title: Association of leukocytosis with amphetamine and cocaine use.
abstract: OBJECTIVE
  Determining the etiology of unexplained leukocytosis in asymptomatic patients may incur unnecessary testing, cost, and prolonged emergency department stay. The objective was to delineate if use of amphetamines and/or cocaine is a factor.
  
  
  METHODS
  For two years we reviewed all psychiatric patients presenting for medical clearance with exclusions for infection, epilepsy, trauma, or other nonpsychiatric medical conditions.
  
  
  RESULTS
  With a total of 1,206 patients, 877 (72.7%) amphetamines/cocaine-negative drug screen controls had mean WBC 8.4 ± 2.6 × 10³/µL. The 240 (19.9%) amphetamines-positive, cocaine-negative, patients had WBC 9.4 ± 3.3 × 10³/µL (P < 0.0001). The 72 (6.0%) amphetamines-negative, cocaine-positive, patients had WBC 7.1 ± 1.8 × 10³/µL (P < 0.0001). The remaining 17 (1.4%) amphetamines/cocaine-positive patients had WBC 10.0 ± 4.2 × 10³/µL (P = 0.01). Amphetamines-positive patients had a supranormal WBC ratio significantly higher than controls (23.8% versus 14.8%, P = 0.001), whereas only one cocaine-positive patient had a supranormal WBC count, with significantly lower ratio (1.4%, P = 0.0003).
  
  
  CONCLUSIONS
  Use of amphetamines, not cocaine, may be associated with idiopathic leukocytosis. This may be explained by unique pharmacologic, neuroendocrine, and immunomodulatory differences.
authors.affiliation: Department of Emergency Medicine, PSSB 2100, U.C. Davis Medical Center, 2315 Stockton Boulevard, Sacramento, CA 95817, USA.
authors.forename: John R
authors.initials: JR
authors.lastname: Richards
authors.affiliation: Department of Emergency Medicine, PSSB 2100, U.C. Davis Medical Center, 2315 Stockton Boulevard, Sacramento, CA 95817, USA.
authors.forename: Valeria F
authors.initials: VF
authors.lastname: Farias
authors.affiliation: Department of Emergency Medicine, PSSB 2100, U.C. Davis Medical Center, 2315 Stockton Boulevard, Sacramento, CA 95817, USA.
authors.forename: Chris S
authors.initials: CS
authors.lastname: Clingan
mesh_terms: D000328:Adult; D019969:Amphetamine-Related Disorders / Q000097:blood* / Q000150:complications*; D019970:Cocaine-Related Disorders / Q000097:blood* / Q000150:complications*; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D007964:Leukocytosis / Q000097:blood* / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies