Letterer-Siwe Disease Definition

lĕt ′ ər-ər-sī ′ wē, -sē ′ və
noun
An often fatal form of Langerhans cell histiocytosis usually occurring in infants and characterized by maculopapular rash, lymphadenopathy, hepatosplenomegaly, gingival inflammation, and anemia.
American Heritage Medicine

(medicine, dated) Langerhans cell histiocytosis.

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