ISSN 2997-1036
International Journal of Hematology | Vol. 9, No. 4, April 2018 | pp. 25–32
DOI: 10.46882/2018/IJH/000100
Short Communication
Title: Evaluation of automated white blood cell precursor flagging efficiency on a five-part differential cell counter in acute sepsis
Names of Authors: B. C. Akpan¹, D. E. Usman²
Authors’ Affiliations: ¹Department of Haematology, University of Calabar, Calabar, Nigeria; ²Department of Clinical Pharmacology, Ahmadu Bello University, Zaria, Nigeria
Abstract: Severe systemic bacterial infections trigger acute bone marrow left shifts, resulting in the release of immature granulocytic precursors that can generate automated cell counter flags. This operational study evaluated the flagging efficiency and positive predictive value of an automated immature granulocyte (IG) flag parameter on a five-part differential cell counter in 120 intensive care patients suspected of having acute sepsis. Automated results were cross-validated against manual visual peripheral blood smear differential counts. True immature granulocytic lines (metamyelocytes, myelocytes) were microscopically confirmed in 75.8% (91 of 120) of the flagged samples. The automated cell counter achieved a sensitivity of 91.2% and a false-positive rate of 14.2%, with misclassifications occurring primarily in specimens containing highly reactive atypical lymphocytes. An absolute immature granulocyte count exceeding 0.45 × 10⁹/L correlated strongly with positive blood culture matrices. Utilizing automated precursor flags offers a fast, low-cost screening tool that alerts clinicians to prominent marrow left shifts during acute infective stress.
Keywords: Immature granulocytes, automated cell counter, left shift, sepsis screening, peripheral blood film
Manuscript Timeline: Received: January 15, 2018; Revised: February 20, 2018; Accepted: March 11, 2018; Published: April 14, 2018