Preliminary Evaluation of a Point-of-Care Testing Device (SickleSCAN™) in Screening for Sickle Cell Disease

Abstract

Sickle cell disease affects about 150,000 births annually in Nigeria. Early diagnosis is hampered by factors such as centralized and urban localization of laboratories, high cost of diagnostic equipment and inadequate skilled manpower to operate them. The need for a low-cost, portable, easy-to-use diagnostic test for sickle cell disease is critical, especially in resource-poor countries. In this study, we evaluated the performance characteristics of a novel point-of-care testing device (SickleSCAN™), and its acceptability and feasibility, as a possible screening tool for sickle cell disease. In the first phase, we assessed the performance characteristics of SickleSCAN™ by evaluating 57 subjects comprising both children and adults attending a primary health center, for Hb SS (β^S/β^S; HBB: c.20A>T), Hb SC (β^S/β^C; HBB: c.19G>A) and Hb AS (β^A/β^S) using SickleSCAN™, cellulose acetate electrophoresis (CAE) and high performance liquid chromatography (HPLC). Performance characteristics such as diagnostic sensitivity and specificity were compared to HPLC as a standard method. We subsequently undertook a second phase wherein the acceptability and feasibility of the device for sickle cell disease screening, was evaluated using semi-structured and structured questionnaires among 197 healthcare personnel and 221 subjects, respectively. Sickle cell disease was carried by 3.4% of the subjects. The diagnostic sensitivity, specificity and test efficiency of SickleSCAN™ for sickle cell disease (Hb SS and Hb SC), were 100.0, 98.2 and 98.2%, respectively. Findings from this study showed SickleSCAN™ to be a viable screening tool that can easily be applied in community-based screening for early diagnosis of sickle cell disease with little expertise and low cost.

Keywords: Point-of-care; screening; sensitivity; sickle cell disease; specificity.