title: Utility of routine laboratory testing in management of chronic urticaria/angioedema.
abstract: BACKGROUND
  Laboratory tests are routinely ordered to identify or rule out a cause in patients with chronic urticaria/angioedema (CUA). The results of these tests are usually within normal limits or unremarkable.
  
  
  OBJECTIVE
  To investigate the proportion of abnormal test results in patients with CUA leading to a change in management and in outcomes of care.
  
  
  METHODS
  Retrospective analysis of a random sample of adult patients with CUA from 2001-2009.
  
  
  RESULTS
  Cases totaled 356: 166 with urticaria and angioedema (AE), 187 with urticaria, and 3 with only AE. Patients were predominately women (69.1%) and white (75.6%), with a mean age of 48 ± 15 years. Abnormalities were commonly seen in complete blood counts (34%) and in complete metabolic panels (9.4%). Among the 1,872 tests that were ordered, results of 319 (17%) were abnormal. Of 356 patients, 30 underwent further testing because of abnormalities in laboratory work. This represented 30 of 1,872 tests (1.60%). Only 1 patient benefited from a subsequent change in management.
  
  
  CONCLUSIONS
  Laboratory testing in CUA patients referred for an Allergy and Immunology evaluation rarely lead to changes in management resulting in improved outcomes of care.
authors.affiliation: Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
authors.forename: James A
authors.initials: JA
authors.lastname: Tarbox
authors.forename: Ravi C
authors.initials: RC
authors.lastname: Gutta
authors.forename: Cristine
authors.initials: C
authors.lastname: Radojicic
authors.forename: David M
authors.initials: DM
authors.lastname: Lang
mesh_terms: D000328:Adult; D000799:Angioedema / Q000175:diagnosis* / Q000188:drug therapy*; D001772:Blood Cell Count; D002908:Chronic Disease; D003955:Diagnostic Tests, Routine; D004316:Doxepin / Q000627:therapeutic use; D005260:Female; D006633:Histamine Antagonists / Q000627:therapeutic use; D006801:Humans; D007755:Laboratories, Hospital / Q000191:economics; D008297:Male; D053858:Metabolic Networks and Pathways; D008875:Middle Aged; D012189:Retrospective Studies; D012737:Sex Factors; D016896:Treatment Outcome
chemical_list: D006633:Histamine Antagonists; D004316:Doxepin