Red Blood Cell Disorders 2 Flashcards
What is the function of glutathione in the vascular system?
Neutralizes oxidants that may cause hemolysis
What is the result of reduced glutathione (GSH)?
RBC oxidative stress resulting in damage and hemolysis
What condition is a deficiency in the enzyme needed for the synthesis of glutathione?
Glucose-6-phosphate dehydrogenase deficiency (G6PD)
What is the enzyme responsible for GSH synthesis?
G6PD
What gender is most commonly affected by G6PD deficiency and why?
Males (X-linked condition)
What is the most common method of decreased glutathione production?
G6PD deficiency
Although asymptomatic usually, when does G6PD deficiency become symptomatic?
During exposure to an environmental stimulus that creates oxidative stress
What is the most common thing that causes symptoms of G6PD deficiency?
Infections
What general things can cause symptoms of G6PD deficiency?
1 infections
2 ADRs
3 Fava beans
What types of medications can cause ADRs and lead to symptoms of G6PD deficiency?
Aspirin, antimalarial meds (primaquine), nitrofurantoin (antibiotic for E. coli UTIs)
Heinz bodies and bite cells are microscopic findings associated with what hemopoietic condition?
Glucose-6-phosphate dehydrogenase deficiency
What race is more at risk for developing G6PD deficiency?
Africans (10% of African Americans)
What are the risks for G6PD deficiency?
Males, Africans, areas of endemic malaria
What condition involves complement-mediated hemolysis?
Paroxysmal nocturnal hemoglobinuria (PNH) or immunohemolytic anemias
What type of mutation is seen with PNH?
Acquired mutation of the PIGA gene in myeloid stem cells that is X-linked
What is the treatment for PNH?
Antibodies that inhibit the MAC
What is the characteristic sign of PNH?
Dark urine upon waking
In immunohemolytic anemias, what performs the hemolysis?
Splenic macrophages
How are immunohemolytic anemias diagnosed?
Coombs antiglobulin test
What class of antibodies are involved with attacking RBCs in warm antibody immunohemolytic anemia? Cold antibody?
Warm = IgG Cold = IgM
Which type of immunohemolytic anemia is usually primary in nature? Which can be secondary to infection?
Warm = primary Cold = primary or secondary to infection like EBV, mycoplasma, or B cell lymphomas
In 25% of cases, warm antibody immunohemolytic anemia can develop secondary to what conditions?
SLE, ADRs, B cell leukemia
What are the symptoms and signs of immunohemolytic anemias?
Chronic/mild anemia, jaundice, Raynaud phenomenon
What is the treatment for immunohemolytic anemias?
Usually none required
What kinds of things can cause traumatic hemolysis?
Prosthetic heart valves (“blender effect”) or narrowing vasculature
What kinds of things can cause narrowing of the vasculature resulting in traumatic hemolysis?
Aortic valve stenosis, DIC, SLE, invasive cancer
Microangiopathic hemolytic anemia is another name for what kind of hemolysis?
Traumatic hemolysis
What are RBCs called after damage due to traumatic hemolysis?
Schistocytes
What are other names for schistocytes based on their appearance?
“Burr cells” or “helmet cells”
Malaria is most common on which continents?
Africa and Asia
How many people die per year from malaria?
1 million
What is the pathogen responsible for malaria?
Plasmodium falciparum (protozoan)
What is the vector for malaria? What is the sole reservoir?
Vector = female Anopheles mosquito Reservoir = humans
What is the name for the hemolytic anemia associated with malaria?
Blackwater fever
Malaria becomes most lethal when it invades which body system?
CNS (seizures, convulsions, coma/death)
What is the treatment for malaria?
Chloroquine, primaquine, chemotherapy
Why is malaria becoming difficult to treat?
Drug-resistance
Deficiencies in which vitamins can lead to megaloblastic anemia?
Folic acid or vitamin B12
What is aplastic anemia?
Bone marrow failure
What is myelopththisic anemia?
Marrow infiltration
What is the effect of anemia of chronic disease?
Systemic inflammation
What four types of anemias are anemias of diminished erythropoiesis?
1 nutritional deficiencies
2 anemia of chronic disease
3 aplastic anemia
4 myelopththisic anemia
What is the prevalence of iron deficiency anemia in both developed and undeveloped countries?
DevelopING = 25-50% DevelopED = 10%
What is the overall most common cause of anemia?
Iron deficiency usually through nutritional deficiency
Where is 80% of iron stored?
Hemoglobin
Where do we find our iron stores?
Liver, spleen, marrow, skeletal muscle
What protein transports iron?
Transferrin (serum ferritin)
What is the appearance of RBCs with iron deficiency anemia?
Microcytic and hypochromic
What is usually the reason for iron deficiency in developed nations? In developing nations?
DevelopED = chronic blood loss (abnormalities, GI issues, gynecological issues) DevelopING = decreased dietary intake
What are the 4 general causes of iron deficiency?
1 decreased dietary intake
2 chronic blood loss
3 malabsorption
4 increased metabolic demands (pregnancy or infancy)
What kinds of malabsorptive conditions can lead to iron deficiency?
Caron’s disease, celiac disease, ulcerative colitis, etc.
What is the treatment for iron deficiency anemia?
Iron supplementation
How is iron deficiency anemia diagnosed?
Low serum ferritin levels and high EPO levels
What are the signs and symptoms of iron deficiency anemia?
Fatigue, pale skin, impaired cognition, decreased immunity, fingernail spooning, pica
What is pica?
Appetite for substances of non-nutritive value (example = dirt)
Spooning of the fingernails would be a sign of what condition?
Iron deficiency anemia
Chronic blood loss can be caused by what conditions of the GI tract?
Ulcers, colon cancer, hemorrhoids, celiac, ulcerative colitis
Chronic blood loss can be caused by what conditions of the female genital tract?
Menorrhagia, metrorrhagia, leiomyoma, leiomyosarcoma
Folate and vitamin B12 are required for what important function in the body?
DNA synthesis
What is the result of megaloblastic anemia?
Inadequate DNA replication, production of megaloblasts, pancytopenia
What is pancytopenia?
Decreased RBCs, WBCs, and platelets (anemia, leukopenia, and thrombocytopenia)
Which type of nutritive anemia is NOT associated with neuralgic dysfunction: folate or vitamin B12?
Folate
What happens to folic acid after cooking?
Denatures 10-15 minutes after cooking
How is folate deficiency anemia diagnosed?
Macrocytes in peripheral blood, decreased serum folate, normal vitamin B12
What is another name for vitamin B12 deficiency anemia?
Pernicious anemia
What are the functions of vitamin B12?
DNA synthesis
Maintenance of PNS and spinal cord
What population is basically the only group that would be at risk of vitamin B12 deficiency anemia via diet?
Strict vegans
What is the most common cause of pernicious anemia?
Chronic malabsorption
How does chronic malabsorption lead to pernicious anemia?
Gastric mucosal atrophy due to decreased intrinsic factor
Pernicious anemia stems from an autoimmune disorder that attacks which specific things?
Parietal cells and intrinsic factor
Pernicious anemia is most common among what population?
Elderly (over 70 years)
What neurologic effect can be seen with vitamin B12 deficiency anemia?
Possible demyelination of the PNS and spinal cord (CNS)
What symptoms can be indicative of neuropathy associated with pernicious anemia?
Numbness, tingling, burning, ataxia
How is vitamin B12 deficiency anemia diagnosed?
Decreased serum vitamin B12, normal folate levels
What is the treatment for pernicious anemia?
Vitamin B12 therapy (leads to rapid recovery)
Even with treatment, which symptoms of pernicious anemia are unlikely to be resolved?
Neurological symptoms
Vitamin B12 deficiency anemia is associated with an increased risk of what type of cancer?
Gastric carcinoma
Anemia of chronic disease is most common among what population?
Hospitalized
What effect does inflammation have on erythropoiesis?
Decreases it
What 3 general categories of illness can cause chronic/systemic inflammatory disorders leading to decreased erythropoiesis?
1 microbial infection (osteomyelitis, lung abscess)
2 immune disorders ( RA, Crohn disease)
3 neoplasia (lymphoma, lung or breast cancer)
What are the features of anemia of chronic disease?
1 decreased iron-binding capacity
2 increased iron storage in marrow
3 serum ferritin
What is important about the features of anemia of chronic disease?
Used to rule out iron deficiency anemia
What is aplastic anemia?
Suppression of myeloid stem cells (bone marrow failure)
What kinds of viral infections present as an increased risk for aplastic anemia?
EBV, CMV, VZV
In what way is aplastic anemia autoimmune?
Autoreactive T cells attack marrow
What is the prognosis for aplastic anemia?
Unpredictable (worse when the cause is idiopathic)
What is a visible sign of thrombocytopenia commonly seen with aplastic anemia?
Petechiae
What class anemia symptom is characteristically absent in aplastic anemia?
Splenomegaly
What is the treatment for aplastic anemia?
Immunosuppressive meds (80% response rate)
What is the appearance of RBCs with aplastic anemia?
Normocytic, normochromic (reticulocytopenia, as well)
Myelophthisic anemia most commonly metastasizes to what location?
Bone (also to breast, lung, and prostate)
Myelophthisic anemia is seen in which conditions?
Chronic granulomatous disease (TB, Bridges-Good syndrome)
Lipid-storage disease (Niemann-Pick, type C)
Dacrocytes are a finding with what type of anemia?
Myelophthisic anemia
What is the treatment for myelophthisic anemia?
Marrow transplant
What is the difference between relative and absolute polycythemia?
Relative - result of decreased plasma
Absolute - increase of actual total RBC mass
Dehydration from vomiting, diarrhea, burns, and diuretics would cause what type of polycythemia?
Relative (due to decreased overall plasma)
What things could cause absolute polycythemia?
1 proliferation of myeloid stem cells (polycythemia vera)
2 increased EPO (hypoxia, altitude, exogenous EPO)
What is polycythemia vera?
Blood cancer with NO increase in EPO
Which leads to increased EPO: hypoxia, anemia, or polycythemia vera?
Both hypoxia and anemia
Which leads to decreased EPO: hypoxia, anemia, or polycythemia vera?
PCV
What are the features of polycythemia?
Pruritis of the skin, DVT, PE, TIA/stroke
