Sickle-cell anemia symptoms typically manifest after how many months of age?

Sickle-cell anemia symptoms typically manifest around 6 months of age due to the physiological changes that occur in an infant's hemoglobin composition. At birth, infants have predominantly fetal hemoglobin (HbF), which usually prevents sickling of red blood cells. As they grow, fetal hemoglobin levels gradually decrease and are replaced by adult hemoglobin (HbA), which is more prone to sickling under conditions of low oxygen, dehydration, or infection. By around 6 months, the shift in hemoglobin types leads to the expression of the sickle-cell disease phenotype, resulting in notable clinical symptoms. This timing aligns with the risk of vaso-occlusive crises, pain episodes, and other related complications emerging as the child's body starts to produce hemoglobin that can sickle. Understanding this transition is crucial in identifying and managing sickle-cell anemia in affected infants.