The exploration of cell population data in clinical use: Beyond infectious diseases

Cell population data (CPD) is regarded as the fingerprint of a blood cell at a given moment. CPD parameters harbor information associated with cell morphology and can be automatically generated using modern hematological analyzers. Various studies have revealed many unique clinical applications for CPD, especially for infectious diseases, such as sepsis. For example, one monocyte-related CPD parameter is the monocyte distribution width (MDW), which can be generated using a Beckman Coulter hematological analyzer. MDW has received FDA and CE approval for aiding in sepsis diagnosis in adult patients in the emergency department. Additionally, MDW can serve as a diagnostic biomarker in patients infected with SARS-CoV-2. CPD has also been widely explored for possible clinical applications beyond infectious diseases, such as for predicting myelodysplastic syndromes, screening for hematological malignancies, and detecting sterile inflammation. CPD parameter measurements are easily obtained and quite cost-effective, making them practical for clinical use. However, there are some potential drawbacks of CPD parameters. Some pre-analytical conditions can affect CPD values. Furthermore, CPD are specific to certain hematological analyzers and the result cannot be transferred between different analyzers. The practical usefulness of CPD reference intervals is also still questionable. In this review, wesummarize the current studies related to CPD and its clinical applications. Additional well-designed clinical studies related to CPD are still expected.