Purpose and Criteria for Blood Smear Scan, Blood Smear Examination, and Blood Smear Review

Abstract

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.

Validation rules for blood smear revision after automated hematological testing using Mindray CAL-8000

“…Due to the constant increasing of automation and shortage of skilled personnel, the OM review of blood smears has become a challenging issue for the organization of modern clinical laboratories, which are forced to analyze large volumes of samples in short time, with high accuracy and minimizing the risk of producing false negative results . The appropriate use of automated hematology hence requires the accurate knowledge and evaluation of both sensitivity and specificity of the technology, as well as of the algorithms and rules for blood smear review.…”

Rapid drug detection in whole blood droplets using a desorption electrospray ionization static profiling approach – a proof‐of‐concept

“…The use of glass slides for DESI profiling of blood samples leaves the opportunity to combine it with hematological expertise. Indeed, blood smears on glass slides are often used for hematological evaluation . Although even lower volumes can be found over the surface of blood smears, DESI static profiling could be considered for the analysis of these sample types.…”

Transfusion‐transmitted malaria masquerading as sickle cell crisis with multisystem organ failure

“…This in combination with the use of an automated hematology analyzer, which is typical in US hospitals and can miss the presence of parasites, delayed the diagnosis. The manual blood smear effectively narrowed the differential diagnosis to Plasmodium or Babesia infection, highlighting the clinical utility and diagnostic clues a simple blood smear provides . Additional laboratory data in combination with the patient's Duffy‐null RBC phenotype and clinical severity suggested P. falciparum as the most likely species.…”