Evaluation of the LeukoScope for Point-of-Care Measurement of White Blood Cell and Neutrophil Counts in Malawi.

Abstract

White blood cell (WBC) and neutrophil counts are important laboratory tests used by clinicians to assess a variety of conditions. However, current methods to measure WBC and neutrophil counts are difficult to perform at the point of care, being either cost or labor prohibitive. To meet this need, we developed the LeukoScope: a portable, imaging-based system to measure WBC and neutrophil counts from a drop of blood. Here, we present the performance of the LeukoScope in 136 pediatric and 164 neonatal subjects at a central hospital in Malawi. For pediatric patients, 95.4, 66.7, and 80.0% of samples with normal, low, and high WBC counts, respectively, were correctly identified, and 88.6, 100.0, and 89.3% of samples with normal, low, and high neutrophil counts, respectively, were correctly identified. Accuracy was lower overall for neonatal samples; 92.1, 64.3, and 26.7% of samples with normal, low, and high WBC counts, respectively, were correctly identified, and 73.2 and 78.6% of samples with normal and high neutrophil counts, respectively, were correctly identified. Results of this study show that the LeukoScope can help meet need for point-of-care measurement of WBC counts in pediatric patients and highlight the challenges of point-of-care assessment of WBC counts in neonatal patients.