title: Grey eosinophils in sighthounds: frequency in 3 breeds and comparison of eosinophil counts determined manually and with 2 hematology analyzers.
abstract: BACKGROUND
  Grey eosinophils (GE) reported to occur in Greyhounds, and occasionally in other breeds, have clear granules, probably due to abnormal staining properties.
  
  
  OBJECTIVE
  The aims of this study were to investigate the frequency of GE in Greyhounds and 2 other sighthound breeds, and to assess the capacity of the ADVIA 120 and Sysmex XT-2000iV hematology analyzers to correctly identify GE.
  
  
  METHODS
  Blood samples from 20 Greyhounds, 29 Italian Greyhounds, and 24 Whippets were analyzed using the ADVIA and Sysmex hematology analyzers, and blood smears stained with May-Grünwald Giemsa were evaluated microscopically. The frequency of samples with GE detected on smears was recorded for each breed. Manual and automated eosinophil counts were compared using a Wilcoxon signed-rank test. Agreement between methods was assessed using Passing-Bablok and Bland-Altman plots.
  
  
  RESULTS
  GE were detected in all 3 breeds: 9/20 Greyhounds (45.0%), 10/29 Italian Greyhounds (34.5%), and 5/24 Whippets (62.5%) with no significant differences in the frequency of GE among the breeds. In samples containing GE, both analyzers underestimated the percentage of eosinophils and occasionally eosinophils were not detected at all. When a novel "GE gate" was used, the percentage of eosinophils reported by the Sysmex was similar to that obtained by manual counting.
  
  
  CONCLUSIONS
  GE are found in the blood of sighthounds other than Greyhounds. Hematology analyzers may underestimate the percentage of GE, probably due to their abnormal physical or chemical features. Underestimation is slight and usually clinically insignificant, but occasionally eosinophils are completely misclassified. Using the Sysmex analyzer, a GE gate can be designed to normalize the eosinophil count.
authors.affiliation: Departments of Veterinary Pathology, Hygiene and Public Health.
authors.forename: Luca
authors.initials: L
authors.lastname: Giori
authors.affiliation: Veterinary Clinical Sciences, University of Milan, Milan, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Gironi
authors.affiliation: Veterinary Clinical Sciences, University of Milan, Milan, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Scarpa
authors.affiliation: Centro Medico Veterinario, Castano Primo, Milan, Italy.
authors.forename: Angelo
authors.initials: A
authors.lastname: Anselmi
authors.affiliation: Veterinary Clinical Sciences, University of Milan, Milan, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Gualtieri
authors.affiliation: Departments of Veterinary Pathology, Hygiene and Public Health.
authors.forename: Saverio
authors.initials: S
authors.lastname: Paltrinieri
mesh_terms: D000818:Animals; D001773:Blood Cells / Q000166:cytology*; D004285:Dogs / Q000097:blood*; D004801:Eosine Yellowish-(YS); D004804:Eosinophils / Q000166:cytology*; D007958:Leukocyte Count / Q000295:instrumentation / Q000662:veterinary*; D008751:Methylene Blue; D012680:Sensitivity and Specificity
chemical_list: C043260:May-Grunwald Giemsa; D008751:Methylene Blue; D004801:Eosine Yellowish-(YS)