title: Conditions associated with leukocytosis in a tertiary care hospital, with particular attention to the role of infection caused by clostridium difficile.
abstract: Few modern studies have enumerated the conditions associated with leukocytosis. Our clinical experience has implicated Clostridium difficile infection in a substantial proportion of patients with leukocytosis. In a prospective, observational study of 400 inpatients with WBC counts of >/=15,000 cells/mm(3), we documented >/=1 infection in 207 patients (53%). Of these 207 patients, 97 (47%) had pneumonia, 60 (29%) had urinary tract infection, 34 (16%) had soft-tissue infection, and 34 (16%) had C. difficile infection. C. difficile infection was present in 25% of patients with WBC counts of >30,000 cells/mm(3) who did not have hematological malignancy. Other causes of leukocytosis in the 400 patients included physiological stress, in 152 patients (38%); medications or drugs, in 42 (11%); hematological disease, in 22 (6%); and necrosis or inflammation, in 22 (6%). C. difficile infection is a prominent cause of leukocytosis and this diagnosis should be considered for patients with WBC counts of >/=15,000 cells/mm(3), even in the absence of diarrheal symptoms.
authors.affiliation: Infectious Disease Section, Medical Service, Veterans Affairs Medical Center, Houston, TX, 77030, USA. daniel.musher@med.va.gov
authors.forename: Anna
authors.initials: A
authors.lastname: Wanahita
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Goldsmith
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Musher
mesh_terms: D000328:Adult; D016360:Clostridioides difficile; D004761:Enterocolitis, Pseudomembranous / Q000150:complications* / Q000382:microbiology; D006760:Hospitalization; D006801:Humans; D007958:Leukocyte Count; D007964:Leukocytosis / Q000150:complications* / Q000382:microbiology; D008297:Male; D009336:Necrosis; D010045:Outpatients; D011446:Prospective Studies; D013312:Stress, Physiological / Q000209:etiology