Overview

• Immature, unsegmented neutrophils normally found circulating in small numbers.
• Assess numbers relative to mature neutrophil count:
  • Regenerative left shift: mature neutrophils Hematology: neutrophil outnumber bands and are elevated or normal.
  • Degenerative left shift: excessive neutophil consumption → bands and/or less mature leukocytes outnumber mature neutrophils.
• Neutrophils are short-lived (approximately 4 days).
• Recognized by classic U-shaped nucleus or nucleus with indentations <50% of the width of the nucleus. May see horseshoe or S-forms.

Sampling

Tests

Methodologies

• Manual hemocytometer - accuracy +/- 20%.
• Electronic counting systems - accuracy +/- 3-5% (intralaboratory); +/- 10-15% (interlaboratory).
• QBC-V ( quantitative Buffy Coat analysis) hematology system.

Availability

• Widely available at commercial laboratories.
• May be performed in practice.

Validity

Sensitivity

• Sensitive.

Specificity

• Non-specific.

Predictive value

• Useful if used in conjunction with differential white blood cell counts.

Technician (extrinsic) limitations

• Some experience is required for accurate identification of leukocytes.

Result Data

Further Reading

Publications

Refereed papers

• Recent references from VetMedResource and PubMed.

Other sources of information

• Cowell R L, Tyler R D & Meinkoth J H (1999) Diagnostic Cytology and Hematology of the Dog and Cat. 2nd edn. Mosby, USA.
• Duncan J R, Prasse K W & Mahaffy E A (1994) Veterinary Laboratory Medicine Clinical Pathology. 3rd edn. Iowa University Press, USA.
• Jain N C (1993) Essentials of Veterinary Hematology. Lea & Febiger, USA.