title: Mercaptopurine-induced fever in a patient with Crohn's disease.
abstract: OBJECTIVE
  To report a case of mercaptopurine-induced fever.
  
  
  METHODS
  A patient with Crohn's disease was treated with mercaptopurine (6-MP) for an exacerbation of his illness. The patient developed fever and chills. After thorough diagnostic examinations and failure to respond to antimicrobial therapy, symptoms were attributed to an allergic-type reaction to 6-MP. The patient defervesced after 6-MP withdrawal. Fever and chills, along with arthralgias, recurred upon rechallenge with a single dose of 6-MP.
  
  
  CONCLUSIONS
  Adverse effects attributable to 6-MP therapy in inflammatory bowel disease were reviewed in the literature. Drug-induced fever has been previously reported; however, it is an uncommon adverse effect and is difficult to diagnose. It is also difficult to predict which patients will have the reaction. It is a diagnosis of exclusion requiring a thorough investigation.
  
  
  CONCLUSIONS
  Drug-induced fever should be considered when confronted with fever and chills in patients with inflammatory bowel disease being treated with 6-MP. This case report shows the difficulty in differentiating between an infectious process and an adverse reaction to a medication.
authors.affiliation: Department of Emergency Medicine, Monmouth Medical Center, Long Branch, NJ 07740.
authors.forename: E L
authors.initials: EL
authors.lastname: Rehr
authors.forename: K A
authors.initials: KA
authors.lastname: Swanson
authors.forename: J A
authors.initials: JA
authors.lastname: Kern
mesh_terms: D003424:Crohn Disease / Q000188:drug therapy*; D004342:Drug Hypersensitivity / Q000209:etiology; D005334:Fever / Q000139:chemically induced*; D006801:Humans; D008297:Male; D015122:Mercaptopurine / Q000009:adverse effects* / Q000627:therapeutic use; D008875:Middle Aged
chemical_list: D015122:Mercaptopurine