Evaluation of Umbilical Artery Doppler Indices in Pregnant Women With Sickle Cell Anemia Disease at a Nigerian Tertiary Hospital

Abstract

Sickle cell disease (SCD) and its variants are genetic disorders resulting from the presence of a mutated form of hemoglobin, hemoglobin S (HbS). 1 The prototype of these diseases is sickle cell anemia, an autosomal recessive disorder, which results from point mutation and leads to substitution of valine for glutamic acid, at the sixth position of the beta-globin chain. The resultant hemoglobin molecule has abnormal physiochemical properties that lead to the manifestation of the chronic disease state. 2 SCD affects 20 to 25 million people globally. 3 The exact prevalence is unknown in the United States, 4 but a study by Brousseau et al. 5 on the number of people with SCD in the United States showed 89,079 people in 2005. Prevalence in India varies per tribe from 1% to 40%, with Madhya Pradesh having the highest load with an estimated number of 961,492 heterozygotes and 67,861 homozygotes. 6 In Nigeria, by far the most populous country in sub-Saharan Africa, 24% of the population are carriers of the mutant gene, and the prevalence of sickle cell anemia is 20 per 1000 births. 3 This would indicate that in Nigeria alone, 150,000 children are born with sickle cell anemia every year. 7 The pathophysiology of sickle cell anemia is based on the distortion of red blood cells when these circulate through areas of low oxygen tension. With time, the cells become irreversibly sickled and are either removed from 791157J DMXXX10.

Prognostic accuracy of antenatal Doppler ultrasound for adverse perinatal outcomes in low-income and middle-income countries: a systematic review

“…Twenty studies evaluated the UA,10–29 and seven reported its predictive values for FGR. The PPV for FGR reported in the individual studies were between 77.40 and 88.5,11 16 21 24 while the area under the receiver operating characteristic (AU ROC) curve was 0.63,17 mostly in high-risk pregnancies. The NPV ranged from 55.4 to 95.65 11 16 21 24.…”

“…The NPV ranged from 55.4 to 95.65 11 16 21 24. FGR was defined as birth weight or abdominal circumference below the 10th percentile in two studies,11 17 ponderal index less than 10 in one study,21 and was not defined in the remaining studies 16 24 26. Increased flow impedance in the UA had PPV for composite adverse outcomes between 66.60 and 96.6 in high-risk pregnancies 11 13 19 23.…”