common in males

Pathology

  • cell of origin is the Langerhans cell, a dendritic antigen presenting cell that is found all throughout the body, particularly in the skin & bones
  • Langerhans cell contains Birbeck granules, & has a nucleus with a deep cleft
  • Other cells found in the granulomas include eosinophils, PMNLs, giant cells, & mononuclear cells.  The Langerhans cells are arranged in clusters. 
  • Necrosis is very commonly seen
  • Grossly the lesion is soft, tan to reddish & occasionally greenish

Distribution

  • Skull, spine, pelvis & long bones, particularly the femur
  • Most commonly unifocal but may be multifocal – up to 50%
  • Has a preference for the skull & femur in children (sites of haematopoietic tissue) & the pelvis, ribs & skull in adults

Clinical

  • Commonest symptom is pain.  The pain is often worse at night
  • May be accompanied by a palpable mass, fever & a limited range of motion
  • Skin lesions are often seen

Investigations

Laboratory

  • Rarely helpful.  Occasional leukocytosis & elevated ESR.  Usually no eosinophilia

Xray

  • XR typically shows lucent lesion sometimes with sclerosis. 
  • lesion is typically in the medullary canal of the diaphysis of a long bone
  • It can occur in the epiphysis, however, & cross open growth plates
  • It may cause cortical destruction
  • It is the great mimicker & is in the differential diagnosis of any skeletal lesion.  There may be expansion or periosteal reaction
  • In the spine causes vertebra plana

MRI

  • typically low T1 signal & high T2 signal.  Surrounding oedema

Differential diagnosis

  • Osteomyelitis
  • Ewing’s sarcoma

Treatment

  • For EG, treatment is usually observation & the tendency is for resolution.  Healing usually takes at least 5 months. 
  • If there is ongoing pain or a lesion in a weight bearing bone then intralesional corticosteroids or curettage & bone grafting is used
  • Radiotherapy can be used for inaccessible lesions
Bookmark and Share