Читать книгу Protocols for High-Risk Pregnancies - Группа авторов - Страница 136

Sickle cell disease (SCD) is a hemoglobinopathy caused by a single nucleotide substitution leading to abnormal hemoglobin structure. The abnormal shaped, “sickled,” red blood cells then create occlusion of the microvasculature, leading to painful crisis. These crises lead to hospitalizations, decreased quality of life, organ damage, and overall morbidity/mortality. The most significant form of the disease is HgbS‐S (sickle cell anemia). Other compound heterozygous conditions including HgbS‐C and HgbS‐beta‐thalassemia can produce similar, though often less severe clinical disease. Complications of SCD include infection, anemia, and infarction/vasoocclusion which can affect numerous organ systems including renal, cardiopulmonary, and vascular. Major complications associated with SCD include acute chest syndrome, pulmonary hypertension, stroke, renal disease, venous thrombotic events, and osteonecrosis. Patients with SCD are functionally asplenic and therefore are at risk of infections from Streptococcus pneumoniae and Haemophilus influenzae.

In pregnancy, SCD has been associated with adverse outcomes including small for gestational age neonates, pregnancy loss, preeclampsia, and maternal mortality. In the US, 1 in 12 African Americans has sickle cell trait (Hgb A‐S). Among African American newborns, 1 in 300 will have some form of SCD while 1 in 600 will have sickle cell anemia (Hgb S‐S). SCD is inherited in an autosomal recessive manner.