title: A 2-year-old boy with knee pain, fever, and multiple birthmarks.
authors: 1University of Maryland, Baltimore, MD, USA.
authors: Rosa
authors: R
authors: Nguyen
authors: John
authors: J
authors: Kim
authors: Narendra
authors: N
authors: Shet
authors: Bertrand M
authors: BM
authors: Janne d'Othée
authors: Carol L
authors: CL
authors: Greene
mesh_terms: D018771:Arthralgia / Q000209:etiology*; D002675:Child, Preschool; D005266:Femoral Neoplasms / Q000150:complications / Q000175:diagnosis*; D005335:Fever of Unknown Origin / Q000209:etiology*; D006391:Hemangioma / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D007719:Knee Joint; D008297:Male; D019042:Muscle Neoplasms / Q000150:complications / Q000175:diagnosis*; D012878:Skin Neoplasms / Q000150:complications / Q000175:diagnosis