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Evaluation of a Point-of-Care Testing Analyzer for Measuring Peripheral Blood Leukocytes
Published on: March 22, 2022
The evaluation of leukocytosis
Clay W Walker1, Thomas Hartman, Manuel Pompa
1Clay W. Walker is an assistant professor of PA studies and director of didactic education in the PA program at A.T. Still University in Mesa, AZ, and is an assistant professor of family medicine at Mayo Clinic in Phoenix, AZ. Thomas Hartman is an associate professor in the Department of Physician Assistant Studies and director of student progression and retention for the PA program at A.T. Still University. Manuel Pompa practices in the Department of Family Medicine at Mayo Clinic. C. Walker discloses service as an external clinical expert on the GlaxoSmithKline UTI Consultancy Panel and as a mentor for PAs and NPs in clinical practice through Medgeeks. The authors have disclosed no other potential conflicts of interest, financial or otherwise.
Leukocytosis, defined as an elevated white blood cell count, is a frequently encountered laboratory finding with a broad differential diagnosis ranging from transient reactive processes to life-threatening hematologic malignancies. Distinct patterns of elevation can provide valuable diagnostic clues that narrow the differential diagnosis and guide next steps. This article outlines a systematic approach to evaluating leukocytosis, emphasizing integration of clinical history, physical examination, and laboratory data. The discussion highlights both nonmalignant and malignant causes, including acute and chronic leukemias, lymphomas, and myeloproliferative disorders, and offers guidance on when to pursue advanced diagnostics. Finally, a practical evaluation algorithm is included to support clinical decision-making. By recognizing key clinical features, laboratory patterns, and risk factors associated with malignancy, clinicians can appropriately triage patients for specialist referral and ensure timely intervention.
Leukocytosis, defined as an elevated white blood cell count, is a frequently encountered laboratory finding with a broad differential diagnosis ranging from transient reactive processes to life-threatening hematologic malignancies. Distinct patterns of elevation can provide valuable diagnostic clues that narrow the differential diagnosis and guide next steps. This article outlines a systematic approach to evaluating leukocytosis, emphasizing integration of clinical history, physical examination, and laboratory data. The discussion highlights both nonmalignant and malignant causes, including acute and chronic leukemias, lymphomas, and myeloproliferative disorders, and offers guidance on when to pursue advanced diagnostics. Finally, a practical evaluation algorithm is included to support clinical decision-making. By recognizing key clinical features, laboratory patterns, and risk factors associated with malignancy, clinicians can appropriately triage patients for specialist referral and ensure timely intervention.
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