
It is disease that primarily affects bone but occasionally may also affect other organ system and present in multisystemic pattern.
It is a group of idiopathic disorders characterized by clonal proliferation of specialized bone marrow.
It is also known as Langerhans Cell Histiocytosis (LCH). It is dendritic cell disorder

Clinical features :-
- Pain, swelling or lump in a bone that does not go away.
- Broken bone from only a minor injury or for no apparent reason.
- Loose teeth (when not expected) or swollen gums.
- Ear infection, cysts in the ear or fluid oozing from the ear.
- Skin rash, such as on the scalp or buttocks.
Clinical syndromes :-
- Letterer-siwe disease
- Eosinophilic granuloma
- Hand-schuller-christian disease
Histopathology :-

- Convoluted vesicular chromatin is seen
- Small nucleolus is seen
- Light blue dendritic is seen
- Convoluted peripheral heterochromatin is seen
Treatment :-
- Steroid therapy, such as prednisone, is used to treat LCH lesions.
- Bisphosphonate therapy (such as pamidronate, zoledronate, or alendronate) is used to treat LCH lesions of the bone.
- Local curettage or excision of lesions. Heal on it’s own. Prognosis is good.
Reference :-
Image :- Google
Writing :- notes made from mastering bds and Sanjay Kumar Purkait books