Point-of-Care White Blood Cell Differential Testing in Pediatric Inpatients (2 Months-17 Years): How Does HemoScreen Perform?

BACKGROUND

Point-of-care (POC) hematology testing is of growing interest in pediatric practice. We previously evaluated an image-based POC hematology analyzer (HemoScreen, PixCell Medical, Yokneam Illit, Israel) for total white blood cell (WBC), red blood cell, and platelet counts and associated indices in pediatric inpatients. Given the diagnostic importance of WBC differentials, this study aimed to extend the evaluation to five-part differential counts.

METHODS

We prospectively analyzed 141 venous K2-EDTA samples from pediatric inpatients aged 2 months-17 years. Complete blood counts were obtained with the Sysmex XN-1000 (Sysmex Co., Kobe, Japan) and reanalyzed with HemoScreen. Blood smears were digitized with CellaVision DC-1 (CellaVision AB, Lund, Sweden) and reviewed by cytologists. HemoScreen WBC differential percentages were directly compared with cytologist-reviewed digital microscopy, whereas absolute counts were compared with composite values calculated from microscopy-derived percentages and the Sysmex WBC count. Analytical agreement, diagnostic concordance and flagging performance were assessed.

RESULTS

Of 141 samples, 138 were suitable for analysis. Correlations for WBC subsets were strong to excellent (ρ = 0.625-0.977). Mean bias was within or close to EFLM-derived acceptable limits for neutrophils and lymphocytes. Diagnostic agreement was excellent for neutropenia, neutrophilia, and lymphocytopenia, and good for lymphocytosis, monocytosis, and eosinophilia. HemoScreen flagged 31.9% of samples for abnormal cells, with sensitivity 74.1%, specificity 78.4%, positive predictive value 45.5%, negative predictive value 92.6%, and overall efficiency 77.5%.

CONCLUSIONS

In pediatric venous samples, HemoScreen showed good analytical and diagnostic performance for the five-part WBC differentials. Its abnormal-cell flagging may support prioritization of morphological review, although its workflow impact requires further evaluation.