Pathoma: Normocytic Anemia with Extravascular Hemolysis Flashcards
Disorders with extravascular hemolysis often have some ________, too.
intravascular hemolysis
Hereditary spherocytosis results from ___________.
a hereditary defect in spectrin, ankyrin, or band 3.1
Histologically, hereditary spherocytosis leads to __________.
blebs of membrane breaking off, loss of central pallor, and anisocytosis
The MCHC (mean corpuscular hemoglobin concentration) will be _______ in hereditary spherocytosis, uniquely.
increased, because the loss of membrane leads to decreased cell volume and resultant increase in hemoglobin concentration
Features of the past medical history common to hereditary spherocytosis include ___________.
splenomegaly, bilirubin gallstones, and aplastic anemia second to parvovirus B19
Hereditary spherocytosis can be tested by placing RBCs in ___________.
a hypotonic sucrose solution (“osmotic fragility test”)
Anemia in hereditary spherocytosis will resolve in response to _________.
splenectomy
Following splenectomy (or other splenic dysfunction), _________ will appear on blood smears.
Howell-Jolly bodies (pieces of DNA in RBCs that would normally be removed by the spleen)
HgbS precipitates in response to _________.
deoxygenation, acidosis, and dehydration (precipitation is reversible)
_____ increases the levels of HgbF.
Hydroxyurea
Sickle cell results in _________ hemolysis.
extravascular, due to weakening of the red cell membrane
Because sickle cell disease results in extravascular hemolysis, there will also be _________ in those with sickle cell, similar to hereditary spherocytosis.
bilirubin gallstones, jaundice, and splenomegaly
__________ hemolysis results in low haptoglobin.
Intravascular
__________ leads to target cells.
Dehydration
Extramedullary hematopoiesis first occupies the _______, then the ________.
bone marrow; liver
Other than splenomegaly, those with sickle cell present with _________ (radiographical sign) and __________ (another type of organomegaly).
crew-cut appearance (extramedullary hematopoiesis of the skull bones); hepatomegaly
A common presenting sing of sickle cell disease in infants is ___________.
dactylitis (classically shown on exams with the hand of an African-American child)
Those with sickle cell can lose this organ (due to pathology, not medical).
Spleen
Without the spleen, patients are more susceptible to _______ organisms.
encapsulated (particularly Salmonella paratyphi osteomyelitis)
In sickle cell, the most common cause of death in children is ________, while in adults it is __________.
infection with encapsulated organisms; acute chest syndrome
Generall, those with sickle cell trait have less than _______ HbS.
50%
Those with sickle trait are usually asymptomatic, except for __________.
in the renal medulla, in which the hypertonicity induces sickling and patients can sometimes develop a decreased ability to concentrate urine
__________ can induce cells with any degree of HbS to sickle.
Metabisulfite (positive in those with the disease and the trait)
Hemoglobin C has _________ instead of valine.
lysine (lie-CCCCCEEEne)