Lecture 8b :RBCDisorders

Fill-in-the-blank flashcards covering anemia types, causes, and polycythemia based on the provided lecture notes.

Anemia is an abnormally low number of circulating or Hb level or both.

RBCs (red blood cells)

Low oxygen-carrying capacity → tissue .

hypoxia

Common symptoms include fatigue, weakness, dyspnea, and .

angina

Hypoxia of brain tissue → , faintness, and dim vision.

headaches

Tachycardia &/or palpitations = compensating for O₂ with increased cardiac .

output

Anemia is often not a disease but an indication of a disease process/body .

dysfunction

Typical causes: Excessive blood loss – acute or chronic; Hemolysis; Deficient erythropoiesis.

excessive

Often bc of nutritional deficit OR bone marrow .

failure

Iron Deficiency Anemia is caused by deficiency.

iron

Iron is recycled after RBCs are broken down; some is lost in the feces and must be replaced via the .

diet

Average diet gives ~ mg of iron.

20

Loss of iron through bleeding is the cause in the U.S.

most common

Worldwide main cause is parasitic infection (various parasitic worms).

parasitic

During growth periods there is a greater for iron.

demand

Causes: Decreased Hb synthesis → decreased O₂ delivery to cells → , headaches, tachycardia.

fatigue

Vitamin B12 is needed for synthesis.

DNA

Vitamin B12 is found in all animal-based foods; deficiency by diet is rare except in vegetarians.

strict

Normal function = Gastric parietal cells secrete intrinsic factor → factor binds to Vitamin B12 → protection from digestive enzymes → Vitamin B12-Intrinsic Factor complex travel to .

ileum

Any error in the process = B12 deficiency.

deficiency

Impair DNA synthesis & RBC/nuclear development → abnormal RBCs (very large) → RBC death.

macrocytic (very large)

Megaloblastic anemia can cause neurological issues due to deficiency.

B12

Megaloblastic Anemia (Folic Acid Deficiency) is caused by (Vitamin B9) deficiency.

Folic acid

Folic acid works closely with Vitamin B12 and is needed for DNA synthesis & RBC maturation.

folate/Folic acid

Folic acid is found in vegetables, fruits, and meats; also in cereals (folic acid fortified); cooking destroys most of it.

folic acid

Typically a issue.

dietary

Causes can be absorption issues (e.g., celiac disease) or .

pharmaceuticals

Recall that folic acid deficiency is connected to birth defects (neural tube defects).

neural tube defects

Other Common Complications: Same as B12 deficiency anemia EXCEPT NO symptoms.

neurologic

Aplastic anemia is caused by a failure of the marrow to produce enough red blood cells.

bone marrow

Potential triggers for aplastic anemia include autoimmune disorders, exposure to , certain medications, and viral infections.

toxins/radiation

Sometimes .

idiopathic

Symptoms: Fatigue/weakness, Shortness of breath, unexplained or easy bruising, pallor.

fatigue/weakness

In chronic diseases, T cells trigger cytokines → erythropoietin → decreased RBC production.

suppress

Acquired hemolytic anemia is caused by agents to the red blood cell.

extrinsic

Common drugs include cephalosporins, penicillins, and .

levofloxacin

Infections such as can cause acquired hemolytic anemia.

malaria

Polycythemia is defined by a hematocrit > % in men and > % in women.

54%; 47%

Types: Relative or Absolute.

Absolute

Relative polycythemia results from a loss of plasma volume; causes: .

dehydration

Absolute primary polycythemia is a proliferative disease of the bone .

marrow

Absolute primary polycythemia treatment: periodic .

phlebotomy

Absolute secondary polycythemia is due to increased levels of in response to hypoxia.

erythropoietin

Treatment – counteract the .

hypoxia