Routine Screening for Sickle Cell Disease during Pregnancy: Epidemiological and Haemoglobin Profile in Congo

Area of Science:

• Genetics
• Hematology
• Public Health

Background:

• Sickle-cell disease is a prevalent genetic disorder in sub-Saharan Africa, inherited in an autosomal recessive pattern.
• Pregnancy screening for sickle-cell (S) gene carriers is crucial for identifying risks to the unborn child.
• Immuno-chromatographic tests are being promoted for sickle-cell screening.

Purpose of the Study:

• To establish the epidemiological profile of sickle-cell disease in pregnant women in Congo.
• To determine the performance of the Emmel test for sickle-cell screening.
• To assess the utility of immuno-chromatographic methods in this context.

Main Methods:

• An analytical cross-sectional study was conducted over three months in 12 departments of Congo.
• Pregnant women attending Antenatal Consultation (ANC) from 12 weeks of amenorrhea were included.
• Data collected included epidemiological variables, Emmel test results, and haemoglobin profiles.

Main Results:

• Out of 782 pregnant women screened, 27.88% had sickle-cell trait (AS) and 1.79% had sickle-cell disease (SS).
• Sickle-cell carriage varied significantly by department, with trait frequencies from 16.67% to 31.17% and homozygous frequencies from 0% to 66.67%.
• The Emmel test demonstrated 46% sensitivity and 99% specificity, with a positive predictive value (PPV) of 95% and a negative predictive value (NPV) of 81%.

Conclusions:

• Sickle-cell disease carriage is high among pregnant women in Congo, affecting younger, educated, and married individuals.
• The Emmel test has high specificity but limited sensitivity for detecting sickle-cell conditions in this population.
• Targeted screening and improved diagnostic tools are needed for effective management of sickle-cell disease in pregnant women.