RESUMO
Sickle-cell disease, a genetic condition with a high prevalence in sub-Saharan Africa, is transmitted in an autosomal recessive mode. Its screening during pregnancy makes it possible to identify carriers of the S gene which constitute a risk for the unborn child. In order to promote the use of immuno-chromatographic tests, we have set ourselves the task of establishing the epidemiological profile and determining the Emmel test performance. Analytical cross-sectional study of three months duration carried out in the 12 departments of Congo in pregnant women, from 12 weeks of amenorrhea, Admitted for Antenatal Consultation (ANC). The studied variables were epidemiological, Emmel test and immuno-chromatographic profile of haemoglobin. 782 pregnant women screened, of which 27.88% were AS sickle cell trait and 1.79% homozygous SS. The median age of sickle cell patients was 29 years vs. 25 years (p=0.10). High education level, married status, history of transfusion and sickle cell disease, and high ANC number were more common in pregnant sickle cell patients (p<0.05).The frequency of sickle cell trait ranged from 16.67 to 31.17% and homozygous forms from 0 to 66.67% depending on the department. The sensitivity and specificity of the Emmel test were 46% and 99% with PPV and NPV of 95% and 81% respectively. Sickle cell disease carriage, which is high in both forms, is more often of interest to young, educated, married pregnant women and follow-up by health personnel other than the doctor in rural areas.
RESUMO
INTRODUCTION: Sickle cell disease is an autosomal recessive inherited disorder due to the mutation of a gene coding for the globin beta chain. The aim of this study is to update the epidemiological data on hemoglobinoses, in particular sickle cell disease in newborns in Congo. MATERIALS AND METHODS: This was a descriptive cross-sectional study, conducted from October 1, 2019, to March 31, 2020, throughout the Congolese national territory. It involved all full-term newborns, without distinction of nationality, aged 5 days or less, and whose parents consented to participate in the study. The blood samples, taken at the heel and collected on Whatman blotting paper, were analyzed using the HPLC Variant NBS machine. RESULTS: In 2897 newborns (NN) screened, hemoglobin abnormalities were found in 603 NN (20.81%). The mean age of these newborns was 1 day (extremes 0 and 5 days). The male-to-female ratio was 1.03. Abnormal hemoglobins were mainly Hb S (n = 597 (97.71%)); Hb C (n = 5 (0.82%)); and variants (n = 7 (1.15%)). The national prevalence of major sickle cell (MSC) syndromes and sickle cell trait was 1.35% and 19.43%, respectively. The prevalence ranged from 1.77% to 2.56% for MSS in four departments and from 20.5% to 25.8% for the sickle cell trait in six other departments. CONCLUSION: Data on homozygous sickle cell disease remain consistent with previous studies. However, further studies should clarify the molecular anomalies of the variants observed in our samples.