Livingstone Gayus Dogara

The Consortium on Newborn Screening in Africa (CONSA), launched by the American Society of Hematology in 2020, is designed to initiate and expand sustainable newborn screening (NBS) programs for sickle cell disease (SCD) across sub-Saharan Africa. This multiyear pilot program includes 11 clinical sites in 7 countries, namely Ghana, Kenya, Liberia, Nigeria, Tanzania, Uganda, and Zambia. After extensive training of laboratory and clinical personnel, dried blood spots were collected from newborns and tested by isoelectric focusing at central laboratories within each country. Positive samples were confirmed, and the affected infants were invited into clinical care for penicillin prophylaxis, malaria prevention, routine immunizations, and family education. As of November 2025, almost 175 000 samples have been collected and assessed. The overall prevalence of SCD was 1.46%, with the highest prevalence in Mwanza, Tanzania (2.00%). The majority of positive screening results were homozygous HbSS (81.5%), along with compound heterozygous HbSC (11.0%) and HbSβ+ thalassemia (7.5%). Hemoglobin S trait was common throughout the countries with an average of 16.17%, whereas hemoglobin C trait had an incidence of 1.59% and was found primarily in Ghana and Nigeria. Additional hemoglobin variants were also detected in several countries. Confirmatory samples have been documented in about one-third of infants with a positive screening result, with 87.8% of those confirmed to have SCD. Fewer than half of the affected infants have documented clinical follow-up at CONSA sites for various logistical and financial reasons. CONSA has made great strides in promoting NBS for SCD in sub-Saharan Africa, but gaps in the confirmatory testing and enrollment into clinical care persist.

Sickle cell disease (SCD) is a common condition within sub-Saharan Africa and associated with high under-5 mortality (U5M). The American Society of Hematology instituted the Consortium on Newborn Screening in Africa (CONSA) for SCD, a 7-country network of sites to implement standardized newborn hemoglobinopathy screening and early intervention for children with SCD in sub-Saharan Africa. CONSA’s overall hypothesis is that early infant SCD screening and entry into standardized, continuous care will reduce U5M compared with historical estimates in the region. Primary trial objectives are to determine the population-based birth incidence of SCD and effectiveness of early standardized care for preventing early mortality consortium-wide at each country’s site(s). Secondary objectives are to establish universal screening and early interventions for SCD within clinical networks of CONSA partners and assess trial implementation. Outcomes will be evaluated from data collected using a shared patient registry. Standardized trial procedures will be implemented among designated birth populations in 7 African countries whose programs met eligibility criteria. Treatment protocol includes administering antibacterial and antimalarial prophylaxis and standard childhood vaccinations against infections commonly affecting children with SCD. Infants with a positive screen and confirmation of SCD within the catchment areas defined by each consortium partner will be enrolled in the clinical intervention protocol and followed regularly until age of 5 years. Effectiveness of these early interventions, along with culturally appropriate family education and counseling, will be evaluated by comparing U5M in the enrolled cohort to estimated preprogram data. Here, we describe the methodology planned for this trial.

The impact of socio-economic status on the risk of allergy in African children is not clear.This was a cross sectional study including children aged 6–14 years from urban and rural settings in north-central Nigeria. Participants underwent skin prick tests to house dust mite (HDM) and an interview investigating socio-economic status through the Family Affluence Scale (FAS) based on a score of 0–6.A total of 346 children were enrolled (52.8% boys; mean age ± SD 9.6 ± 2.0 years), including 142 (41% of total) rural and 204 (59% of total) urban pupils. Prevalence of HDM sensitivity was 2.8% (4/142) in the rural setting and 15.6% (32/204) in the urban setting (P < 0.001). Among urban children, frequency of HDM sensitization was 8.6% (7/81) in the lowest socio-economic group (FAS 0–1), 13.1% (8/61) in the intermediate one (FAS 2–3) and 27.4% (17/62) in the highest one (FAS ≥ 4).Urbanization and increasing wealth are associated with a higher frequency of sensitization to HDM in Nigerian children.

Introduction: Lung function abnormalities are common in sickle cell anaemia (SCA) but data from sub-Saharan Africa are limited. We hypothesised that children with SCA from West Africa had worse lung function than their counterparts from Europe.Methods: This prospective cross-sectional study evaluated spirometry and anthropometry in black African individuals with SCA (haemoglobin phenotype SS) aged 6–18 years from Nigeria and the UK, when clinically stable. Age-matched controls were also included in Nigeria to validate the Global Lung Initiative spirometry reference values.Results: Nigerian SCA patients (n=154) had significant reductions in both FEV₁ and FVC of ~1 z-score compared with local controls (n=364) and ~0.5 z-scores compared with the UK patients (n=101). Wasting (body mass index z-score<−2) had a prevalence of 27% in Nigerian patients and 7% in the UK ones (p1/FVC≥−1.64).Conclusions: This study showed that chronic respiratory impairment is more severe in children with SCA from West Africa than Europe. Our findings suggest the utility of implementing respiratory assessment in African children with SCA to early identify those with chronic lung injury, eligible for closer follow-up and more aggressive therapies.

Low hemoglobin (Hb) level at steady state in subjects with sickle cell anemia (SCA) may indicate severe chronic hemolysis and might be related to a more severe course of disease. In this study we investigated the hypothesis that low hemoglobin at steady state may be associated with higher rate of lung function impairment in children and adolescents with SCA. Methods In this cross-sectional study black African subjects with SCA (Hb phenotype SS) aged 6 to 18 years followed at the Barau Dikko Teaching Hospital, Kaduna, Nigeria, underwent spirometry and anthropometry measures. A recent Hemoglobin level at steady state was recorded for each patient. Caregivers or patients were interviewed through a questionnaire investigating a history of asthma or acute chest syndrome (ACS) and frequency of pain crises in the last year that required analgesics for at least 24 hours. Exclusion criteria were: the lack of recorded complete blood count (CBC) performed in the last 6 months, respiratory symptoms or feeling unwell on the test day, SCA-related acute events (e.g., pain crises) in the last two weeks or a blood transfusion or an ACS episode in the last month. A portable Easy-on-PC spirometer (ndd, Zurich, Switzerland) was used. Data were included if at least two forced expiratory manoeuvres met the ATS/ERS acceptability and repeatability criteria adapted for children (Miller MR, ERJ 2005; Kirkby J, Pediatr.Pulmonol.2008). Spirometry z-scores and percentage of predicted for FEV₁, FVC and FEV₁/FVC were derived according to the GLI-2012 reference equations for African Americans (Quanjer PH, ERJ2012). Spirometry patterns were classified as normal, obstructive (zFVC ≥ 1.64 + zFEV1/FVC < -1.64), restrictive (zFVC < -1.64 + zFEV1/FVC ≥ -1.64) or mixed (zFVC < -1.64 + zFEV1/FVC < -1.64) and a FEV₁ < 70% of predicted was considered indicative of lung end-organ disease (Kassim AA et al, Blood. 2015 Sep 24;126(13):1544-50). Group comparison between patients with Hb level < 7.5 g/dL versus Hb ≥7.5 g/dL were tested using unpaired t test, χ² or Fisher's exact test as appropriate. The relationship between Hb values and spirometry outcomes was explored through logistic and linear regression models. P-value < 0.05 was adopted as representing a statistically significant difference. Analyses were conducted using the software STATA and Graphpad Prism 7. Results A total of 186 subjects with SCA were initially enrolled. Only one child was on hydroxyurea. After exclusions, data from 126 patients (mean ± SD age of 11.5 ± 3.1 yr., 53% boys) were retained for the final analysis. Mean ± SD Hb value was 7.8±0.9 g/dL (range 5.6 to 10.9). Frequency of low Hb (< 7.5 g/dL) at steady state was 30.9% (39/126). Mean FEV₁ and FVC z-scores were lower and frequency of FEV₁ < 70% of predicted was higher in patients in the low Hb group compared to those with Hb ≥7.5 g/dL though differences were not statistically significant (table 1). Prevalence of restrictive spirometry pattern, possibly suggesting restrictive lung disease, was significant higher in patients with Hb level < 7.5 g/dL (17/39, 43.5%) than in those with Hb ≥7.5 g/dL (20/87, 22.9%) (p = 0.01; table 1). The odds ratio for restrictive spirometry pattern in presence of Hb level p = 0.03). In a linear regression model (figure 1) the FVC z-score resulted significantly related to the Hb level with an increase of 0.17 z-scores for each point of Hb (95% CI 0.01 to 0.34, p = 0.04; R² = 0.03). Frequency of asthma, pain crises and previous acute chest syndrome did was similar between the two groups (data not showed) Conclusions In Nigerian pediatric patients with sickle cell anemia a hemoglobin level < 7.5 g/dL at steady state was associated with a 2.5 higher risk of presenting a restrictive spirometry pattern and with a higher frequency of end-organ lung disease (FEV1 < 70% of predicted). Low hemoglobin levels in wellbeing may depend on intense chronic haemolysis that could worsen microangiopathy, inflammation and ischemia and reperfusion injury in the lungs, potentially determining a precocious onset of restrictive lung disease. These preliminary data seem to indicate that a low Hb level at steady state in African pediatric patients with sickle cell anemia is associated with more severe lung impairment and should prompt respiratory assessment with lung function when found.