SICKLVIEW TULIP (20 TEST)

Haemoglobin S (Hb S) differs from the normal Haemoglobin A(Hb A) by a single amino acid mutation at position 6 of the beta chain; wherein glutamic acid is replaced by valine. During low oxygen conditions, the red blood cell morphology may range from mild elongation to irreversible elongated tactoid. This elongated filamentous tactoid formation results in the typical ’sickle’ appearance of the red blood cell.Individuals with sickle cell anemia (homozygous S/S) may have early mortality with vascular occlusions of multiple organ systems, severe hemolytic anemia and hypoxia. Individuals with sickle cell trait (heterozygous A/S) are usually asymptomatic. However, under certain conditions of reduced oxygen tension such as hypoxia during anaesthesia, flight in poorly pressurized airplanes, severe pneumonia, they can experience a sickle cell crisis.