Diagnostic accuracy of the sickle SCAN® rapid test for neonatal screening of sickle cell disease in Lubumbashi, Democratic Republic of the Congo

Abstract

Sickle cell disease (SCD) is a common and potentially life-threatening haematological disorder. In high-income countries, universal newborn screening and timely interventions have markedly reduced infant mortality. In contrast, in low-resource settings, diagnosis often occurs only in late childhood, once clinical manifestations have developed. The high cost, technical complexity, and limited availability of conventional diagnostic methods remain major barriers to implementing neonatal screening programmes in sub-Saharan Africa and other resource-constrained regions. We assessed the diagnostic performance of Sickle SCAN®, a prototype rapid immunoassay designed to qualitatively detect HbA, HbS, and HbC. The test is based on a lateral flow immunoassay format and provides results at the point of care. Cord blood samples from 365 newborns were analysed with Sickle SCAN® and results were compared against the reference standard of capillary electrophoresis. Sickle SCAN® accurately identified haemoglobin phenotypes in 97.3% of cases (95% CI: 95.0%-98.7%). For HbAA, sensitivity was 97.8% (95% CI: 94.9%-99.3%) and specificity was 96.5% (95% CI: 92.0%-98.9%). For HbAS, sensitivity was 95.8% (95% CI: 90.5%-98.6%) and specificity 98.0% (95% CI: 95.3%-99.3%). Importantly, no false-positive or false-negative results were observed for HbSS and HbAC, yielding 100% sensitivity and specificity for these phenotypes. Our findings demonstrate that Sickle SCAN® is a highly accurate, rapid, and low-cost tool for neonatal SCD screening. Its use could substantially reduce diagnostic delays, lower programme costs, and improve accessibility to early detection in resource-limited settings, thereby contributing to improved child survival.