Normocytic Anemia Flashcards
What normocytic anemia progresses to a microcytic anemia?
ACD
If a patient with normocytic anemia has pancytopenia on CBC, what should you expect?
Aplastic Anemia
What are the major causes of aplastic anemia?
Idiopathic
Chemicals
Infection (parvovirus)
Radiation
What do you see when you look at bone marrow in an aplastic anemia patient?
nothing–hypocellular and lots of fat
How do you treat aplastic anemia?
- Remove cause (ex. drug)
- Transfusions
- Marrow-stimulating drugs (ex. epoetin alpha, darbepoetin, filgrastim, sargramostim)
How does chronic renal failure lead to anemia?
Renal tubular cells produce EPO (under hypoxic conditions), but with kidney failure, you have a decrease in EPO synthesis so decreased hematopoiesis
What do you see on a peripheral smear of a patient with chronic renal failure?
acanthrocytes (burr cells)
How do you treat non-hemolytic anemia due to renal failure?
Epoetin alpha
Darbepoetin
(agonists of EPO receptors)
What condition must you NEVER give a patient epoetin alpha and darbepoetin?
if they have hemoglobin over 12 g/cL
What are the adverse effects of erythropoietin-stimulating drugs?
hypotension and thrombosis
Is hereditary spherocytosis due to an intrinsic or extrinsic problem?
intrinsic defect in membrane band3, spectrin, or ankyrin leading to TOO LITTLE MEMBRANE
What does a peripheral smear of someone with hereditary spherocytosis show? Why? How does this relate to their presentation?
1) spherocytes (too little membrane)
2) Howell-Jolly bodies (must remove spleen in some cases, because you have splenomegaly due to premature removal of RBCs from spleen)
How do you diagnose hereditary spherocytosis?
positive osmotic fragility test
How can you treat hereditary spherocytosis?
splenectomy
Why is G6PD important for RBCs?
you cannot make NADPH, and without NADPH, you cannot prevent oxidative stress:
- Hgb --> methemoglobin (keep iron in Fe2+) - Regenerate GSH from GS-SG
What are the two major causes of G6PD deficiency?
X-linked genetic disorder
Eating Fava Beans
What do you see on a peripheral smear of G6PD deficiency? Why?
1) Bite cells (spleen phagocytes removes chunks of oxidized hemoglobin from the cell)
2) Heinz bodies (precipitates of oxidized hemoglobin)
3) Blister cells (oxidative damage leads to unstable hemoglobin)
Patients with G6PD deficiency should avoid what?
Certain drugs (ex. dapsone and primaquine which are anti-malarial and sulfa drugs)
How do you diagnose G6PD deficiency?
Do an enzyme activity test (but wait to do it!)
Why is pyruvate kinase important for cells?
Helps produce ATP for:
- RBC membrane maintenance
- RBC Na/K ATPase (prevention of lysis)
What causes pyruvate kinase deficiency?
Autosomal Recessive genetic disorder
What does a peripheral smear look like for someone with pyruvate kinase deficiency? Why?
1) Polychromasia (bluish residual RNA with ramped up RBC synthesis)
2) nRBCs
3) Increased reticulocytes
How do you diagnose PK deficiency?
enzyme activity test
What causes paroxysmal nocturnal hemoglobinuria?
Mutation in PIG-A gene on X chromosome that codes a glycolipid that anchors proteins (like DAF and CD59) which remove complement (that is ramped up during sleep when we get respiratory acidosis).
What is the presentation of PNH?
intermittent hemolysis in adults
assoicated with thrombosis
What does a peripheral smear look like with someone who has PNH?
normal
How do you diagnose PNH?
urine hemosiderin flow cytometry (CD55-, CD59-)
How do you treat PNH?
Bone marrow transplant
Ecluzimab
What causes sickle cell disease (HbS)?
AR mutation leading to Base change in AA#6 Glu (negative)–> Val (neutral) of beta chain of Hgb
What causes HbC?
Base change in AA#6 Glu (negative)–> Lys (positive)
How does HbS lead to symptoms?
HbS polymerizes (due to valine cross-links) when deoxygenated forming needle-like structures that are vasooclusive and that lead to hemolysis of RBCs
What triggers HbS sickling?
hypoxia anemia cold Acidosis dehydration
How do people present with HbS?
Newborns asymptomatic (because HbF is protective)
Dactylitis (children, vaso-occlusive infarcts in bone)
Pain
Leg ulcers
Asplenia
Why do you get asplenia with sickle cell disease? What is the effect of this?
spleen atrophies from vascular occlusion
You are at increased risk of infection and death from encapsulated bacteria (ex. S. pneumoniae, H. influenzae, and Salmonella paratyphi)
How do you diagnose sickle cell?
HPLC
Hgb electrophoresis
Sickle cells in peripheral smear
How do you treat sickle cell disease?
hydration avoidance of triggers pain management hydroxea urea (hypomethylates DNA to "turn on" fetal Hgb) Bone marrow transplant
In what case would you see jaundice with an intravascular hemolysis?
if Hgb saturates haptoglobin you can get jaundice (this is NOT common)
What causes a microantiopathic hemolytic anemia?
prosthetic heart valves
dysfunctional/calcified aortic valve
What causes a microangiopathic hemolytic anemia?
DIC
TTP
SLE
What cells do you expect to see in a peripheral smear of a microangiopathic hemolytic anemia?
schistocytes (helmet cells)- because cells are being crushed/sliced
What leads to TTP?
antibodies made against AdamTS13 so that it cannot properly trip VWF. Leads to small clots formed in peripheral vessels that can slice RBCs as they zoom by
A patient with TTP presents with what?
FAT RN: (young adults, mostly females) Fever Anemia Thrombocytopenia (thrombosis, hemorrhaging, bruising) Renal failure Neurological defects
How do you treat TTP?
plasmapheresis
What is the cause of a warm autoimmune hemolytic anemia?
IgG targeted at RBC leading to extravascular hemolysis (RES in spleen) or intravascular hemolysis (due to complement-mediated lysis)
What does a peripheral smear of a patient with warm autoimmune hemolytic anemia show?
microspherocytes (partial phagocytosis from RES)
How do you diagnose a warm autoimmune hemolytic anemia?
DAT (positive for Ab AND complement)
Direct Ab
Warm autoimmune hemolytic anemia is usually associated with what?
malignancies (poor prognosis)
How do you treat warm autoimmune hemolytic anemia?
Steroids Splenectomy Rituximab Azathrioprine Blood transfusion
What is the cause of cold autoimmune hemolytic anemia?
IgM targed RBC–> complement MAC leading to intravascular hemolysis (jaundice not as common) and hemoglobinuria
What does a peripheral blood smear look like in a patient with cold autoimmune hemolytic anemia?
aggregates of RBCs
How do you diagnose cold autoimmune hemolytic anemia?
Direct Ab test
DAT positive for complement
Cold autoimmune hemolytic anemia is usually associated with what?
viral syndromes and infectious diseases (chronic/seasonal)
How do you treat cold autoimmune hemolytic anemia?
steroids
What is the most common and deadly protozoal infections in humans?
malaria
plasmodium falciparum is most lethal
What are the presenting symptoms of malaria?
high fevers, dark urine, jaundice after travel to subtropics
What is the vector for malaria?
mosquito vector
How do you diagnose malaria?
- Peripheral blood smear (very thick)
- Identify merozites and gametocytes
What protozal infection can you get from ticks in NE USA?
babesia
What does a peripheral blood smear look like in a patient with babesia?
Strange looking with large things that look like they come from a karyotype
What parastie infection can you get from sand flies in Peru, Ecuador and Columbia?
Bartonella
What are the presenting symptoms of Bartonella?
Acute: anemia
Chronic: Peruvian warts
Splenomegaly
What does a peripheral blood smear look like in a patient with Bartonella?
basophlic intracellular parasite (looks like bits of string)
What is the prognosis of Bartonella?
FATAL if not treated with antibiotics
How does anemia occur after a C. Perfringens infection?
It is a normal skin flora that releases alpha toxin that cuases hemolysis and gas gangrene
When would you expect anemia due to C. perfringens?
after trauma, septic abortion, cholecystitis
What does a peripheral blood smear look like in a patient with C. perfringens?
accumulation of microspherocytes HgB shadow (very faint cells)
