Langerhan'c cell Histiocytosis

LANGERHANS CELL HISTIOCYTOSIS or HISTIOCYTOSIS X
  • Proliferation of a special type of immature dendritic cells called Langerhans cell.
  • Langerhan's cells belong to Antigen presenting cells.
  • The nuclei of langerhan's giants cells are arranged around the periphery.
  • Cytoplasm contains Birbeck granules (tubules with dilated terminal end producing a tennis racket like appearance)
  • Tumor cells express HLA-DR, S-100, CD1a
  • Normal epidermal Langerhans cells express CCR6; Neoplastic cells express CCR6 and CCR7
  • Increased risk of ALL
Letterer Siwe disease (multifocal multisystem LCH)
  • Mostly < 2 years of age
  • Characterized by involvement of multiple system.
  • Others are hepatosplenomegaly, lymphadenopathy pulmonary lesions and destructive bone lesions.
  • Extensive bone marrow infiltration leads to pancytopenia.
  • Most common presentation is cutaneous lesions resembling seborrheic dermatitis.
  • Destructive osteolytic bone lesions
  • Bad prognosis 
Eosinophilic granuloma (Unifocal and Multifocal uniisystem LCH)
  • Eosinophils are usually prominent
  • Involvement is restricted to a single system i.e., skeletal system which may be unifocal or multifical. 
  • Most commonly effected bones are skull, vertebrae, ribs, clavicle, and femur.
  • Usually arise in the medullary cavities of bone
  • Posterior pituitary stalk involvement leads to Diabetes Insipidus.
  • Peak incidence : 5-15 years.
Hand Schuller-Christian triad
  • Calvarial bone defects
  • Diabetes Insipidus
  • Exophthalmos
  • Peak incidence:2-10 years
Pulmonary LCH
  • Mostly in adult (20-40 years) smokers
  • Regress spontaneously after smoking cessation
  • Most prominent in upper and middle lung zones
  • X-ray: Bilateral, symmetric ill-defined nodules
Treatment:
  • Treatment is guided by extent of disease.
  1. Solitary bone lesion may be amenable through excision or limited radiation, dosage of 5-10 Gys for children, 24-30 Gys for adults.
  2. However systemic diseases often require chemotherapy.
Exam Question of:
  • Peak incidence is less than 3 years of age in Langerhans cell histiocytosis.(in Letterer Siwe disease)
  • Langerhans cell histiocytosis is radiosensitive.
  • Diffuse form of Langerhans cell histiocytosis is known as litter-sewe-disease.
  • Langerhans cell histiocytosis produce a seborrheic dermatitis like lesions in an infant.
  • CD 1a is a marker of Langerhan's cell histiocytosis.
  • The nuclei of langerhan's giants cells are arranged around the periphery.
  • Localised langerhans cells histiocytosis affecting head & neck is called Eosinophilic Granuloma.
  • X-bodies called Birbeck granules are characteristically seen in Langerhan's cell granulomatosis.
  • The histologic hallmark of langerhan cells is Birbeck granules.
  • Langerhan's histocytosis can be associated with diabetes insipidus.
  • Hand Schuller Christian disease ,Eosinophilic granuloma , Letter-siwe syndrome are the types of Langerhan's cell histiocytosis.
  • Langerhan's cells belong to Antigen presenting cells.

Don't Forget to Solve all the previous Year Question asked on Langerhan'c cell Histiocytosis