H1 - Anaemia

Question 1

what is anaemia

Answer 1

low Hb levels

Question 2

What are the 3 main predisposing factors of anaemia

Answer 2

• ↓ production RBCs
• ↑ destruction of RBCs
• loss of RBCs (bleeding)

Question 3

what 4 things cause ↓ production RBCs, causing anaemia

Answer 3

iron deficiency
B12 or folate deficiency
marrow infiltration (cancer)
chronic disease (rheumatoid, cancer)

Question 4

what can cause ↑ destruction of RBCs, causing anaemia

Answer 4

• disorders of RBC membrane/enzyme/Hb

- immune destruction

Question 5

what are the types of classification of anaemias

Answer 5

inherited vs acquired
microcytic, normocytic, macrocytic
immune vs non-immune

Question 6

What are the sizes of micro, normo and macrocytic RBCs

Answer 6

<76 = microcytic
76 -96 = normocytic
>96 macrocytic

Question 7

what are causes of microcytic anaemia

Answer 7

iron deficiency

thalassaemia ( ↓ Hb disease)

Question 8

what causes iron deficiency anaemia

Answer 8

defective Hb synthesis

• results in small RBCs (microcytic) - reduced RBC maturation- variable sizes
• contains ↓ amounts of Hb (hypochromic/paler)

Question 9

what are the factors that enhance iron absorption

Answer 9

haem iron (meat)
ferrous salts (Fe2+)
acid pH
iron deficiency
pregnancy
hypoxia

Question 10

what are the factors that impair iron absorption

Answer 10

non-haem iron (veg)
ferric salts (Fe3+)
alkaline pH
iron overload
inflammatory disorders

Question 11

how do you confirm iron deficiency

Answer 11

1. full blood count
2. blood film
3. ↓ serum ferritin (storage iron)
4. ↓ serum iron
5. ↑ transferrin saturation

Question 12

what can be the causes of iron deficiency which will then cause anaemia

Answer 12

menorrhagia

males = GIT bleeding (ulcer, cancer)

Question 13

what is the best way to treat iron deficiency

Answer 13

replace iron
diet
oral iron ( supplements)
avoid blood transfusion

Question 14

What causes of normocytic anaemias are there

Answer 14

cancer
chronic disease
acute blood loss
renal disease
haemolysis (destruction of rbcs)

Question 15

what are types of marrow infiltration (cancer) that can cause anaemia

Answer 15

• metastatic cancer (breast, prostate, lung, thyroid renal, any)
• myeloma
• myelofibrosis
• leukaemia + lymphoma

Question 16

what is the cause of anaemia of chronic disease

Answer 16

• chronic inflammation, infection or cancer

- caused by inflammatory cytokines

Question 17

what happens in anaemia of chronic disease

Answer 17

• ↓ RBC lifespan
• poor marrow response to Epo (erythropoietin = hormone helps make RBC)
• depressed erythropoiesis
• inflammatory cytokines
• interfere with Epo production + actions

Question 18

what treatment would you give to someone with anaemia of chronic disease

Answer 18

find underlying cause

Erythropoietin to stimulate RBC release

Question 19

what are the 7 main causes of macrocytic anaemia

Answer 19

1. B12 or folate deficiency(megaloblastic)
2. liver disease
3. alcohol
4. haemolytic if reticulocytosis (↑ immature RBCs)
5. bone marrow failure
6. myelodysplasia (blood cancer)
7. drugs (chemo, anticonvulsants )

Question 20

how does vit b12 + folate deficiency cause macrocytic anaemia

Answer 20

• B12 + folate needed for DNA synthesis
• DNA synthesis impaired
• cells fail to divide
• large cells

Question 21

what causes the large size of the megaloblastic (macrocytic) rbc in megaloblastic anaemia

Answer 21

• delayed maturation of nucleus of erythroblasts
• due to defective DNA synthesis
• due to B12/ folate deficiency

Question 22

what are the causes of b12 deficiency

Answer 22

nutrition
malabsorption
gastric - total/partial gastrectomy
intestinal - stagnant loop syndromes, Ileal disease, tapeworm

Question 23

What is pernicious anaemia, who is normally affects and what causes it

Answer 23

• b12 deficiency
• fair hair, blue eyes, blood grp A
• Autoantibody against gastric mucosa + intrinsic factor (IF)
• leads to gastric atrophy, ↓acid + ↓ IF secretion

Question 24

What are clinical features that can be seen with someone with pernicious anaemia

Answer 24

• Insidious
• anaemia
• glossitis
• mild jaundice
• peripheral neuropathy
• post + lat column damage
• dementia
• optic atrophy

Question 25

What are clinical neurology features that can be seen with someone with pernicious anaemia

Answer 25

- peripheral neuropathy - post + lat column damage - dementia - optic atrophy

Question 26

what is the treatment for pernicious anaemia

Answer 26

IM B12 every 3 months for life

Question 27

What are the causes of folate deficiency

Answer 27

- nutrition = age, alcholism, poverty malabsorption - Coeliac, Crohn's - anticonvulsants

Question 28

What are clinical features that can be seen with someone with folate deficiency

Answer 28

- insidious - anaemia - glossitis - mild jaundice - NO NEUROLOGY

Question 29

what is the difference between b12 deficiency + folate deficiency in clinical features

Answer 29

b12 deficiency - neurology affected but in folate deficiency no neurology affected

Question 30

what is the treatment for folate deficiency

Answer 30

oral folic acid

Question 31

what is haemolytic anaemia

Answer 31

anaemia due to shortened RBC survival (<120 days)

Question 32

what are the main features of haemolysis

Answer 32

1. membrane 2. Hb 3. enzymes

Question 33

what are the abnormalities of the RBC in haemolytic anameias

Answer 33

``` 1. membrane antibodies against RBC membrane alloantibodies 2. Hb abnormal structure (sickle) thalassaemia 3. ↓ glucose-6-phosphate dehydrogenase ```

Question 34

how does haemolytic anaemia present itself

Answer 34

- pallor + anaemia - jaundice - gallstones - splenomegaly

Question 35

explain hereditary spherocytosis

Answer 35

Hereditary spherocytosis autosomal dominant spherocytes in peripheral blood they are weird shape so get destroyed more quickly

Question 36

what are spherocytes

Answer 36

RBCs but sphere shaped instead of disc - more fragile

Question 37

explain G6PD deficiency

Answer 37

- G6PD reverses oxidation of Hb, -> destruction of membrane | - x linked

Question 38

what are the clinical features of G6PD Deficiency

Answer 38

neonatal jaundice acute haemolysis with oxidant drugs fava beans

Question 39

explain what happens in sickle cell

Answer 39

``` - point mutation When ↓O2 - Hb forms long rod structures - RBCs sickle - ↑ rigid block microcirculation - ischaemia - pain ```

Question 40

describe the autoimmune haemolytic anaemia antibody

Answer 40

self reacting IgG antibody attaches to RBC removed by spleen (extravascular haemolysis)

Question 41

How do you prove there is a antibody on the cell

Answer 41

Direct Coombs test 1. blood with human anti-RBC antibody - attached to antigens 2. patient's RBCs incubated with antihuman antibodies (Coombs reagent) 3. RBCs agglutinate. Reagent antibodies forms links to human RBCs using human antibodies

Question 42

what are some causes of immune haemolytic anaemia

Answer 42

drugs (penicillin) cancer blood transfusion connective tissue disease

Question 43

how do you investigate anaemia in general

Answer 43

1. history + examination (drugs, family, lymph nodes) 2. repeat FBC + see blood film 3. Check serum B12, folate + ferritin 4. renal + liver function 5. ESR (checks inflammation/diseases)

Question 44

describe the lab features of haemolytic anaemia

Answer 44

``` ↓Hb ↑ reticulocytes ↑LDH ↑ bilirubin ↑ urinary B haptoglobin ```

Question 45

What are the 3 things that can cause congenital haemolytic anaemia

Answer 45

- RBC membrane ( hereditary spherocytosis) - Hb structure (sickle cell, thalassaemia) - enzyme deficiency ↓ G6PD)

Question 46

What are the 2 things that can cause acquired haemolytic anaemia

Answer 46

immune mediated - primary./secondary | mechanical - heart valves

Question 47

what does immune mediated mean

Answer 47

immune system is responsible for destruction of RBCs, can be primary or secondary