letterer-Siwe disease https://github.com/monarch-initiative/mondo/issues/9097 https://www.malacards.org/card/letterer_siwe_disease OMIM:246400 ICD10CM:C96.0 MEDGEN:7311 multifocal multisystem Langerhans cell histiocytosis Orphanet:99870 acute and disseminated Langerhans cell histiocytosis UMLS:C0023381 histiocytosis X, acute disseminated acute disseminated Langerhans cell histiocytosis MONDO:0009519 MedDRA:10024265 letterer-Siwe disease A multifocal, multisystem form of Langerhans-cell histiocytosis. There is involvement of multiple organ systems including the bones, skin, liver, spleen, and lymph nodes. Patients are usually infants presenting with fever, hepatosplenomegaly, lymphadenopathy, bone and skin lesions, and pancytopenia. GARD:0024676 ICDO:9754/3 icd11.foundation:1827474596 L-S disease NCIT:C3160 Langerhans cell histiocytosis specific to childhood