Anemia

Question 1

What is anemia

Answer 1

A reduction in red blood cell count, hemoglobin content, or both.

Question 2

Define Erythropoiesis

Answer 2

The process of production of red blood cells (erythrocytes) in the body

Question 3

What hormone stimulates erythropoiesis ?

Answer 3

Erythropoietin ( a glycoprotein, release from the kidneys when renal O2 tension declines)

Question 4

Mention two disturbances of erythropoiesis

Answer 4

1.Cell multiplication is inhibited because DNA synthesis is insufficient. This occurs in deficiencies of vitamin B12 or folic acid (macrocytic hyperchromic anemia). 2. Hemoglobin synthesis is impaired. This situation arises in iron deficiency, since Fe2+ is a constituent of hemoglobin (microcytic hypochromic anemia).

Question 5

Deficiencies of vitamin B12 or folic acid

Answer 5

Macrocytic hyperchromic anemia

Question 6

iron deficiency, since Fe2+ is a constituent of hemoglobin

Answer 6

Microcytic hypochromic anemia

Question 7

General signs and symptoms of anemia

Answer 7

include fatigue, rapid heart- beat, shortness of breath, pale skin, dizziness, and insomnia.

Question 8

Anemia can be caused by

Answer 8

chronic blood loss, bone marrow abnormalities, increased hemolysis, infections, malignancy, endocrine deficiencie , renal failure, and a number of other disease states.

Question 9

Nutritional anemias are caused by dietary deficiencies of substances such as

Answer 9

iron, folic acid, and vitamin B12 (cyanocobalamin) that are necessary for nor- mal erythropoiesis.

Question 10

Vitamin B12 is also known as

Answer 10

Cyanocobalamin

Question 11

Individuals with anemia that has a genetic basis, such as sickle cell disease, can benefit from pharmacologic treatment with actions beyond nutritional supplementation, such as

Answer 11

hydroxyurea.

Question 12

Vitamin B12 (cyanocobalamin) is produced by

Answer 12

bacteria; B12 generated in the colon.

Question 13

Which food products are rich sources of the vitamin B12 ?

Answer 13

Liver, meat, fish, and milk

Question 14

Hydroxycobalamin is also known as

Answer 14

Vitamin B12a

Question 15

Deficiencies of vitamin B12 can result from

Answer 15

Either low dietary levels or, more commonly, poor absorption of the vitamin due to the failure of gastric parietal cells to produce intrinsic factor (as in pernicious anemia), or a loss of activity of the receptor needed for intestinal uptake of the vitamin.

Question 16

Intrinsic factor is

Answer 16

a glycoprotein produced by the parietal cells of the stomach, and it is required for vitamin B12 absorption.

Question 17

In addition to gen- eral signs and symptoms of anemia, vitamin B12 deficiency anemia may cause

Answer 17

tingling (pins and needles) in the hands and feet, diffi- culty walking, dementia and, in extreme cases, hallucinations, para- noia, or schizophrenia

Question 18

Folate deficiency may be caused by

Answer 18

1) increased demand (for example, pregnancy and lacta- tion), 2) poor absorption caused by pathology of the small intestine, 3) alcoholism, or 4) treatment with drugs that are dihydrofolate reduc- tase inhibitors (for example, methotrexate, pyrimethamine, and trim- ethoprim).

Question 19

A primary result of folic acid deficiency is

Answer 19

megaloblastic anemia (large-sized red blood cells), which is caused by diminished synthesis of purines and pyrimidines. This leads to an inability of erythropoietic tissue to make DNA and, thereby, proliferate

Question 20

To avoid neurological compli-cations of vitamin B12 deficiency , it is important to

Answer 20

evaluate the basis of the megaloblastic anemia prior to instituting therapy. Both vitamin B12 and folate deficiency can cause similar symptom .

Question 21

Folic acid is well absorbed in the

Answer 21

jejunum unless pathology is present. If excessive amounts of the vitamin are ingested, they are excreted in the urine and feces.

Question 22

Folic Acid food products source

Answer 22

Leafy vegetables and liver are rich in folic acid (FA)

Question 23

Causes of folic acid deficiency include:

Answer 23

insufficient intake, malabsorption in gastrointestinal diseases, increased requirements during preg- nancy. Antiepileptic drugs (phenytoin, primidone, phenobarbital) may de- crease FA absorption, presumably by in- hibiting the formation of monogluta- mine-FA. I

Question 24

Administration of FA can mask a

Answer 24

vitamin B12 deficiency.

Question 25

A frequent cause of iron deficiency is

Answer 25

chronic blood loss due to gastric/in- testinal ulcers or tumors.

Question 26

Iron deficiency results in

Answer 26

Iron deficiency results in impaired synthesis of hemoglobin and anemia

Question 27

The treatment of choice of iron deficiency (after the cause of bleeding has been found and eliminated) consists of the oral admin- istration of

Answer 27

Fe2+ compounds, e.g., fer- rous sulfate (daily dose 100 mg of iron equivalent to 300 mg of FeSO4, divided into multiple doses).

Question 28

Iron is stored in the

Answer 28

intestinal mucosal cells, liver, spleen, and bone marrow as ferritin (an iron–protein complex) until needed by the body. Iron is delivered to the marrow for hemoglobin production by a trans- port protein, namely transferrin.

Question 29

Iron deficiency results from

Answer 29

acute or chronic blood loss, from insufficient intake during periods of accel- erated growth in children, and in heavily menstruating or pregnant women. Thus, iron deficiency results from a negative iron balance due to depletion of iron stores and/or inadequate intake, culminating in hypochromic microcytic anemia (due to low iron and small-sized red blood cells).

Question 30

hypochromic microcytic anemia is

Answer 30

due to low iron and small-sized red blood cells

Question 31

In addition to general signs and symptoms of anemia, iron deficiency anemia may cause

Answer 31

pica (hunger for ice, dirt, paper, etc.), koilonychias (upward curvature of the finger and toe nails), and soreness and cracking at the corners of the mouth

Question 32

Oral preparations of iron include

Answer 32

fer- rous sulfate, ferrous fumarate, ferrous gluconate, polysaccharide iron complex, and carbonyl iron formulations. Of these preparations, ferrous sulfate is the most commonly used form of iron due to its high content of elemental iron and relatively low cost. The percentage of elemental iron varies in each oral iron preparation

Question 33

Parenteral formulations of iron, such as

Answer 33

iron dextran, sodium ferric gluconate complex, and iron sucrose,

Question 34

Adverse effects of iron

Answer 34

Adverse effects: Gastrointestinal (GI) disturbances caused by local irritation (abdominal pain, constipation, diarrhea, etc.) and dark stools are the most common adverse effects of oral iron sup- plements. Parenteral iron formulations may be used in those who cannot tolerate oral iron. Fatal hypersensitivity and anaphylactoid reactions can occur in patients receiving parenteral iron (mainly iron dextran formulations). A test dose should be administered prior to iron dextran. Excessive iron can cause toxicities that can be reversed using chelators such as deferoxamine.

Question 35

Human erythropoietin (epoetin alfa), produced by recombinant DNA technology, is effective in the treatment of ane- mia caused by

Answer 35

end-stage renal disease, anemia associated with human immunodeficiency virus infection, and anemia in bone mar- row disorders, anemias of prematurity, and anemias in some cancer patients.

Question 36

Antacids inhibit

Answer 36

iron absorption. Combination with ascorbic acid (Vitamin C), for protecting Fe2+ from oxidation to Fe3+, is theoretically sound, but practically is not needed.

Question 37

getting too little folate, also known as vitamin B-9, during pregnancy can cause?

Answer 37

spina bifida