Enhancing Newborn and Early Childhood Sickle Cell Disease Screening in Nigeria Using Gazelle® a Novel Microchip Electrophoresis Platform
Arwa Fraiwan, Bernard Ebruke, Jibril Binta, Grace Olanipekun, Priya Thota, Umut Gurkan, Stephen ObaroAbstract
Background
Sickle Cell Disease (SCD) mutation afflicts millions of people worldwide and is associated with considerable morbidity and mortality. Nigeria has the world’s largest cohort of SCD patients, it is estimated that about 150,000 babies are born annually in Nigeria with sickle cell disease (SCD) and over half of these children do not survive beyond their fifth birthday. Given the high prevalence of the sickle hemoglobin (HbS) gene and the large population of affected children, high infant and under-5 mortality, it is estimated that SCD contributes at least 6% of all childhood mortality and of those affected, only 10% in sub–Saharan Africa (SSA) are likely to reach adolescence. In high-income countries the implementation of universal newborn screening has enabled the development of effective strategies for the management and treatment of SCD and its comorbidities, leading to improved survival rates and quality of life. In low-resource settings, point-of-care diagnostic platforms can significantly improve access to diagnosis and empower screening programs for newborns and young children.
Methods
In this study we report the results of SCD screening of Nigerian children using Gazelle®, a novel paper-based microchip electrophoresis point-of-care platform for hemoglobin disorder testing. Gazelle® is an affordable, battery-powered reader equipped with GPS, Wi-Fi and Bluetooth capabilities suitable for use in clinics and remote settings. An integrated on-board application performs quality checks, automatically interprets results, and displays quantitative hemoglobin levels. Up to 1,000 test results can be stored on the reader, or be be printed, saved as PDF files, or securely transmitted to a cloud-based information system for long-term storage. Institutional review board approval was obtained from selected tertiary hospitals in Kano, City. Blood samples were collected from 996 subjects under 2 years of age, and none of the subjects had a known hemoglobinopathy status. Gazelle testing was performed at the International Foundation Against Infections disease in Nigeria (IFAIN) satellite lab in Kano, while confirmatory HPLC testing was done at IFAIN central lab in Abuja.
Results
The study population included 162 neonates (0 – 30 days, 53.1% females, and 46.9% males), 145 newborns (2 – 6 months, 46.9% females, and 53.1% males), and 689 infants (6 months – 2 years, 43.5% females, and 56.5% males). Tests were performed by local staff including healthcare workers and clinical laboratory personnel, after receiving a short training on the use of the Gazelle® platform. Moreover, reference test results were not provided for the Gazelle® platform users, and Gazelle® results were not available to those performing the HPLC tests. Statistical analyses of the Gazelle® test results included sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for normal vs. disease, normal vs. trait, and trait vs. disease states. The results detailed in Table 1 demonstrate outstanding levels of agreement between Gazelle results and those obtained from HPLC.
Conclusions
In summary, the findings of this study demonstrate the potential of the Gazelle® diagnostic platform to strengthen national screening programs, especially in areas with a high prevalence of SCD and limited availability of standard diagnostic tools. Its user-friendly operation, portability and reliable performance offer a solution to major challenges in hemoglobinopathy screening and may broaden access to timely, life-saving care.