title: Elevated granulocyte colony-stimulating factor, non-infectious leukocytosis and fevers in a patient with multiple myeloma.
abstract: BACKGROUND
  We report the case of a 56-year-old male with multiple myeloma in whom recurrent fevers and leukocytosis delayed potentially effective chemotherapy due to concern for active infection.
  
  
  METHODS
  A thorough infectious workup, including CT and PET scans, was negative. The patient was eventually found to have an elevated serum granulocyte colony-stimulating factor (G-CSF) of 113 pg/ml (normal range 0.0 - 39.1 pg/ml), which was likely the cause of his persistent leukocytosis and fevers. Multiagent chemotherapy was initiated, and the fevers resolved in the next 4 days.
  
  
  RESULTS
  Leukocyte concentrations trended down after initiation of chemotherapy, but it is uncertain how much of the decline was attributable to immunosuppression.
  
  
  CONCLUSIONS
  We report this well-documented case to demonstrate that G-CSF production should be considered as a cause of unexplained fever and leukocytosis in patients with multiple myeloma to prevent inappropriate and delayed definitive diagnosis and treatment.
authors.affiliation: University of Minnesota Medical Center, Minneapolis, MN, USA. seba0027@umn.edu
authors.forename: Meghan M
authors.initials: MM
authors.lastname: Sebasky
authors.forename: Pankaj
authors.initials: P
authors.lastname: Gupta
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Filice
mesh_terms: D005334:Fever / Q000150:complications* / Q000175:diagnosis*; D016179:Granulocyte Colony-Stimulating Factor / Q000096:biosynthesis* / Q000097:blood; D006801:Humans; D007964:Leukocytosis / Q000097:blood / Q000150:complications* / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000097:blood / Q000150:complications* / Q000175:diagnosis*
chemical_list: D016179:Granulocyte Colony-Stimulating Factor