Point-of-Care Newborn Screening for Sickle Cell Disease at Selected Health Facilities in the Gambia.

Abstract

Sickle cell disease (SCD) contributes significantly to childhood morbidity and mortality in sub-Saharan Africa. Early diagnosis through newborn screening (NBS) and subsequent comprehensive follow-up care will reduce the burden. Up till now, the prevalence of SCD among newborns remains unknown in The Gambia and there is no national NBS programme to address this significant public health issue. We assessed the real-time frequency of SCD in the country and determined differences in the pattern of SCD phenotypes among different ethnic groups. A preliminary prospective feasibility study was done in eight purposively selected hospitals in the seven Health Administrative Regions and Banjul. Consecutive newborn babies delivered or managed in these facilities were screened using HemoTypeSC, a sensitive and specific ELISA-based point-of-care test (POCT). Babies identified as SCD with HemoTypeSC were retested at age ≥6 months using alkaline cellulose acetate hemoglobin electrophoresis (ACAE). Head-to-head comparison between HemoType screening and gold standard HPLC could not be done. 1,168 newborn babies were screened from April 14 to August 12, 2023. Fifteen (1.3%) had homozygous HbS (HbSS), two (0.2%) heterozygous for HbS and HbC (HbSC), 204 (17.5%) had sickle cell trait (HbAS), four (0.3%) heterozygous for HbA and HbC (HbAC), and 943 (80.7%) had normal hemoglobin (HbAA). The 17 with SCD (HbSS and HbSC) comprised of 7 (2.2%) of 324 Fula; 6 (1.4%) of 426 Mandinka; 2 (1.6%) of 125 Jola and 2 (1.3%) of 150 Wolof. Fourteen (82.4%) of the 17 accepted the diagnosis and were enrolled into the SCD program. For these 14, HemoTypeSC had 100% sensitivity with ACAE when repeated at age ≥6 months. In addition to determining the real-time newborn prevalence of SCD and trait in The Gambia for the first time, this pilot study showed that SCD-POCT is feasible in Gambian health facilities.