Langerhans' cell histiocytosis

Langerhans’ cell histiocytosis

A group of conditions characterised by proliferation of Langerhans cells, which are lymphoreticular cells. Langerhans cell aggregates are nodular, especially in the lungs, and are variably accompanied by eosinophils, foamy cells, neutrophils, and fibrosis.

Prognosis
Good if limited to a single system. Multi-system involvement carries a 10–20% mortality rate due to organ failure; 50–60% have chronic disease; 30–40% have long-term clinical remission.

Langerhans cell histiocytosis types 
Pulmonary LCH
A lesion virtually exclusive to cigarette smokers, which is a form of smoking-related interstitial lung disease. Smoking cessation may lead to reversal of changes or evolution to pulmonary fibrosis and pulmonary hypertension.
 
Unifocal LCH
Eosinophilic granuloma, solitary bone involvement
A lesion affecting younger patients; may affect any bone, most commonly the cranial vault, jaw, humerus, rib and femur (often spares the hands and feet).

Imaging
Mimics Ewing sarcoma.
 
Treatment
Curettage.
 
Prognosis
Excellent.
 
Multifocal unisystem
LCH Hand-Schüller-Christian disease, multiple bone involvement.

Polyostotic eosinophilic granuloma 
A lesion that may affect the skin, accompanied by proptosis, diabetes insipidus, or chronic otitis media or combination thereof, marked by a chronic course with waxing and waning symptoms.

Prognosis
Relatively good.
 
Multifocal multisystem LCH
Letterer-Siwe disease, multiple organ involvement
A lesion that affects bone, lung and skin; while histologically indistinct, it is more aggressive than the other forms.

Prognosis
Poor if < 18 months at time of diagnosis; haemorrhagic skin lesions; hepatomegaly, anemia; thrombocytopenia; bone marrow involvement.

Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

Langerhans' cell histiocytosis

Histiocytosis X, Langerhans cell granulomatosis, multifocal eosinophilic granuloma Hematology An autonomous proliferation of a lymphoreticular cell, the Langerhans cell, which stains positively with antibodies to ATPase, S-100 and CD1a; LC aggregates are accompanied by eosinophils, foamy cells, neutrophils, fibrosis; histiocytosis X is divided into 3 clinical forms

Langerhans cell histiocytosis–histiocytosis X  

Solitary bone involvement Eosinophilic granuloma A lesion of younger Pts; may affect any bone–spares hands & feet, most commonly, the cranial vault, jaw, humerus, rib & femur. Radiology Mimics Ewing sarcoma. Treatment Curettage. Prognosis Excellent

Multiple bone involvement Polyostotic eosinophilic granuloma, Hand-Schüller-Christian disease
A lesion that variably affects the skin, accompanied by proptosis, diabetes insipidus, or chronic otitis media or combination thereof, marked by a prolonged course with waxing and waning symptoms Prognosis Relatively good

Multiple organ involvement Letterer-Siwe disease A lesion that affects bone, lung and skin, which while histologically indistinct, but more aggressive than the other forms Prognosis Poor if < 18 months at time of diagnosis, hemorrhagic skin lesions, hepatomegaly, anemia, thrombocytopenia, BM involvement

McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.