Precision and accuracy of absolute lymphocyte counts.

Area of Science:

• Clinical laboratory science
• Hematology
• Immunology

Background:

• Automated hematology instruments are widely used for leukocyte counting.
• Accurate leukocyte counts are essential for various diagnostic purposes, including CD4 determinations.
• Preanalytical variables can significantly impact the accuracy of automated cell counts.

Purpose of the Study:

• To critique the accuracy of leukocyte counting using automated hematology instruments.
• To identify critical preanalytical variables affecting leukocyte counts.
• To establish criteria for selecting suitable laboratories for CD4 determination-related lymphocyte counts.

Main Methods:

• Review of existing literature and best practices in hematology.
• Analysis of preanalytical factors influencing automated leukocyte counts.
• Development of selection criteria for specialized laboratory services.

Main Results:

• Preanalytical variables such as anticoagulant type and specimen assay delays are critical.
• The precision of leukocyte counts is directly proportional to the total number of leukocytes counted.
• Specific criteria for laboratory selection for CD4 determinations are proposed.

Conclusions:

• Optimizing preanalytical conditions is vital for reliable automated leukocyte counting.
• Laboratory selection is a key factor in ensuring the quality of lymphocyte counts for CD4 determinations.
• Standardized criteria can improve the consistency and accuracy of diagnostic testing.