Clinical haematology and oncology

Question 1

What is the most common tumour of the anterior mediastinum?

Answer 1

Thymoma

Question 2

What conditions are associated with Thymoma? (5)

Answer 2

1) Myasthenia Gravis (30-40%)
2) Red cell aplasia
3) Dermatomyositis
4) Systemic Lupus Erythematosus
5) SIADH

Question 3

What underlying pathophysiology is implicated in Methaemoglobinaemia?

Answer 3

Oxidation of Fe2 to Fe3 in haem subunits, which causes O2 to be unable to bind

Question 4

What clinical features are seen in Methaemoglobinaemia? (5)

Answer 4

1) Cyanosis
2) Signs/Symptoms consistent with reduced O2 delivery (chest pain/dyspnoea etc)
3) SpO2 85-90%
4) Blood samples will have a “chocolate brown” hue
5) Normal PaO2

Question 5

What are the congenital causes of methaemoglobinaemia? (2)

Answer 5

1) Cytochrome b5 reductase deficiency

2) Haemoglobin M Disease

Question 6

What are the acquired causes of Methaemoglobinaemia? (8)

Answer 6

1) Aniline dyes
2) Benzene derivatives
3) Chloroquine
4) Dapsone
5) Prilocaine
6) Metoclopramide
7) Nitrites
8) Sulphonamides

Question 7

What are the treatment options for methaemoglobinaemia? (2)

Answer 7

1) Avoid precipitants
2) Methylene blue

Question 8

What is the most common form of hereditary haemolytic anaemia in people of Northern European descent?

Answer 8

Hereditary spherocytosis

Question 9

What is the inheritance pattern of hereditary spherocytosis?

Answer 9

Autosomal dominant

Question 10

What shape of cell is seen in hereditary spherocytosis?

Answer 10

Sphere-shaped cell, as opposed to the normal biconcave disc shape

Question 11

What are the clinical features of hereditary spherocytosis? (6)

Answer 11

1) Jaundice & Gallstones
2) Failure to thrive
3) Splenomegaly
4) Aplastic crisis precipitated by parvovirus infection
5) Variable degrees of haemolysis
6) Raised MCHC

Question 12

What 3 features should be present to form a diagnosis of hereditary spherocytosis without further testing?

Answer 12

1) Fix
2) Typical clinical features being present
3) Typical laboratory findings (Spherocytes, Raised MCHC, increased reticulocytes)

Question 13

What diagnostic test should be run when querying hereditary spherocytosis?

Answer 13

Electrophoresis analysis of erythrocyte membranes

Question 14

What is the management of acute haemolytic crisis in patients with hereditary spherocytosis?

Answer 14

Mainly supportive, however blood transfusion can be considerd

Question 15

What is the long-term management of patients with hereditary spherocytosis?

Answer 15

1) Folate replacement
2) Splenectomy