Clinical value of clinician‐ordered pathologist‐reviewed peripheral blood smears in a teaching hospital

Abstract Peripheral blood smear (PBS) review is a test performed to evaluate a wide variety of hematologic and non‐hematologic disorders. Evaluation of a peripheral smear by an expert permits assessment of blood cell morphology on a broad level. We aimed to evaluate the concordance between clinician orders and pathologist‐reported findings and to assess the diagnostic, normal, and informative categories. This study was a cross‐sectional analysis. Five hundred patients over a 3‐month period were included. Data collection included patient age, gender, ward, along with the clinical reason for PBS and the pathologist reading of the PBS. In this study, we classified the pathology report results into diagnostic, normal, and informative categories. We then evaluated the concordance between the clinicians' orders and the pathology reports; if at least one finding in the PBS result was matched with a clinician order, it was considered as concordance between the order and the PBS result. The most common cause of PBS order was WBC abnormalities (81.0%), followed by RBC (50.4%) and platelet abnormalities (41.4%). Pathologist evaluation showed 67.2% WBC abnormalities, 53.2% RBC abnormalities, and 44.2% had platelet abnormalities. Diagnostic findings were present in 13% of cases, while 79% were informative and 8% normal PBSs. Concordance between clinician orders and pathologist reports was found in 68.2% of cases. This study highlights the essential yet selective role of PBS in modern hematology, particularly in diagnosing WBC abnormalities and hematologic malignancies. While PBS offers significant informative value, especially for non‐neoplastic conditions like anemia and thrombocytopenia, its diagnostic contribution may be more limited. The concordance (68.2%) emphasizes the need for clearer criteria and targeted use to optimize resource utilization. Implementing standardized guidelines and leveraging technological advancements could enhance the efficiency and diagnostic impact of PBS in clinical practice.