Brainscape's Knowledge GenomeTM

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


See full index

Clinical lectures: Yr2 > Haemolytic Anaemia > Flashcards

Haemolytic Anaemia Flashcards

1
Q

What is haemolysis?

A

Erythrocyte breakdown before their normal 120-day lifespan

Haemolysis leads to a decrease in the number of red blood cells in circulation.

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

Define haemolytic anaemia

A

Form of anaemia that occurs when erythrocyte destruction happens at a faster rate than erythropoiesis

It is characterized by reduced erythrocyte production or increased breakdown.

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

What is erythropoietic hyperplasia?

A

Increased RBC production in the bone marrow at 6-8x normal rate

This occurs in response to increased destruction of erythrocytes.

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

List the laboratory findings associated with haemolytic anaemia

A
  • Elevated reticulocyte count (reticulocytosis)
  • Elevated lactate dehydrogenase
  • Low haptoglobin
  • Elevated unconjugated bilirubin
  • Blood film: polychromasia, nucleated erythrocytes

These findings help diagnose the condition.

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

What does elevated reticulocyte count indicate?

A

Increased RBC production in response to haemolysis

Reticulocytosis is a common finding in haemolytic anaemia.

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

What causes low haptoglobin levels in haemolytic anaemia?

A

Haptoglobin binds to free Hb released from dead/damaged erythrocytes and is used up faster than it can be produced by the liver

This is a key laboratory finding in diagnosing haemolytic anaemia.

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

What are common signs of haemolysis?

A
  • Dark urine
  • Jaundice (yellow sclera and skin)
  • Gallstones with RBC pigment
  • Anaemic signs (more common in acute haemolysis)

Dark urine is due to bilirubin conversion to urobilinogen.

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

What does a blood film show in haemolytic anaemia?

A

Normocytic or macrocytic erythrocytes due to raised reticulocyte count

Polychromasia and nucleated erythrocytes may also be observed.

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

What is paroxysmal nocturnal haemoglobinuria?

A

Acquired, rare form of intravascular haemolysis due to absence of glycosylphosphatidylinositol (GPI)

This absence leads to a lack of surface proteins that protect erythrocytes from complement-mediated lysis.

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

What are the symptoms of paroxysmal nocturnal haemoglobinuria?

A
  • High level of free Hb in blood
  • Dark urine
  • Increased risk of clot formation in unusual areas

These symptoms occur due to the breakdown of erythrocytes.

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

True or False: Gallstones with RBC pigment are more common in chronic haemolysis.

A

True

This is a result of persistent breakdown of red blood cells.

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

Fill in the blank: The protein produced in the liver that binds to free hemoglobin is called _______.

A

haptoglobin

Haptoglobin levels decrease in haemolytic conditions.

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

What are Haemaglobinopathies?

A

Inherited abnormalities of hemoglobin that can affect red blood cell function.

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

What are Membranopathies?

A

Inherited abnormalities characterized by erythrocytes that can’t maintain biconcave shape, making them more susceptible to damage and resulting in a shorter lifespan due to early macrophage removal in the spleen.

Examples include Hereditary Spherocytosis (HS), Hereditary Elliptocytosis (HE), and Hereditary Stomatocytosis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How is Hereditary Spherocytosis (HS) treated?

A

Treated with folic acid supplementation and splenectomy.

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

What investigations are done for Membranopathies?

A

Investigations include family history, genetic testing (usually autosomal dominant), abnormal blood film, haemolysis screen, and specialist tests.

Tests show elevated bilirubin, elevated reticulocyte count, and elevated LDH, with a negative Coombe’s test indicating erythrocytes aren’t coated in antibody.

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

What are the clinical presentations of Membranopathies?

A

Clinical presentation includes prolonged neonatal jaundice, mild anemia at any age, fluctuating jaundice worse during infections, pigment gallstones, and aplastic crisis caused by parvovirus (B19).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are Enzymopathies?

A

Disorders caused by enzyme deficiencies affecting red blood cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the most common Enzymopathy?

A

The most common is G6PD deficiency.

It is usually X-linked recessive.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the epidemiology of G6PD deficiency?

A

Common in people with Mediterranean and African ancestry.

21
Q

What is the effect of G6PD deficiency on erythrocytes?

A

Erythrocytes can’t produce much NADPH for glutathione regeneration, making the RBC membrane unstable against oxidative stress caused by hydrogen peroxide.

22
Q

What typically triggers hemolysis episodes in G6PD deficiency?

A

Hemolysis episodes are usually triggered by oxidative stress caused by drugs, infections, mothballs, and fava beans.

23
Q

What are the extrinsic causes of haemolysis?

A

Extrinsic causes of haemolysis include antibody attack, specifically Autoimmune Haemolytic Anaemia (AIHA).

24
Q

What happens to erythrocytes in AIHA?

A

Erythrocytes will be coated by either IgM or IgG antibodies.

25
Q

What does a blood film show in IgM mediated AIHA?

A

Blood film shows agglutination.

26
Q

What does a blood film show in IgG mediated AIHA?

A

Blood film shows spherocytes.

27
Q

What is the main investigation for AIHA?

A

The main investigation is the Direct Coombe’s (antiglobulin) test.

28
Q

What indicates a positive Direct Coombe’s test?

A

Agglutination occurs when anti-human antibody is added to the patient sample of RBCs.

29
Q

What characterizes warm AIHA?

A

Warm AIHA occurs when antibodies react with RBCs at 37°C, usually involving IgG.

30
Q

What are common causes of warm AIHA?

A

Common causes include idiopathic reasons, autoimmune conditions, immune disorders like low-grade lymphoma or Chronic Lymphocytic Leukaemia (CLL), and medications like penicillin and methyldopa.

31
Q

What is the result of warm antibodies in AIHA?

A

Warm antibodies lead to extravascular haemolysis in the spleen and liver.

32
Q

What characterizes cold AIHA?

A

Cold AIHA occurs when antibodies react with RBCs below 37°C, usually involving IgM.

33
Q

What are common causes of cold AIHA?

A

Common causes include idiopathic reasons, low-grade lymphomas, and infections like mycoplasma pneumonia and EBV.

34
Q

What is Paroxysmal cold haemoglobinuria?

A

It is a rare form of cold AIHA where IgG antibody binds to erythrocytes in the cold but causes haemolysis in warm temperatures.

35
Q

What are the management strategies for AIHA?

A

Management includes treating the underlying cause, keeping the patient warm for cold AIHA, folic acid supplements, immunosuppressants, and splenectomy for most warm cases.

36
Q

What is the treatment for cold AIHA?

A

Keep the patient warm and consider warming blood to be transfused.

37
Q

What is the role of folic acid in AIHA management?

A

Folic acid supplements can be given, and folic acid transfusion may be necessary if haemolysis onset is acute.

38
Q

What immunosuppressants are used for AIHA?

A

Rituximab is used for cold/warm haemolysis, and high dose corticosteroids are used for warm haemolysis.

39
Q

What surgical intervention is often needed for warm AIHA?

A

Most warm cases require splenectomy.

40
Q

What is microangiopathic haemolytic anaemia?

A

It is caused by narrowing or obstruction of small blood vessels, leading to intravascular haemolysis.

Examples include Thrombotic thrombocytopenic purpura (TTP), Disseminated intravascular coagulation (DIC), and Haemolytic Uremic Syndrome (HUS).

41
Q

What is Thrombotic thrombocytopenic purpura (TTP)?

A

A rare blood disorder that results in blood clots forming in small blood vessels.

42
Q

What is Disseminated intravascular coagulation (DIC)?

A

A rare blood disorder in which the proteins that control blood clotting become overactive.

43
Q

What can cause repeated mechanical trauma to capillaries?

A

Faulty mechanical heart valves or march haemoglobinuria, which involves repeated force on capillaries in the feet.

44
Q

What are the main investigations for microangiopathic haemolytic anaemia?

A

Urine tests positive for Hb and a negative Coombe’s test, along with a blood film showing schistocytes (fragmented erythrocytes).

45
Q

What infections can cause haemolysis?

A

Infections such as malaria can destroy erythrocytes.

46
Q

What are some chemical and physical agents that can cause haemolysis?

A

Lead, burns, snake and spider bites, and drugs such as dapsone.

This is a rare cause of haemolysis.

47
Q

What is the gold standard investigation for diagnosis of PNH?

A

Flow cytometry: CD55 and CD59 negative red and white blood cells

Patient also has characteristic presentation: Blood in urine/dark urine in the morning after waking up

48
Q

What biologic is used to treat PNH?

A

Eculizumab

49
Q

What is methemoglobinemia and give 3 signs?

A

Presence of methaemoglobin, a form of haemoglobin in which the iron ion (Fe2+) is oxidised to the ferric state (Fe3+)

Lethargy, hypoxia, cyanosis

Clinical lectures: Yr2 (41 decks)

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