|what are the common causes of chronic blood loss?||
In the United States: menorrhagia, gastrointestinal bleeding.
Worldwide: hook worm disease (necator americanus)
|What groups are at risk for dietary deficiency of iron?||
Premature infants: human milk is low in iron, and newborn iron is depleted within six months. Pregnant women may also require iron supplements.
The elderly are also at risk of dietary deficiency.
|List the common symptoms of anemia as well as the symptoms of severe anemia.||
Common: pallor, fatigue, dyspnea on exertion.
Severe: angina pectoris, glossitis, gastritis, koilonychia, and Plummer-Vinson syndrome.
|What are the iron study patterns in iron deficiency anemia?||
Serum iron is low.
TIBC is elevated.
Serum ferritin is low.
|How do you distinguish iron deficiency anemia from beta thalassemia minor?||
In beta thalassemia minor, the alpha-2 hemoglobin is increased.
|What are the three peripheral blood findings in macrocytic anemias? What is seen in the bone marrow?||
pancytopenia, global macrocytosis, hypersegmented neutrophils.
the bone marrow shows megaloblastic hyperplasia.
|Name eight causes of vitamin B12 deficiency megaloblastic anemia.||
pernicious anemia, total gastric resection, disorders of the distal Ilium, a strict vegetarian diet, intestinal malabsorption syndromes, blind loop syndrome, broad-spectrum antibiotic therapy, Diphyllobothrium latum infestation (fish tapeworm)
|How do you distinguish folate deficiency from vitamin B12 deficiency?||
There are no neurologic abnormalities in folate deficiency.
|Name six causes of folate deficiency anemia.||
dietary deprivation in alcoholics or dieters.
phenytoin or oral contraceptive therapy
folate acid antagonist chemotherapy
relative deficiency in hemolytic anemia
intestinal malfunction due to sprue or Giardia
|what are the iron study patterns in the anemia of chronic disease?||
Serum iron is low
TIBC is low.
Serum ferritin is elevated.
|what are some causes of aplastic anemia?||
dysfunction of cytotoxic T cells
chemicals such as benzene
therapeutic drugs such as chloramphenicol, sulfonamides, gold salts, chlorpromazine, antimalarial drugs, and alkylating agents.
Viral infection by parvovirus or hepatitis C.
|What is polychromatophilia?||
increased numbers of larger red cells that stain with a bluish cast. These are premature RBCs and would likely stain as reticulocytes.
|Which antibodies mediate warm antibody autoimmune hemolytic anemia versus cold agglutinin disease?||
|cold agglutinin disease is a complication of what diseases?||
infectious mononucleosis and mycoplasma pneumonia.
it may be a chronic complication of lymphoid neoplasms.
|What preventative measure can be taken to prevent erythroblastosis fetalis?||
administer anti-D IgG antiserum to D negative mothers at the time of delivery of a D positive child. this causes fetal red cells to be removed from maternal circulation.
|What are the possible causes of erythroblastosis fetalis?||
Maternal alloimmunization to fetal Rh antigens.
|What is the pathophysiology of paroxysmal nocturnal hemoglobinuria?||
Defect in the PIG-A gene causes impaired synthesis of the GPI anchor, which fixes CD55, CD59, and CD8 proteins to the cell surface. These proteins protect red cells from compliment mediated lysis.
|What are the possible molecular defects in hereditary spherocytosis? What is its inheritance?||
Spectrin, ankyrin, protein 4.1 or other RBC skeletal proteins.
|What is the pathophysiology of G6PD deficency? What is its inheritance?||
Lack of G6PD reduces the body's ability to deal with oxidative stress. G6PD is an X-linked disorder.
|What are sources of oxidative stress that can cause an episode of hemolysis in G6PD?||
drugs such as primaquine (anti malarial), sulfonamides, other oxidant drugs.
|How can you differentiate the presentation of pyruvate kinase deficiency from G6PD deficiency?||
In contrast to G6PD deficiency anemia, pyruvate kinase deficiency anemia is chronic and sustained.
|What is the inheritance of pyruvate kinase deficiency anemia?||
|What percentage of African-Americans carry the hemoglobin S gene? What advantages does the gene confer?||
The hemoglobin S gene confers resistance to malarial infection (Plasmodium falciparum).
|Specifically, what is the genetic defect in hemoglobin S disorders?||
A point mutation on chromosome 11 in codon six of the beta globin gene results in a substitution of valine for glutamic acid.
|What are the six symptoms of sickle cell anemia?||
severe hemolytic anemia
chronic leg ulcers
aplastic crises (parvovirus)
infectious complications (salmonella osteomyelitis)
|What are six clinical and laboratory signs of beta thalassemia?||
distortion of skull facial bones and long bones
microcytosis, hypochromia, target cells
increased Hemoglobin F
|What is sickle-cell thalassemia?||
Co-inheritance of hemoglobin S and thalassemia of the beta globin gene. Clinically similar to sickle cell anemia but less severe.
|What are possible causes of mechanical disruption leading to hemolysis? What is seen on the peripheral smear?||
aortic valve prosthetics
disseminated intravascular coagulation
thrombotic thrombocytopenic purpura
smear shows schistocytes or helmet cells
|What is the spectrum of clinical abnormalities in alpha thalassemia according to the number of deletions?||
one deletion: no abnormalities
two to three deletions: mild to moderate thalassemic symptoms
four deletions: hydrops fetalis
|What is hepcidin?||
A peptide hormone that decreases both intestinal iron absorption and the release of iron from macrophages. In anemia of chronic disease, proinflammatory cytokines induce hepatic synthesis of hepcidin. This causes serum iron to be low despite normal or even elevated iron stores (ferritin).