Ch 14: RBC and Bleeding Disorders Flashcards
what is hereditary spherocytosis
type of hemolytic anemia
mutations lead to an insufficiency of a RBCs membrane skeletal components
rounded cells get stuck in spleen and their destruction causes splenomegaly
what is thalassemia
mutations that decrease the synthesis of a or b-globin chains in a hemoglobin molecule
how does thalassemia affect the liver and speen
causes hepatosplenomegaly (up to 1500 g)
how does thalassemia affect bone marrow
hematopoiesis causes erosion of exsisting cortical bone and therefore new bone formation
crewcut appearence on radiographs
what pathology can thalassemia treatments cause
both excessive amounts of erythropoietin and blood transfusions can cause hemocromatosis
what is hemochromatosis
secondary iron overload seen in beta-thalassemia cases
what hydrops
accumulation of edemic fluid in the fetus during intrauterine growth
can be caused by thalassemias
what is immune hydrops
hemolytic disease caused by blood group antigen incompatibility between mother and fetus
what is non-iummune hydrops
edemic fluid build up due to heart defects, chromosome abnormalities, or fetal anemia
what is hydrops fetalis
-what does the fetus present with
most severe form of a-thalassemia that is caused by deletion of all four a-globin genes
fetus presents with edema, cystic hygroma, and kernicterus
what is a cystic hygroma
fluid accumulation in the soft tissues of the neck in a fetal hydrops case
what is kernicterus
most serous threat of fetal hydrops
CNS damage - bilirubin accumulation in the basal ganglia deep to the ventricles
what is sickle cell disease
point mutation in b-globin that causes polymerization of deoxygenated hemoglobin
leads to sickle shaped RBC
what is autosplenectomy
a consequence of sickle cell anemia
sickled cells get trapped in splenic sinusoids, causing the spleen to shrink
what are gandy-gamna nodules (bodies)
consequence of sickle cell anemia
“tobacco flecks”
yellow-brown spots in the splenic parenchyma that are made of iron and salt deposits
caused by chronic episodes of vasco-occlusion in the white pulp of the spleen
how can sickle cell anemia affect the gallbladder
excess breakdown of hemoglobin can cause hyperbilirubinemia and formation of gallstones