Sickle Cell Anemia

Health Aspects of the Pre-Departure Phase of Migration

“…Some genetic conditions, such as the hemoglobinopathies more common in the Levant and other areas [35], have post-immigration implications in locations where these genetic features had not evolved and were not normally distributed [36]. The introduction of sickle cell disease into the Americas [37] or the differences in malignancy incidence reflected in some migrant populations embedded in host environments [38] are examples of these impacts. Another example is provided by studies on the international movement of Helicobacter pylori [39], which has post-infection, chronic consequences, including malignancy.…”

Pulmonary Complications of Sickle Cell Disease

“…and Thomas D. Verdegem, M.D. Sickle cell anemia and its variants are inherited disorders of hemoglobin (Hb) structure characterized by hemolytic anemia, frequent infections, and microvascular obstruction by rigid erythrocytes (RBC) producing acute and chronic ischemia and ultimately resulting in organ damage from infarction, necrosis, and fibrosis. 1 The clinical features of the disease are the direct result of the substitution of valine for glutamic acid at position 6 of the beta-globin subunit of the hemoglobin tetramer, which allows intracellular polymerization of Hb molecules following deoxygenation and mediates the morphologic transformation from the normally flexible, biconcave shape to the rigid sickle shape. Repetitive episodes of sickling cause RBC dehydration, cytoplasmic and membrane rigidity, and an increase in intracellular Hb concentration.…”

“…These alterations produce a heterogeneous population of RBC of increasing density, including very dense discocytes and irreversibly sickled cells (ISC). [1][2][3] These very dense discocytes and ISC are poorly deformable and are responsible for the elevated blood viscosity and microvascular occlusion of the disease. 2,4 Sickle cell anemia is the term applied to the homozygous form of the disease (Hb SS); it is the most common variant and generally has the most severe clinical manifestations.…”

Lung Disease in Sickle Cell Anemia: A Tropical Disease with a Twist

“…The pathogenesis of the sickling phenomena has been extensively reviewed. [10][11][12] A genetic substitution of valine for glutamic acid at the 6 position of the beta chain of hemoglobin is the cause for the abnormal physical properties of the hemoglobin S molecule which is manifested as sickle cell disease. The formation of sickled red blood cells is a result of intracellular polymerization of hemoglobin S.…”