Flashcards in Anemia Due to Hemolysis Deck (19)
Hemolysis is defined as __________.
decreased RBC survival or an increase in RBC turnover beyond the normal range
RBCs can survive in blood for _________.
120 days (+/- 20 days)
Marrow production can increase by ______.
List five cellular processes associated with normal turnover.
- decreased enzyme activity
- changes in calcium balance
- oxidative injury
- changes in membrane surface constituents
- antibodies attaching to membrane surface
What lab values are typically elevated in hemolytic anemia?
- reticulocyte count
- serum/urine hemoglobin
- bilirubin (unconjugated)
- LDH, SGOT ("housekeeping enzymes")
What is the most common molecular abnormality in hereditary spherocytosis?
Hereditary spherocytosis presents with _______.
anemia, intermittent jaundice, splenomegaly, and responsiveness to splenectomy
Other than spectrin deficiency, spherocytosis can also be caused by _________.
ankyrin and band 3 defects
Familial spherocytosis is transmitted in a _________.
dominant (75%) and recessive (25%) manner
Conjugated hyperbilirubinemia results from ________.
Aplastic crisis is _________.
the temporary cessation of RBC production (which is markedly worse in patients with sickle cell)
Genetically, glucose-6-phosphate dehydrogenase deficiency is _______.
an X-linked recessive disorder
G6PD is involved in the ______ pathway, which produces NADPH that then leads to ________.
pentose; glutathione production--important for production against oxidative damage
In autoimmune hemolytic anemia, ______ causes intravascular hemolysis and _____ causes extravascular hemolysis.
Splenic hemolysis is referred to as _______.
In extravascular hemolysis, macrophages ________.
swallow RBCs in the spleen, storing iron in ferritin and releasing protophorphyrin as bilirubin
In the liver, bilirubin released by macrophages is _________.
metabolized in the phase II pathway (by addition of a glucuronic acid
Describe what happens in the absence of glutathione (as found in G6PD deficiency).
Inability to protect against oxidation results in denatured hemoglobin that binds to the membrane, damaging the cell.