blood disorders 2/3

Question 1

what is the haemoglobin molecude made up of?

Answer 1

Two pairs of polypetide chains (the globins)•Four complexes of iron plus protoporhyrins(the hemes)
oxygen carrying protein of erythrocytes

Question 2

where is iron in the body bound to?

Answer 2

Total body iron is bound to heme or stored bound to ferritin or hemosiderin mononuclear phagocytes and hepatic parenchymal cells

Question 3

how much iron is lost every day? and where from?

Answer 3

Less than 1 mg per day is lost in the urine, sweat, epithelial cells, or from the gut

Question 4

what is transferrin? and where is it syntheised?

Answer 4

Transferrin: a glycoprotein
•primarily synthesized in the liver
also synthesized by tissue macrophages, submaxillary and mammary glands, ovaries and testes

Question 5

what is an Apotransferrin?

Answer 5

Transferrin without attached iron

Question 6

is heme/ ferrous iron better absorbed than non-heme/ferrous iron?

Answer 6

heme/ ferrous iron is better absorbed

Question 7

what does Gastric acidity help?

Answer 7

helps to keep iron in the ferrous state and soluble in the upper gut

Question 8

does Formation of insoluble complexes with phytate or phosphate increase/ decrease iron absorption?

Answer 8

decrease

Question 9

how is iron absorption increased?

Answer 9

Iron absorption is increased with low iron stores and increased erythropoietic activity, e.g. bleeding, haemolysis, high altitude

Question 10

how does high vs low iron plasma affect loss by shedding?

Answer 10

low- decreases loss by shedding

high- increases loss by shedding

Question 11

what sort of anemia is iron deficiency anemia?

Answer 11

Hypochromic microcytic anaemia

Question 12

what causes Hypochromic microcytic anaemia?

Answer 12

Inadequate iron intake in diet, as in infants during periods of rapid growth or with adolescents subsisting on an inadequate diet
–Inadequate reutilization of iron present in red cells due to chronic blood loss

Question 13

whats the main lab test you would use to classify iron deficiency anaemia?

Answer 13

Low serum ferritin and serum iron

•Much higher than normal serum iron-binding protein with a much lower than normal percent iron saturation

Question 14

how do you trest iron deficiency anaemia?

Answer 14

treat the cause rather than the symptoms

supplementary iron

Question 15

what are examples of iron deficiency anaemia?

Answer 15

infant with a history of poor diet
• In adults: a common cause is chronic bloodloss from the gastrointestinal tract, as maybe caused by a bleeding ulcer or anulcerated carcinoma of the colon
• In women: excessive menstrual blood loss
• Too frequent blood donations

Question 16

what are foods/ drugs that impair iron absorption?

Answer 16

• Milk
• Tea
• Phytates
• Antacids
• Tetracyclines
• Fluoroquinolones

Question 17

what are foods/ drugs that aid iron absorption?

Answer 17

• Vitamin C
• Meat
• Orange juice

Question 18

what are the 3 different types of iron salts you can give?

Answer 18

Ferrous sulfate
Ferrous gluconate
Ferrous Fumarate

Question 19

when is parental iron necessary?

Answer 19

Necessary in individual unable to absorb oral iron due to
–Malabsorption syndromes
–Due to surgical procedure
–Inflammatory condition involving GIT
•Patients who can not tolerate oral preparations
•Patients with chronic renal failure receiving treatment with erythropoietin

Question 20

what are the 2 types of parental iron?

Answer 20

–Iron – dextran(deep intramuscular injection or slow intravenous infusion)
–Iron - sucrose(slow intravenous infusion)

Question 21

what are the unwanted affects of iron?

Answer 21

Oral iron administration are dose-related and include nausea, abdominal cramps and diarrhoea
.•Parenteral iron can cause anaphylactoid reactions
•Acute iron toxicity, usually seen in young children who have swallowed attractively coloured iron tablets in mistake for sweets,occurs after ingestion of large quantities of iron salts.
•Chronic iron toxicity or iron overload is virtually always caused by conditions other than ingestion of iron salts

Question 22

where are vitb12 and folic acid found?

Answer 22

vit b12- found in meats/ livers/ animal proteins

folic acid- found in green veg

Question 23

what are folic acid and vit b12 needed for?

Answer 23

Both are required not only for normal hematopoiesis but also for normal maturation of many other types of cells

Question 24

what is the maturation of red blood cells know as?

Answer 24

megaloblastic erythropoiesis

Question 25

what are the 3 risk factors for folate deficiency?

Answer 25

``` Decreased absorption caused by •Coeliac disease •Crohn’s disease Inadequate intake caused by •Alcoholism •Advanced age •Malnutrition/poverty Hyperutilization caused by •Pregnancy •Growth spurts ```

Question 26

what is folic acid made up from?

Answer 26

pteridine +para-aminobenzoic acid+ glutamic acid)

Question 27

where does the absorption of folic acid occur?

Answer 27

in the upper small intestine

Question 28

how do anemia and folic acid deficiency symptoms differ

Answer 28

In folate deficiency anaemia similar symptoms to pernicious anaemia except neurologic manifestations are generally not seen

Question 29

what is Pernicious anaemia?

Answer 29

Vitamin B12 deficiency macrocytic anaemia | Often associated with autoantibodies directed against gastric mucosal cells and intrinsic factor

Question 30

what are the causes of vitb12 deficiency?

Answer 30

Following gastric resection to treat ulcer disease or to treat gastric cancer •Following gastric bypass procedures to treat obesity •Due to distal small bowel resection or disease(because Vitamin B12is absorbed in the ileum) •Nutritional deficiency in strict vegetarians after many years without meat, eggs and dairy products

Question 31

what is the treatment of vit b12 deficiency?

Answer 31

intramuscular administration of Vitamin B12available as cyanocobalamin(C) or hydroxocobalamin h-1000μg i.m.in five doses 2or3days apart followed by maintenance therapy 1000μgevery three months

Question 32

what is retained in the body longer H/C?

Answer 32

h

Question 33

what is the treatment of folate deficiency?

Answer 33

Oral folic acid 5mg daily for 3 weeks (acute deficiency) | •Maintenance therapy 5mg once weekly

Question 34

what are Pregnant women given and before conception?

Answer 34

folic acid

Question 35

what causes depression of bone marrow?

Answer 35

anaemia- mild supression marrow injured by radiation, anticancer drugsor toxic chemicals; aplastic anaemia, which ismuch more serious, can cause severe bone marrow damage A manifestation of an autoimmune disease in which the body’s own cytotoxic T lymphocytes attack and destroy the marrow stem cells

Question 36

what does treatment of Bone Marrow Suppression, Damage, or Infiltration depend on?

Answer 36

on cause: –Blood and platelet transfusions–Immunosuppressive drugs–Bone marrow transplant in highly selected cases of aplastic anaemia

Question 37

what are the 4 types of genetically determined abnormalities of red blood cells?

Answer 37

Abnormally shaped cells Abnormal hemoglobins:–Hemoglobin S (sickle hemoglobin)–Hemoglobin C–both predominantly - persons of African descent Defective hemoglobin synthesis:–in thalassemia, the globulin chains are normal but their synthesis defective- normally greek/italian Red cell enzyme deficiencies:–very common one is deficiency of an enzymecalledglucose-6-phosphatasedehydrogenase, where the enzyme is unstable and does not function normally

Question 38

what is Acquired Hemolytic Anaemia?

Answer 38

The red cells are normally formed but are unable to survive normally because they are released into a “hostile environment” •Red cells unable to survive when antibodies attack and destroy •Red cells destroyed by mechanical trauma

Question 39

what is Polycythemia?primary

Answer 39

manifestation of a diffuse hyperplasia of bone marrow of unknown etiology –Characterized by overproduction of red cells, white cells, and platelets

Question 40

what is secondary polycythemia?

Answer 40

Compensatory increase in red blood cells(increased erythropoietin production) as a response to low arterial O2that may accompany underlying disease

Question 41

what is the treatment of polycythemia?

Answer 41

Many patients develop thromboses due to the increased blood viscosity and elevated platelet count •Primary Polycythemia: drugs that suppress bone marrow over - activity •Secondary Polycythemia: periodic removal of excess blood

Question 42

what is Hemochromatosis?

Answer 42

Genetic disease: autosomal recessive trait •Body becomes overloaded with iron •Iron is absorbed and excreted with difficulty

Question 43

what are the manifestations of hemochromatosis?

Answer 43

The manifestations of the disease take years to develop :tan to brown skin, diabetes, cirrhosis, heart failure can lead to organ damage

Question 44

what is the treatment for hemochromatosis?

Answer 44

Repeated phlebotomies(withdrawal of blood)until iron stores are depleted and then periodic for life

Question 45

what is secondary Thrombocytopenia Purpura

Answer 45

–Drugs, chemicals damage the bone marrow–Bone marrow infiltrated by leukemic cells ormetastatic carcinoma

Question 46

what is primary thrombocytopenia purpura?

Answer 46

–Associated with antiplatelet autoantibodies –The bone marrow produces platelets but are rapidly destroyed –Often encountered in children and subsides spontaneously after a short time–Tends to be chronic in adults

Question 47

what are the factors involved in controlling the balance?

Answer 47

Haemopoeitic Growth Factors ( Erythropoietin& Granulocyte colony – stimulating factor)

Question 48

what is Erythropoietin? and where is it produced?

Answer 48

Produced in juxtatubular cells in the kidney and also macrophages •Regulate red cell production

Question 49

Recombinant human erythropoietin can be admisitered IP? TRUE OR FALSE?

Answer 49

FALSE- only IV AND SC

Question 50

What is erytheropoietin used for?

Answer 50

Anaemia of chronic renal failure –Chemotherapy of cancer –Preventing anaemia in premature infants –anaemia of AIDS ( exacerbated byZidivudine) –Anaemia of chronic inflammatoryconditions such as rheumatoid arthritis

Question 51

what is a granulocyte colony?

Answer 51

* Stimulate neutrophil progenitors * Produced mainly by monocytes, fibroblasts and endothelial cells * Control development of neutrophils