![]() ![]() Limited studies conducted thus far have indicated adaptive immune abnormalities in individuals with SCA 21– 29. The current recommendations for usage of vaccines in children with SCA are based on efficacy trials done mostly in individuals without SCA 12, 18– 20. Thus, besides vaccines against bacterial infections, introduction of a malaria vaccine could have enormous impact on mortality in children with SCA in sub-Saharan Africa 17. Besides bacterial infections, children with SCA in sub-Saharan Africa are also at risk of mortality from malaria which is endemic in the region 14– 16. In sub-Saharan Africa, where the burden of SCA is highest, pneumococcal vaccines are currently being introduced. To this effect, pneumococcal vaccines have been the standard of care for individuals with SCA in developed countries since their introduction 8, 12, 13. However, for more sustainable control of infections, engagement of the immune system via vaccination is believed to be the most durable and cost effective approach 10, 11. The use of penicillin prophylaxis has reduced the mortality attributable to invasive pneumococcal disease in children with SCA 7– 9. Pneumococcal pneumonia, septicemia and meningitis in particular are important causes of morbidity and mortality in individuals with SCA, especially at younger age 3, 5, 6. Particularly, the risk is high for infection with encapsulated bacteria such as Streptococcus pneumoniae and Haemophilus influenzae 2– 4. Individuals with Sickle Cell Anemia (SCA), the homozygous (HbSS) sickle cell disease (SCD), are at an increased risk of invasive bacterial infections 1– 3. This article summarizes our current understanding of lymphocyte biology in SCA, and highlights areas that warrant future research. Studies should be encouraged of different SCA populations, including sub-Saharan Africa where the burden of SCA is highest. Thus, in order to optimize the use of vaccines in SCA, a thorough understanding of T and B lymphocyte functions and vaccine reactivity among individuals with SCA is needed. These changes occur on the background of immune activation characterized by predominance of memory CD4+ T cell phenotypes, increased Th17 signaling and elevated levels of C-reactive protein and pro-inflammatory cytokines IL-6 and TNF-α, which may affect the immunogenicity and protective efficacy of vaccines available to prevent infections in SCA. This includes reduction in the proportion of circulating CD4+ and CD8+ T cells, reduction of CD4+ helper : CD8+ suppressor T cell ratio, aberrant activation and dysfunction of regulatory T cells (T reg), skewing of CD4+ T cells towards Th2 response and loss of IgM-secreting CD27+IgM highIgD low memory B cells. Besides the described dysfunction in innate immunity, including impaired opsonization and phagocytosis of bacteria, evidence of dysfunction of T and B lymphocytes in SCA has also been reported. Together with our multidisciplinary clinic partners, we can help coordinate care with your primary obstetrician to provide the highest level of care for you and your baby.Individuals with sickle cell anemia (SCA) have increased susceptibility to infections, secondary to impairment of immune function. Our Specialty Care TeamĪll of our Maternal-Fetal Medicine specialists are experts in taking care of patients with complicated medical conditions before and during pregnancy. Our team of experts collaborate with other specialists to carefully evaluate and treat the needs of you and your baby. Whenever possible, we encourage patients with blood conditions to begin planning with your medical team before conception to put the steps in place to ensure a healthy pregnancy. Fetal and Neonatal alloimmune thrombocytopenia (NAIT).Bone marrow disorders including aplastic anemia.Hemoglobinopathies like sickle cell disease or thalassemias.Other factor deficiencies and platelet disorders.Idiopathic thrombocytopenic purpura (ITP).Pre-existing blood conditions may include: ![]() Iron and folate needs also change during pregnancy, which can complicate anemia and other blood disorders. ![]() Pregnancy increases the risk of clotting and delivery can increase risks of hemorrhage in patients with coagulation disorders. Our multidisciplinary team of maternal-fetal medicine specialists, hematologists, anesthesiologists, nurses and social workers provide preconception consultations, as well as advanced prenatal, delivery and postpartum care. Patients with hematologic (blood) conditions, including inherited and acquired blood disorders, can face unique challenges during pregnancy and delivery.
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