Brainscape's Knowledge GenomeTM

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


See full index

Anaemia > Haemolytic Anaemia > Flashcards

Haemolytic Anaemia Flashcards

1
Q

Definition of haemolytic anaemia?

A

Anaemia due to the destruction of RBCs

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

Investigations for haemolytic anaemia?

A

FBC (shows increased reticulocytes)
Blood film - essential
Bilirubin - shows unconjugated hyperbilirubinaemia
Lactic dehydrogenase (LDH) - increased in haemolysis

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

Specific investigations?

A

Coomb’s Test
EMA-binding - for hereditary spherocytosis
Glucose-6-phosphate dehydrogenase assay - for G6PD deficiency
Haemoglobin electrophoresis - can be used in diagnosis of thalassaemia

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

What is the Coomb’s test?

A

It looks for antibodies to RBCs
Indirect antiglobulin test - looks for antibodies in the patient’s serum. This test is used to cross match blood for suitability for transfusion. Positive test means donor RBCs are INCOMPATIBLE
DAT (direct antiglobulin test) - done to detect antibody to patient’s own serum causing AIHA (autoimmune haemolytic anaemia)

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

Features of haemolytic anaemia

A

Anaemia - due to reduction in circulating RBCs
Splenomegaly - as the spleen becomes filled with destroyed RBCs
Jaundice - as bilirubin is released during destruction of RBCs

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

Congenital/Inherited haemolytic anaemias

A

RBC membrane abnormalities - hereditary elliptocytosis, hereditary spherocytosis
RBC enzyme deficiencies - G6PD deficiency, pyruvate kinase
RBC haemoglobin disorders - thalassaemias, sickle cell disease

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

Acquired causes of haemolytic anaemia

A

AIHA (autoimmune haemolytic anaemia)
Microangiopathic haemolytic anaemia (HUS, TTP, DIC)
Drugs, infections, toxins
Copper deficiency (Wilson’s disease)

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

Who is Hereditary spherocytosis common in?

A

Northern Europeans

- Autosomal dominant

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

Presentation of Hereditary spherocytosis?

A

Jaundice
Gall stones
Splenomegaly

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

Diagnosis of hereditary spherocytosis?

A

Look for positive family history
FBC
Reticulocyte count - immature RBCs and is raised due to rapid turnover of RBCs
Blood film - look for spherocytes (sphere RBCs)
EMA-binding

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

Treatment of hereditary spherocytosis?

A

Give folic acid regularly
Often need splenectomy
Removal of gallbladder

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

In whom is G6PD deficiency seen?

A

Mainly males - X-linked

Common in people from the Mediterranean (e.g. Turkish)

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

What are the triggers of G6PD deficiency?

A

Fava/broad beans
Infections
Medications
- need to avoid: Antimalarial, Aspirin (large doses), Chloramphenicol, Dapsone, Phenylhydrazine, Nalidixic acid, Nitrofurantoin and Vitamin K

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

Symptoms of G6PD deficiency?

A

Feeling unwell and lack energy
Become pale and yellow in colour (intermittent jaundice)
Have a backache
Passing dark urine (cola)

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

How is GP6D deficiency diagnosed?

A

Done using a G6PD assay

On a blood film - ‘Heinz’ bodies are seen (denatured haemoglobin)

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

What genes are present in sickle cell anaemia and in what populations?

A

Autosomal recessive disorder
- Carriers: HbAS
- Affected: HbSS
Prevalent in Africa

17
Q

What is vaso-occlusive crises sickle cell anaemia?

A

Vaso-occlusive crisis

  • The cells can ‘sickle’ which blocks capillaries causing ischaemia
  • Causes extreme pain (deep pain) and fever can result
  • Can be triggered by dehydration and infections
  • (Priapism - painful erection)
18
Q

How to manage vaso-occlusive crisis?

A

Give fluid (via IV if needed)
Abx if necessary
Analgesia - consider opiates
Keep warm

19
Q

Acute chest syndrome crisis and its management?

A

Syndrome that requires fever or respiratory symptoms with new infiltrates seen on x-rays - lungs can suddenly lose their ability to breathe in O2

Can be caused by infections or vast-occlusion
Emergency so needs - Abx/antivirals, blood transfusions and NIV or even intubation

20
Q

What splenic issues may arise in sickle cell anaemia?

A

Auto-infarction of spleen - increased risk of infection
Splenic sequestration
- Cells can block blood flow to spleen causing an acute painful splenomegaly
- Due to blood build up in spleen, it can reduce circulating volume -> leading to shock
- Treated with: blood transfusions and fluid resus.

21
Q

Stroke risk in sickle cell disease prevention?

A

Primary stroke prevention - done using a transcranial Doppler to assess Circle of Willis
- Give regular transfusions
Secondary stroke prevention - following a stroke start regular blood transfusions

22
Q

Treatment of sickle cell anaemia?

A

Avoid dehydration and other triggers of crises
Ensure vaccines are up to date (e.g. give regular Pneumovax - stops pneumococcus)
Abx prophylaxis - penicillin V
Hydroxyurea - e.g. hydroxycarbamide
- enables production of HbF (fetal haemoglobin - 15% helps prevent crises)
Immediate morphine - for agonising bone pain

23
Q

What is thalassaemia?

A

A complex group of autosomal recessive disorders that affect the haemoglobin chains

In thalassaemia, the red blood cells are more fragile and break down more easily

Microcytic anaemia

24
Q

What are the signs and symptoms of thalassaemia?

A 
Pallor
Jaundice
Gallstones
Splenomegaly
Poor growth and development
Bone deformities - pronounced forehead and deformed cheek bones
25
Q

What is management based upon for thalassaemia?

A

Long term blood transfusions and iron chelation (removal of excess iron)

Don’t start chelation too early – wait till Ferritin >1000ug/L to avoid neuro and skeletal toxicity

26
Q

What medication is used in treatment of thalassaemia?

A

First line treatment up to age of 6 - Desferal

  • SC injection up to 5x per week
  • Painful
  • Poor compliance
  • Potential neuro and skeletal toxicity

First line treatment >6 years - Exjade (desferasirox)

  • PO OD
  • No neuro/skeletal toxicity
  • Good compliance
27
Q

What is autoimmune haemolytic anaemia (AIHA) and the types?

A

Autoimmune haemolytic anaemia occurs when antibodies are created against the patient’s RBCs

There two basic types: warm (more common) and cold depending on the thermal range across which the antibody is active

  • Cold at occurs at less than 10C
  • Warm has POSTIVE DAT test
28
Q

What does the blood film show for warm AIHA?

A

IgG
Micro-spherocytes (red arrows) and polychromatic macrocytes (blue arrows)
Blood film is just like hereditary spherocytosis but Coomb’s test is positive in AIHA
Extravascular
Steroid responsive

29
Q

What does blood film show for cold AIHA?

A

IgM
Clumps of red cells agglutinated by the presence of cold agglutinins
Intravascular haemolysis can lead to haemoglobinuria
Treat by avoiding cold

30
Q

What are the underlying causes?

A

Warm AIHA - more common

  • Idiopathic
  • Secondary: Rheumatoid disease e.g. SLE(systemic lupus ertythematous), Lymphoma
  • Chronic Lymphatic Leukaemia Drugs: e.g. cephalosporins Ovarian Teratoma

Cold AIHA

  • Idiopathic
  • Secondary: 
EBV (Epstein Barr Virus) infection, Mycoplasma pneumonia, Ulcerative Colitis
31
Q

Management of AIHA?

A

Blood transfusions
Prednisolone (steroids) - 1mg/kg in acute scenario (OD)
- (BD will result in patient staying awake)
5mg OD Folic Acid
Rituximab (a monoclonal antibody against B cells)
Splenectomy

Anaemia (3 decks)

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