Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Haematology SB > Haemolysis > Flashcards

Haemolysis Flashcards

1
Q

what is haemolysis

A

Premature red cell destruction

i.e. shortened red cell survival

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

why are red cells susceptible to damage

A
  1. need a biconcave shape to transit the circulation
  2. limited metabolic reserve and rely on glucose metabolism for energy (no mitochondria)
  3. Can’t generate new proteins once in the circulation (no nucleus)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is compensated haemolysis

A

Increased red cell destruction compensated by increased red cell production
i.e. Hb Maintained

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is decompensated haemolysis also known as

A

Haemolytic anaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is haemolytic anaemia

A

Increased rate of red cell destruction exceeding bone marrow capacity for red cell production
i.e. Hb Falls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are consequences of haemolysis

A

Erythroid hyperplasia (increased bone marrow red cell production)

Excess red cell breakdown products eg billirubin (clinical features differ by aetiology and site of red cell breakdown)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the bone marrow response to haemolysis

A

1 - reticulocytosis

2 - erythroid hyperplasia [see a higher number of precursors of RBC in the bone marrow]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what special stain can be used to just see reticulocytes on a blood film

A

supravital stain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how can haemolytic anaemia be classified

A

extravascular
- RBC destroyed by spleen and liver

intravascular
- RBC destroyed within the circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what form of haemolytic anaemia is more common

A

extravascular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are features of extravascular haemolytic anaemia

A

splenomegaly +/- hepatomegaly

Release of protoporphyrin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what does release of protoporphyrin cause

A

Unconjugated bilrubinaemia
> Jaundice and Gall stones

Urobilinogenuria

Normal products

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what does it mean if bilirubin is unconjugated

A

pre hepatic cause

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the pathophysiology of intravascular haemolysis

A

Red cells are destroyed in the circulation spilling their contents.

  1. Haemoglobinaemia (free Hb in circulation)
  2. Methaemalbuminaemia
  3. Haemoglobinuria: pink urine, turns black on letting the urine stand
  4. Haemosiderinuria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the big difference in symptoms between extra and intra vascular haemolysis

A

intravascular cause ABNORMAL products

- may be life threatening

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are causes of intravascular haemolysis

A

ABO incompatible blood transfusion

G6PD deficiency

Severe falciparum malaria
(Blackwater Fever)

PNH,PCH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what Ix are done first in haemolytic anaemia

A 
FBC (+ BLOOD FILM)
Reticulocyte count
Serum unconjugated bilirubin
Serum haptoglobins
Urinary urobilinogen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what Ix are done second in haemolytic anaemia

A 
Blood Film: 
Membrane damage (spherocytes)
Mechanical damage (red cell fragments)
 Oxidative damage (Heinz bodies)
 Others e.g.. HbS (sickle cells)
19
Q

what is another way to classify haemolytic anaemia

A

by site of red cell defect

20
Q

what are the 4 types of haemolytic anaemia by site

A
  1. Premature destruction of normal red cells (immune or mechanical)
  2. Abnormal cell membrane
  3. Abnormal red cell metabolism
  4. Abnormal haemoglobin
21
Q

what are acquired immune haemolysis

A

autoimmune haemolysis

alloimmune haemolysis

22
Q

what are the subtypes of autoimmune haemolysis

A

warm (IgG)

cold (IgM)

23
Q

what are the cause of warm autoimmune haemolysis

A

idiopathic
autoimmune disorders (SLE)
Lymphoproliferative disorders (CLL)
Drugs (penicillins, etc) Infections

24
Q

what is the test for autoimmune haemolytic anaemia

A

direct Coombs test

25
Q

what are the two possible forms of alloimmune haemolysis

A

immune response (antibody produced)

passive transfer of antibody

26
Q

what can cause an immune response leading to haemolysis

A

Haemolytic transfusion reaction

  • Immediate (IgM) predominantly intravascular
  • Delayed (IgG) predominantly extravascular
27
Q

what can cause an passive transfer of antibody leading to haemolysis

A

Haemolytic disease of the newborn

28
Q

what are causes of mechanical red cell destruction

A 
DIC
HUS
TTP 
leaking heart valve 
infections e.g. malaria
29
Q

what seen in a blood film would be suggestive of a mechanical red cell destruction

A

red cell fragmentation

30
Q

what is seen in burns related haemolysis

A

Microspherocytes

- small spherocytes predominate and red blood cells are smaller and more globular than normal

31
Q

what are causes of acquired RBC membrane defects (rare)

A 
Liver Disease (Zieve’s Syndrome)
Vitamin E deficiency
Paroxysmal Nocturnal Haemoglobinuria
32
Q

what is Zieve’s syndrome

A

Haemolysis, Alcoholic liver disease, hyperlilidaemia

33
Q

what are causes of congenital RBC membrane defects

A

Hereditary Spherocytosis

34
Q

what are genetic causes of abnormal red cell metabolism

A

failure to cope with oxidant stress (G6PD deficiency - most common form)

failure to generate ATP: metabolic processes fail

35
Q

what can cause stress to the metabolic pathways in normal cells

A

dapsone or salazopyrin

36
Q

what does dapsone cause

A

bite cells a.k.a irregularly contracted cell

37
Q

what genetic disease can cause haemolytic anaemia by making abnormal haemoglobin

A

Sickle cell disease

38
Q

what are pappenheimer bodies and what are they seen in

A

abnormal granules of iron found inside red blood cells

beta thalassaemia major

39
Q

what type of haemolysis is seen in hereditary spherocytosis

A

Chronic extravascular haemolysis.

40
Q

what does the defect affect in hereditary spherocytosis

A

the RBC membrane flexibility

41
Q

what type of haemolysis is seen in Falciparum malaria

A

intravascular haemolysis

42
Q

what is seen on a blood film of HbH

A

inclusion bodies

- golf ball appearance

43
Q

what are Heinz bodies

A

Red cell inclusions comprised of denatured Hb normally removed by spleen (eg seen in G6PD deficiency)

Haematology SB (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions