Aplastic Anaemia + Polycythaemia

Question 1

How common is Aplastic anaemia

Answer 1

Rare

Question 2

Defining features of aplastic anaemia

Answer 2

1. Pancocytopenia (reduction in all major cell lines, RBC, WBC and platelets)
2. Hypocellularity (aplasia of bone marrow)

Question 3

Main causes of aplastic

Answer 3

1. Inherited
2. Idiopathic acquired (67%)
3. Benzene, toluene, glue sniffing
4. Chemotherapeutic drugs
5. Antibiotics
6. Infections

Question 4

Pathophysiology of Aplastic anaemia

Answer 4

1. Reduction in pluripotent stem cells together with a fault in those remaining or an immune reaction against them so they are unable to repopulate bone marrow

Question 5

Clinical presentation of aplastic anaemia

Answer 5

1. Anaemia
2. Increased susceptibility to infection
3. Bleeding
4. Bleeding gums, bruising with minimal trauma and blood blisters in the mouth

Question 6

What can aplastic anaemia be mistaken for

Answer 6

NHL

Myeloma

Question 7

Blood count in aplastic

Answer 7

Pancocytopenia + low reticulocyte count

Question 8

Bone marrow examination aplastic

Answer 8

Hypocellular marrow + increased fat spaces

Question 9

How is aplastic treated

Answer 9

1. Antibiotics urgently to prevent infections
2. Red cell and platelet transfusion
3. Bone marrow transplant

Question 10

Describe immunosuppressive therapy after bone marrow transplant for aplastic anaemia

Answer 10

1. ANTHITHYMOCYTE GLOBULIN and CICLOSPORIN

in over 40 or below 40 with severe disease + no HLA identical donor

Question 11

What is polycythaemia

Answer 11

Increase in Hb, haematocrit and red cell count (all conc.)

Question 12

Why is PCV a more reliable indicator of polycthaemia than Hb

Answer 12

Disproportionally low in iron deficiency

Question 13

What can Polycythaemia be divided into

Answer 13

ABSOLUTE (increase in RBC mass) +RELATIVE (decreased plasma vol + normal RBC mass)

Question 14

What is PRIMARY ABSOLUTE POLYCYTHAEMIA

Answer 14

1. P. VERA
   MUTATIONS IN ERYTHROPOIETIN RECEPTOR
   HIGH OXYGEN AFFINITY Hbs

Question 15

What is SECONDARY ABSOLUTE POLYCYTHAEMIA

Answer 15

1. Hypoxia

2. High erythropoietin secretion

Question 16

What is APPARENT POLYCYTHAEMIA

Answer 16

Chronic form associated with obesity, hypertension + high alcohol and tobacco intake

Question 17

How is Polycythaemia Vera caused

Answer 17

Acquired mutations of gene JAK2

Question 18

How is Polycythaemia vera caused genetically

Answer 18

1. Point Mutation that causes the substitution of phenylalanine for valine at position 617

Question 19

Role of JAK2

Answer 19

Cytoplasmic tyrosine kinase that induces signals, especially those triggered by haematopoietic growth factors such as erythropoietin

Question 20

What age group does polycythaemia vera effect

Answer 20

Over 60

Question 21

Pathophysiology caused by mutation of JAK2

Answer 21

1. A clonal stem disorder resulting in a malignant proliferation of a clone derived from one pluripotent marrow stem cell

Question 22

What is polycythemia vera

Answer 22

Bone marrow makes too many RBCs, WBCs and platelts

Question 23

How does PV effect the bloodviscocity

Answer 23

Thicker as RBC population is larger

Question 24

Do erythroid progenitor offspring need erythropoietin to avoid apoptosis

Answer 24

No

Question 25

Complications of PV

Answer 25

1. Thrombosis | 2. Haemorrhage

Question 26

If PV is asymptomatic, how is polycythemia diagnosed

Answer 26

Detected on FBC

Question 27

What aged people are effected by PV

Answer 27

Over 60

Question 28

Symptoms caused by hyperviscoity

Answer 28

1. Headaches 2. Itching 3. Tiredness 4. Dizziness 5. Tinnitus 6. Visual Disturbances

Question 29

Specific symptoms of PV

Answer 29

1. Severe itching after a hot bath or when patient is warm 2. Erythromelalgia 3. Gout due to increased turnover may be a feature 4. Angina 5. Intermittent Claudication 6. Plethoric complexion 7. Hepatosplenomegaly

Question 30

What is erythromelalgia

Answer 30

Burning sensation in fingers and toes

Question 31

Why does PV result in gout

Answer 31

Increased turnover may be a feature

Question 32

What is plethoric complexion

Answer 32

Congested or swollen with blood in facial skin

Question 33

What causes hepatosplenomegaly

Answer 33

Extra medullary haemopoiesis DISTINGUISHES PV from secondary causes

Question 34

What would blood count show in PV

Answer 34

1. Raised WBC + platelets (distinguishes PV from secondary causes) Raised Hb Serum erythropoietin low

Question 35

What would genetic screening in PV show

Answer 35

JAKE2 mutation

Question 36

What would bone biopsy show in PV

Answer 36

Prominent erythroid Granulocytic Megakaryocytic proliferation

Question 37

How can PV be treated

Answer 37

1. No cure 2. Treatment to maintain a normal blood count 3. ASPIRIN with all treatments

Question 38

Surgical treatment PV

Answer 38

1. Lowers PCV and normal count Removes 400-500mL of blood weekly to relieve symptoms

Question 39

Chemotherapy treatment in PV

Answer 39

1. HYDROXYCARBAMIDE 2. BULSULFAN 3. ALLOPURINOL

Question 40

When is chemotherapy for PV given

Answer 40

Do not tolerate venesection or poorly controlled features of the disease

Question 41

When is radioactive phosphorus given for PV

Answer 41

Only in those over 70 due to increased risk of acute leukaemia

Question 42

Why is allopurinol given for PV

Answer 42

Block uric acid production thereby reduce gout