title: A case of Erdheim-Chester disease initially mistaken for Ormond's disease.
abstract: BACKGROUND
  A 54-year-old man presented with fever, abdominal pain, anemia, elevated C-reactive protein level and decreased renal function. Idiopathic retroperitoneal fibrosis (Ormond's disease) had been diagnosed in the past, leading to surgical ureterolysis. Re-evaluation of the CT scans and histological biopsy samples revealed unusual sclerosis of the long bones and diffuse infiltrates of foamy histiocytes in the bone marrow and the retroperitoneum.
  
  
  METHODS
  Physical examination, laboratory tests including hemoglobin concentration, erythrocyte sedimentation rate, C-reactive protein level, beta2-microglobulin level, creatinine level, CT of the chest and abdomen, bone scintigraphy, bone marrow and soft tissue biopsies and immunohistochemistry.
  
  
  METHODS
  Erdheim-Chester disease with retroperitoneal fibrosis and bone sclerosis.
  
  
  RESULTS
  Treatment with glucocorticoids failed. The patient's symptoms improved significantly after initiation of interferon-alpha therapy.
authors.affiliation: Department of Rheumatology and Clinical Immunology, Charité University Medicine, Berlin, Germany. konstanze.loddenkemper@charite.de
authors.forename: Konstanze
authors.initials: K
authors.lastname: Loddenkemper
authors.forename: Bimba
authors.initials: B
authors.lastname: Hoyer
authors.forename: Christoph
authors.initials: C
authors.lastname: Loddenkemper
authors.forename: Kay-Geert
authors.initials: KG
authors.lastname: Hermann
authors.forename: Patrick
authors.initials: P
authors.lastname: Rogalla
authors.forename: Gregor
authors.initials: G
authors.lastname: Förster
authors.forename: Frank
authors.initials: F
authors.lastname: Buttgereit
authors.forename: Falk
authors.initials: F
authors.lastname: Hiepe
authors.forename: Gerd-Rüdiger
authors.initials: GR
authors.lastname: Burmester
mesh_terms: D000740:Anemia / Q000209:etiology; D000970:Antineoplastic Agents / Q000627:therapeutic use; D003937:Diagnosis, Differential; D031249:Erdheim-Chester Disease / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy; D006801:Humans; D006869:Hydronephrosis / Q000209:etiology; D007370:Interferon Type I / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins; D012185:Retroperitoneal Fibrosis / Q000175:diagnosis*
chemical_list: D000970:Antineoplastic Agents; D007370:Interferon Type I; D011994:Recombinant Proteins