Today's automated hematology analyzers capable of performing a full CBC and a differential leukocyte count (DLC) on whole blood, particularly in a closed tube system, using cytochemistry or impedance-based flow cytometry technology coupled with laser light scattering, conductivity and/or differential cell lysis, are here to stay. Their need and popularity among at least the large, cost and quality-conscious clinical laboratories have been growing for the past few years and will continue to do so in the years ahead. The efficiency and reliability of several of these analyzers in performing complete CBCD (CBC and DLC) and in flagging significant abnormalities have been tested and found acceptable with the need to review a stained blood smear or perform a manual DLC to confirm or obtain additional information on selected cases.
Automation ; Human ; Leukocyte Count/*methods

A microscopic examination of an appropriately prepared and well-stained blood smear by a knowledgeable laboratory professional is necessary and clinically useful in a number of circumstances and for a variety of reasons. In this article, an attempt is made to delineate the purpose and criteria for blood smear examination in a variety of circumstances that are encountered in everyday laboratory hematology practice. A blood smear scan serves to at least (a) verify the flagged automated hematology results and (b) determine if a manual differential leukocyte count needs to be performed. Blood smear examination/manual differential leukocyte count with complete blood count (CBC) provides the complete hematologic picture of the case, at least from the morphologic standpoint. Blood smear review with or without interpretation serves to ensure that no clinically significant finding is missed, besides providing diagnosis or diagnostic clue(s), particularly if and when interpreted by a physician.
Blood Cell Count ; Hematologic Tests/*methods ; Humans ; Leukocyte Count ; Leukocytes/cytology ; Medical Laboratory Personnel/standards