Practical Considerations in the Implementation of Peripheral Smear Review in the Clinical Laboratory

Area of Science:

• Hematology
• Clinical Pathology
• Laboratory Medicine

Background:

• Automated hematology analyzers are standard, but visual peripheral blood smear (PBS) review remains essential for specific cases.
• Existing guidelines for PBS review, like those from the International Consensus Group for Hematology Review (ICGHR), have knowledge gaps regarding practical implementation.
• An international working group (Peripheral Smear Review Working Group [PSRWG]) identified the need for updated guidance.

Purpose of the Study:

• To provide practical guidance and considerations for the selection and implementation of visual peripheral blood smear (PBS) review criteria in clinical laboratories.
• To address knowledge gaps concerning the application of PBS review in the context of modern hematology analyzers.
• To expand upon existing ICGHR rules with practical implementation insights.

Main Methods:

• The article was developed by an international working group (PSRWG).
• It outlines indications for PBS review, including automated analyzer flags (system, suspect, numerical/definitive) and delta checks.
• It details a multistep validation process for PBS review criteria, including defining positive findings, specimen selection, slide review methods, and statistical approaches.

Main Results:

• Practical examples and explanations are provided for various PBS review indications and flag modification.
• Pragmatic approaches and key considerations for each step of the validation process are discussed.
• The importance of tailoring PBS visual review workflows to specific clinical laboratory needs, accrediting agencies, infrastructure, and patient populations is emphasized.

Conclusions:

• Visual peripheral blood smear (PBS) review, guided by practical considerations, remains a vital component of hematological analysis.
• Implementing standardized yet adaptable PBS review criteria is key to optimizing laboratory diagnostics.
• This guidance aims to bridge knowledge gaps and enhance the effective use of PBS review in clinical settings.