title: Comparison of automated versus manual neutrophil counts for the detection of cellular abnormalities in dogs receiving chemotherapy: 50 cases (May to June 2008).
abstract: OBJECTIVE
  To determine the frequency of clinically relevant abnormalities missed by failure to perform a blood smear evaluation in a specific subset of dogs receiving chemotherapy and to compare automated and manual neutrophil counts in the same population.
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  50 dogs receiving chemotherapy with a total nucleated cell count > 4,000 nucleated cells/μL.
  
  
  METHODS
  50 blood smears were evaluated for abnormalities that have strong potential to change the medical plan for a patient: presence of blast cells, band neutrophils, nucleated RBCs, toxic change, hemoparasites, schistocytes, and spherocytes. Automated and manual neutrophil counts were compared.
  
  
  RESULTS
  Blood smears from 10 (20%) patients had ≥ 1 abnormalities. Blast cells were identified on 4 (8%) blood smears, increased nucleated RBCs were identified on 5 (10%), and very mild toxic change was identified on 2 (4%). Correlation coefficient of the neutrophil counts was 0.96. Analysis revealed a slight bias between the automated and manual neutrophil counts (mean ± SD difference, -0.43 × 10(3)/μL ± 1.10 × 10(3)/μL).
  
  
  CONCLUSIONS
  In this series of patients, neutrophil count correlation was very good. Clinically relevant abnormalities were found on 20% of the blood smears. An automated CBC appears to be accurate for neutrophil counts, but a microscopic examination of the corresponding blood smear is still recommended; further studies are needed to determine whether the detection or frequency of these abnormalities would differ dependent on chemotherapy protocol, neoplastic disease, and decision thresholds used by the oncologist in the ordering of a CBC without a blood smear evaluation.
authors.affiliation: Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA. coramc@niehs.nih.gov
authors.forename: Michelle C
authors.initials: MC
authors.lastname: Cora
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Neel
authors.forename: Carol B
authors.initials: CB
authors.lastname: Grindem
authors.forename: Grace E
authors.initials: GE
authors.lastname: Kissling
authors.forename: Paul R
authors.initials: PR
authors.lastname: Hess
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D004283:Dog Diseases / Q000097:blood* / Q000188:drug therapy; D004285:Dogs; D009369:Neoplasms / Q000188:drug therapy / Q000662:veterinary; D009503:Neutropenia / Q000139:chemically induced / Q000175:diagnosis / Q000662:veterinary*; D009504:Neutrophils / Q000502:physiology*; D012189:Retrospective Studies
chemical_list: D000970:Antineoplastic Agents