17. Haemolytic Anaemia

Question 1

What are the causes of anaemia?

Answer 1

Failure to make RBCs
Lack haematinics
Increased loss of RBCs
Chronic disease

Question 2

What is haemolytic anaemia?

Answer 2

Increased breakdown in RBCs

Bone marrow compensates, so increased reticulocyte count

Question 3

How can haemolytic anaemia be determined by blood tests?

Answer 3

High lactate dehydrogenase and bilirubin

Question 4

What happens in autoimmune haemolytic anaemia?

Answer 4

Self-antigens cause destruction of the RBCs
Warm= IgG
Cold= IgM

Question 5

Why are autoimmune anaemias classified as warm and cold?

Answer 5

Correlates to the temperature the antigen binds at

Question 6

What cases might an alloimmune reaction occur in?

Answer 6

Haemolytic transfusion
Disease of the newborn
Post bone marrow transplant

Question 7

What drug can induce haemolytic anaemia?

Answer 7

Dapsone

Question 8

What diseases can haemolytic anaemia be related to?

Answer 8

Lymphoma
Mycoplasma infection
Lupus
Paraneoplastic syndrome

Question 9

What test is used to detect IgG and IgM antibodies?

Answer 9

Coombe’s test

Question 10

Give some reasons for non-immune acquired haemolytic anaemia?

Answer 10

Fragmentation syndromes (eclampsia, sepsis, DIC)
Prosthetic heart valves

Question 11

What congenital defects can cause non-immune haemolytic anaemia?

Answer 11

Membrane abnormalities
Enzyme defects
Haemoglobin defects

Question 12

What membrane abnormality can cause haemolytic anaemia?

Answer 12

Structural protein of RBC membrane defect causes spherocytes

Question 13

Which enzyme defect causes haemolytic anaemia?

Answer 13

G6PD

Question 14

What haemoglobin defects cause haemolytic anaemia?

Answer 14

Sickle cell

Thalassaemia

Question 15

What mutation causes sickle cell anaemia?

Answer 15

Glutamic acid to valine

Question 16

What sort of inheritance is present in sickle cell anaemia?

Answer 16

AR

Question 17

What situations cause an increase in sickling?

Answer 17

Hypoxia
Acidosis
Hypotension
Infection
Dehydration
Hypothermia

Question 18

Why are gram - infections common in sickle cell anaemia?

Answer 18

People with sickle cell anaemia tend to be hyposplenic

Question 19

What complications are associated with sickle cell anaemia?

Answer 19

Osteomyelitis
Gall stones
Renal failure
Cardiac failure
Chronic leg ulcers

Question 20

What causes osteomyelitis, renal failure and chronic leg ulcers in sickle cell anaemia?

Answer 20

Infarction

In osteomyelitis this leads to infection

Question 21

What causes gall stones in sickle cell anaemia?

Answer 21

High bilirubin

Question 22

What causes cardiac failure in sickle cell anaemia?

Answer 22

Increased stress on the heart to oxygenate

Question 23

What is marrow fibrosis?

Answer 23

Response to cell death or tumour infiltration in the marrow

Results in scarring

Question 24

What are the causes of marrow fibrosis?

Answer 24

Metastases
Chemo
Radio
Drugs
Primary myelofibrosis

Question 25

What is the issue with haemoglobin in thalassaemia?

Answer 25

One globin chain is underproduced and the other is overproduced
The overproduced chains stick together and damage RBCs

Question 26

Why is there variation in severity with thalassaemia?

Answer 26

4 genes encode globin chains
1-2 genes deleted= mild anaemia
3= splenomegaly and severe anaemia
4= hydrops fetalis

Question 27

What are the lab results for thalassaemia?

Answer 27

Severe anaemia
Immature cells
Hypochromic microcytic cells
DNA test needed to confirm

Question 28

How are haemolytic anaemias managed?

Answer 28

Regular transfusion
Iron chelation
Splenectomy
Immunisation
Bone marrow transplant

Question 29

What are the potential effects of haemolysis?

Answer 29

Anaemia
Hyperbilirubinaemia
Effects of blood transfusions
Extra medullary haemopoiesis (splenomegaly)