Unreliable Automated Complete Blood Count Results: Causes, Recognition, and Resolution

Abstract

Automated hematology analyzers generate accurate complete blood counts (CBC) results on nearly all specimens. However, every laboratory encounters, at times, some specimens that yield no or inaccurate result(s) for one or more CBC parameters even when the analyzer is functioning properly and the manufacturer’s instructions are followed to the letter. Inaccurate results, which may adversely affect patient care, are clinically unreliable and require the attention of laboratory professionals. Laboratory professionals must recognize unreliable results, determine the possible cause(s), and be acquainted with the ways to obtain reliable results on such specimens. We present a concise overview of the known causes of unreliable automated CBC results, ways to recognize them, and means commonly utilized to obtain reliable results. Some examples of unreliable automated CBC results are also illustrated. Pertinent analyzer-specific information can be found in the manufacturers’ operating manuals.

Obtaining Reliable CBC Results in Clinical Laboratories

“…Given the importance of the CBC, numerous review articles, book chapters, and case reports have been published on the erroneous results of various CBC parameters, and a myriad of new information is being reported [6][7][8][9][10]. In their review article in this issue, Gulati, et al [11] provide an overview of how to recognize unreliable CBC results, how to identify the potential underlying causes, and ways to obtain reliable results. The authors present essential and up-to-date knowledge in a concise manner.…”

“…In their review article in this issue, Gulati, et al . [ 11 ] provide an overview of how to recognize unreliable CBC results, how to identify the potential underlying causes, and ways to obtain reliable results. The authors present essential and up-to-date knowledge in a concise manner.…”

“…Known causes of unreliable CBC results are grouped as interfering substances and abnormal cells or cellular phenomena [ 11 ]. Several methods of recognizing unreliable CBC results are described, including automated or manual review of analyzer-generated flags, delta check failures, review based on expectation or predefined quality control rules, visual inspection of the blood specimen tube, and blood smear examination [ 11 ].…”

“…Several methods of recognizing unreliable CBC results are described, including automated or manual review of analyzer-generated flags, delta check failures, review based on expectation or predefined quality control rules, visual inspection of the blood specimen tube, and blood smear examination [ 11 ]. Detailed examples of unreliable automated CBC results and methods for obtaining reliable results are provided for each listed cause; for interfering substances: lipemia, hemolysis, hyperbilirubinemia, red cell agglutinins, white cell agglutinins, platelet agglutinins, hyperproteinemia/paraproteinemia, cryoproteinemia, organisms, hyperglycemia, adipose tissue fragments/flat globules, fibrin clumps, small clots in the specimen tube; and for abnormal cells or cellular phenomena: red cell fragments/schistocytes, extremely microcytic red cells, lysis-resistant red cells, hyperleukocytosis, giant platelets, cytoplasmic fragments of leukocytes, platelet satellitosis, nucleated red blood cells, megakaryocytes, and non-hematopoietic cells [ 11 ]. For each example, a general description, the impact on CBC parameters, methods for recognizing unreliable results, methods for obtaining reliable results encompassing multiple approaches, including sample processing and calculational methods, and example cases with initial and re-run CBC results are described in detail based on the literature or the authors’ experiences.…”

Optimizing the management of analytical interferences affecting red blood cells on XN‐10 (Sysmex®)

“…Several sources of interferences are well-recognized: plasma changes (due to hemolysis, lipemia, icteric plasma, or immunoglobulins), haemoglobin or red blood cells disorders, leukocytosis. [1][2][3][4][5][6][7] With the development of new generation analyzers, novel technologies and parameters have been introduced to improve both analytical performances and detection of presumed interferences.…”