Anaemia - Definition and Issues

Question 1

What is anaemia

Answer 1

A reduction in haemoglobin in the blood

Question 2

What is commonly mistaken for anaemia

Answer 2

Reduction in red blood cells

Question 3

What are the causes of anaemia

Answer 3

Reduced production of Hb
Increased loss of blood
Increased demand of Hb

Question 4

How can reduced normal red cells cause anaemia

Answer 4

Causes bone marrow failure so RBCs are unable to package Hb

Question 5

How can normal red cells but reduced Hb cause anaemia

Answer 5

Deficiencies of iron, folic acid or vitamin B12
Abnormal globulin chains causin thalassaemia or sickle cell
Chronic inflammatory disease

Question 6

What can cause bone marrow to become aplastic

Answer 6

Age or disease affecting bone marrow

Question 7

What are haematinics

Answer 7

Things used to make the red blood cells

Question 8

Give examples of haematinics

Answer 8

Iron
Folic acid (folate)
Vitamin B12

Question 9

What can cause iron loss

Answer 9

Gastric erosions and ulcers
Inflammatory bowel disease
Bowel cancer
Haemorrhoids

Question 10

Give examples of inflammatory bowel disease

Answer 10

Crohn’s disease

Ulcerative colitis

Question 11

Give examples of bowel cancers

Answer 11

Colonic cancer

Rectal cancer

Question 12

What are sources of iron

Answer 12

Meat
Leafy green vegetables
Iron tablets

Question 13

How is iron absorbed

Answer 13

Haem iron (Fe2+) is absorbed through a transporter system within intestinal cell wall
Non haem (Fe3+) can be absorbed but must be converted in to Fe2+ then absorbed through transporter system within cell wall
Stored as ferritin in cell, passed into blood and carried away for recirculating and reprocessing

Question 14

How is iron reprocessed

Answer 14

Reprocessed through macrophages then into the bone marrow through the haem processing system to allow new rbc’s to be manufactured with new Hb

Question 15

What happens to iron after it is reprocessed

Answer 15

Most iron is conserved but a small amount is absorbed everyday to make up for the small amount which is normally lost

Question 16

Which diseases reduce iron absorption

Answer 16

Achlorhydria

Coeliac disease

Question 17

What is achlorhydria

Answer 17

Lack of stomach acid so non-haem iron cannot be converted

May be due to disease or drug induced - Proton Pump Inhibitors

Question 18

What are sources of Vitamin B12

Answer 18

Dairy products and meats

Question 19

How is Vitamin B12 absorbed

Answer 19

Absorbed through complex process involving secretion of intrinsic factor by gastric parietal cells, binding of intrinsic factor to Vitamin B12 taken in through diet
Complex passes to terminal ileum and is absorbed through the transporting system

Question 20

What happens if the intrinsic factor - vitamin B12 complex isn’t formed

Answer 20

Absorption of Vitamin B12 alone isn’t possible
Liver will store a significant amount of Vitamin B12
Injections of Vitamin B12 will need to be given to the patient monthly

Question 21

What can cause folic acid deficiency

Answer 21

Lack of intake - peculiar dietary habits

Absorption failure caused by jejunal disease or coeliac disease

Question 22

What can folic acid deficiency cause

Answer 22

Neural tube defects in foetus such as spina bifida

Question 23

What is spina bifida

Answer 23

When a baby’s spine and spinal cord does not develop properly in the womb, causing a gap in the spine

Question 24

When is Alpha Hb produced

Answer 24

Throughout life

Question 25

When is beta Hb produced

Answer 25

After birth

Question 26

When is gamma Hb produced

Answer 26

Before birth, reduced after birth

Question 27

Where is Hb developed during pregnancy

Answer 27

Liver and spleen

Question 28

Where is Hb developed during and after birth

Answer 28

Bone marrow

Question 29

Why are changes in globin chain Hb production important

Answer 29

Gamma is more able to remove oxygen from maternal circulation for the baby’s need allowing a concentration gradient to filter oxygen from maternal circulation into the foetal circulation - this is no longer required when the baby can breath

Question 30

What is thalassaemia

Answer 30

Genetic mutation of globin chains | Occurs with normal Hb production

Question 31

What are the different types of thalassaemia

Answer 31

``` Alpha chains (alpha thalassaemia) - found most in Asian groups Beta chains (beta thalassaemia) - found most in Mediterranean groups ```

Question 32

What is important to remember about thalassaemia when examining a patient

Answer 32

Can appear in anyone due to genetic mixing through the years | Must be considered in any patient with consisting anaemia

Question 33

What are the clinical effects of thalassaemia

Answer 33

``` Chronic anaemia Marrow hyperplasia (skeletal deformities) Splenomegaly Cirrhosis Gallstones ```

Question 34

How can thalassaemia cause splenomegaly

Answer 34

Spleen is used to recycle RBC’s and as they are abnormal they do not last as long so turnover and reprocessing is higher

Question 35

How can thalassaemia cause cirrhosis

Answer 35

Due to excess iron

Question 36

How can thalassaemia cause gallstones

Answer 36

Haem reprocessing increases the levels of pigment chemicals passing through the liver

Question 37

How can thalassaemia be managed

Answer 37

Through blood transfusions | Prevent iron overload - they already have enough haem so giving more causes iron overload and cirrhosis

Question 38

What is sickle cell anaemia

Answer 38

When there aren’t enough RBC’s to carry oxygen throughout the body Due to abnormal globin chains - these function normally in standard oxygen environments Abnormal globin chains change shape in low oxygen environments - high altitude, during operations

Question 39

What does a change in shape of abnormal globin chains cause

Answer 39

Prevents RBC’s from passing through the capillaries | Tissue ischaemia - causes pain and necrosis

Question 40

What is ischaemia

Answer 40

Restriction of blood flow in a part of the body

Question 41

What is the difference between heterozygous and homozygous in sickle cell anaemia

Answer 41

If someone is heterozygous they have a sickle cell trait | If someone is homozygous they have sickle cell disease