Multispectral Imaging for MicroChip Electrophoresis Enables Point-of-Care Newborn Hemoglobin Variant Screening

ABSTRACT Hemoglobin (Hb) disorders affect nearly 7% of the world’s population. Globally, around 400,000 babies are born annually with sickle cell disease (SCD), primarily in sub-Saharan Africa where morbidity and mortality rates are high. Although treatments are available for Hb disorders, screening, early diagnosis, and monitoring are not widely accessible due to technical challenges and cost, especially in low-and-middle-income countries. We hypothesized that multispectral imaging will allow sensitive hemoglobin variant identification in existing affordable paper-based Hb electrophoresis, which is a clinical standard test for Hb variant screening. To test this hypothesis, we developed the first integrated point-of-care multispectral Hb variant test: Gazelle-Multispectral. Here, we evaluated the accuracy of Gazelle-Multispectral for Hb variant newborn screening in 321 completed tests in subjects younger than 6 months with known hemoglobin variants including hemoglobin A (Hb A), hemoglobin F (Hb F), hemoglobin S (Hb S) and hemoglobin C (Hb C). Gazelle-multispectral detected levels of Hb A, Hb F, Hb S, and Hb C, demonstrated high correlations with the results reported by laboratory gold standard high performance liquid chromatography (HPLC) at Pearson Correlation Coefficient = 0.97, 0.97, 0.89, and 0.94. Gazelle-multispectral demonstrated 100% sensitivity and 100% specificity in both disease vs normal and disease vs trait, 98.1% sensitivity and 97.0% specificity in trait vs normal in comparison to HPLC in newborns. The ability to obtain rapid and accurate results on newborn samples suggest that Gazelle-Multispectral is suitable for large-scale newborn screening and potentially for accurate diagnosis of SCD in low resource settings.