Haem

Question 1

Which organisms most commonly cause neutropenic sepsis?

Answer 1

Coagulase -ve gram +ve bacteria

particularly staph epidermis

Question 2

What are auer rods? what conditions are they seen in?

Answer 2

Large, pink / red needle shaped structures in cytoplasm of myeloid cells

Seen in AML
Also in APML, high grade myelodysplastic syndromes and myeloproliferative disorders

Question 3

What are some features of APML?

Answer 3

Presents younger than other forms of AML (avg 25yrs)

DIC / Thrombocytopaenia at presentation

Good prognosis

Question 4

Genetic cause of APML

Answer 4

t(15;17) translocation - fusion of PML and RAR-alpha genes –> blocks the maturation of myeloid cells and leads to an accumulation of promyelocytes.

Question 5

APML mx?

Answer 5

Treated with all-trans retinoic acid (ATRA) -> forces immature granulocytes into maturation to resolve blast criseses prior to definitive chemo

Question 6

Bloods in DIC?

Answer 6

↓ platelets

↓ fibrinogen

↑ PT & APTT

↑ fibrinogen degradation products

schistocytes due to microangiopathic haemolytic anaemia

Question 7

How can you distinguish between Waldenstrom’s macroglobulinaemia and multiple myeloma?

Answer 7

Waldenstrom’s macroglobulinaemia - Organomegaly with no bone lesions

Multiple myeloma - Bone lesions with no organomegaly

Question 8

What are some features of Waldenstroms macroglobulinaemia?

Mx?

Answer 8

systemic upset: weight loss, lethargy
hyperviscosity syndrome e.g. visual disturbance (the pentameric configuration of IgM increases serum viscosity)
hepatosplenomegaly
lymphadenopathy
cryoglobulinaemia e.g. Raynaud’s

Mx - rituximab based combination chemo

Question 9

Ix findings for waldenstrom’s macroglobulinaemia?

Answer 9

Monoclonal IgM paraproteinaemia (M - Macroglobulinaemia)

BM biopsy - diagnostic - infiltration of BM with lymphoplasmacytoid lymphoma cells

Question 10

What genetic abnormality is associated with chronic myeloid leukaemia (CML)?

Answer 10

Philidelphia chromosome - t(9;22)
seen in 95% of cases

NB also seen in 25% of adults with ALL - poor prognostic feature in these cases

Question 11

What genetic abnormality is seen in Burkitt’s lymphoma?

Answer 11

t (8;14) seen in Burkitt’s lymphoma

MYC oncogene is translocated to an immunoglobulin gene

Question 12

What genetic abnormality is seen in Mantle cell lymphoma?

Answer 12

t(11;14) is seen in mantle cell lymphoma

deregulation of BCL-1 gene

Question 13

What genetic abnormality is seen follicular lymphoma?

Answer 13

t(14;18) - increased BCL-2 transcription

Question 14

What are some intravascular causes of haemolytic anaemia?

Answer 14

mismatched blood transfusion
G6PD deficiency*
red cell fragmentation: heart valves, TTP, DIC, HUS
paroxysmal nocturnal haemoglobinuria
cold autoimmune haemolytic anaemia

Question 15

Extravascular causes of haemolysis

Answer 15

haemoglobinopathies: sickle cell, thalassaemia
hereditary spherocytosis
haemolytic disease of newborn
warm autoimmune haemolytic anaemia

Question 16

What does haptoglobin do?

Answer 16

Binds to free Hb which is released in intravascular haemolysis - hence depleted in intravascular causes

Question 17

What happens to free Hb once haptoglobin is saturated? how is this detected?

Answer 17

As haptoglobin becomes saturated haemoglobin binds to albumin forming methaemalbumin (detected by Schumm’s test).

Question 18

Bloods in Warfarin?

Answer 18

PT - Prolonged

APTT - Normal
Bleeding time - Normal
Plts - Normal

Question 19

Bloods in Aspirin use?

Answer 19

Bleeding time - prolonged

PT - Normal
APTT - Normal
Plts - Normal

Question 20

Bloods in heparin use?

Answer 20

APTT - Prolonged
PT - Normal (usually) / prolonged

Bleeding time - normal
Plts - Normal