Anaemia Flashcards
1
Q
Anaemia
How is anaemia classified (bloods)?
A
Hb:
< 12g/dL in females
<13.5g/dL in males
2
Q
Anaemia
What is the most common cause of anaemia?
A
iron deficiency anaemia
3
Q
Anaemia
List the types of microcytic anaemia.
(4)
A
- iron deficiency
- thalassemias
- sideroblastic
- anaemia of chronic disease
4
Q
Anaemia
Macrocytic anaemias can be megaloblastic and non-megaloblastic.
Name some causes of megaloblastic anaemia.
(2)
A
- Vit B12 deficiency
- folate deficiency
5
Q
Anaemia
Macrocytic anaemias can be megaloblastic and non-megaloblastic.
Name some causes of non-megaloblastic anaemia.
A
rare
- Chronic alcoholism
- Liver disease
- Hypothyroidism
- Drugs e.g. anti-retroviral for HIV or hydroxyurea
- Myelodysplastic syndrome
6
Q
Anaemia
List the causes of normocytic anaemia.
(4)
A
- Increased loss or breakdown of red blood cells (increased reticulocytes)
- Decreased production of red blood cells (normal or decreased reticulocytes)
- Increased plasma volume (normal or decreased reticulocytes)
- Coeliac disease
7
Q
Anaemia
What circumstances might cause increased a loss or breakdown of red blood cells (increased reticulocytes) causing anaemia?
(2)
A
Haemolysis
or
Haemorrhage
8
Q
Anaemia
What are some causes of haemolysis?
grouped into 2 sets
A
Acquired
- infections (malaria)
- autoimmune disorders
- physical damage (from an artificial heart valve)
- drugs
Hereditary
- G6PD deficiency (X – linked recessive and more common in African/Mediterranean backgrounds)
- sickle – cell anaemia
- hereditary spherocytosis
- paroxysmal nocturnal haemoglobinuria
9
Q
Anaemia
What circumstances might cause decreased production of red blood cells (normal or decreased reticulocytes) causing anaemia?
(3)
A
- CKD or EPO deficiency
- Bone marrow suppression* (due to infection/drugs/malignancy)*
- Anaemia of chronic disease
10
Q
Anaemia
What circumstance might cause **Increased plasma volume ** (normal or decreased reticulocytes) causing anaemia?
(1)
A
Pregnancy
11
Q
Anaemia
Why might coeliac disease cause normocytic anaemia?
A
mixed deficiencies of folate (macrocytic anaemia) and iron (microcytic anaemia) can occur cancelling each other out and causing normocytic anaemia.
12
Q
Anaemia
Name some symptoms of anaemia.
4
A
- fatigue / weakenss
- SOB
- pallor
- palpitations
13
Q
Anaemia
Name some Symptoms of vitamin B12 deficiency.
A
- Paraesthesia
- Ataxia/reduced sense of vibration/positive Romberg’s test due to degeneration of the posterior column
- Pale skin
- Petechiae
- Glossitis
- Angular cheilitis
- Cognitive impairment
+ Usual symptoms of anaemia
14
Q
Anaemia
Name some symptoms of folate deficiency.
A
- Headache
- Weight loss
+ Usual symptoms of anaemia
15
Q
Anaemia
Name some symptoms of haemolytic anaemia.
A
- Jaundice
- Splenomegaly may occur with hereditary spherocytosis or non – Hodgkin’s lymphoma
- Hereditary spherocytosis can cause gallstones – right upper quadrant pain
- Dark urine will be seen in intravascular haemolysis e.g. G6PD deficiency or paroxysmal nocturnal haemoglobinuria
+ Typical signs of anaemia
16
Q
Anaemia
What parameters of MCV classify:
- micro
- macro
- normo
anaemia
A
- Microcytic anaemia = MCV <80fL
- Macrocytic anaemia = MCV **>100fL **
- Normocytic anaemia = MCV 80-100fL
17
Q
Anaemia
How might iron studies come back for:
Iron deficiency anaemia
A
- low serum iron
- low ferritin
- increased total iron-binding capacity
- transferrin <16%
18
Q
How might iron studies come back for:
Thalassemia
A
normal
19
Q
How might iron studies come back for:
Sideroblastic anaemia
A
- high serum iron
- high ferritin
- low total iron-binding capacity
20
Q
How might iron studies come back for:
Anaemia of chronic disease
A
- low serum iron
- high ferritin
- low total iron-binding capacity
- transferrin 5-15%
21
Q
Anaemia
What might cause Vit B12 deficiency?
A
- vegan diet
- Crohn’s disease
- gastric bypass
- pernicious anaemia
22
Q
What might cause folate deficiency?
A
pregnancy or diet
23
Q
Anaemia
What might cause iron deficiency anaemia?
A
- Blood loss
- diet
- Poor iron absorption e.g. coeliac disease, IBD, H. Pylori, GI surgery or TMRPSS6 gene mutation
24
Q
Anaemia
How do pts with beta-thalassemia trait present?
A
usually asymptomatic with little anaemia, but marked microcytosis
25
# Anaemia
What is sideroblastic anaemia?
Why might be the cause of this happening? (3)
iron accumulation in red blood cell’s mitochondria prevents the ability to use iron to produce haemoglobin
- **Inherited** *(X – linked recessive, ALAS2 gene)*
- **Acquired** *e.g. alcoholism, myelodysplastic syndrome, copper deficiency, B6 deficiency*
- **Idiopathic**
26
# Anaemia
What chronic diseases might cause anaemia of chronic disease?
Autoimmune disease
Cancer
27
# Anaemia
What might reticulocyte count be like in normocytic anaemia?
**Hyperproliferative** (reticulocyte count >2%) due to haemmorhage/haemolysis and therefore increased erythropoeisis
**Hypoproliferative** (reticulocyte count <2%) due to disease of decreased erythropoeisis originally
28
# Anaemia
Why might creatinine be raised in a pt with normocytic anaemia?
CKD
29
# Anaemia
What investigation (beyond bloods) might you do for iron deficiency anaemia?
* Test for **H. Pylori** infection
* Consider faecal occult blood test and endoscopy or colonoscopy in patients with **suspected GI bleeding**
* **Coeliac serology** to rule out coeliac disease
30
# Anaemia
What investigation is required to diagnose sideroblastic anaemia?
What will a positive test show?
Bone marrow biopsy and staining of red blood cells
- ringed sideroblasts in mitochondria seen.
31
# Anaemia
What investigation (beyond iron studies) might you do for megaloblastic anaemia?
* Blood smear
* Test vitamin B12 and folate levels
* Plasma homocysteine
* Plasma or serum methylmalonic acid
* Test for anti–Intrinsic factor antibodies
* Endoscopy for patients with suspected Crohn’s disease
32
# Anaemia
How would a blood smear help is to differentiate between megaloblastic and non-megaloblastic anaemia?
Macrocytosis and hypersegmented neutrophils seen on a blood smear for **megaloblastic**
33
# Anaemia
How do **plasma homocysteine** and **plasma/serum methylmalonic** appear in B12 and folate deficiency?
**Plasma homocysteine**
- increased in B12 deficiency
- increased in folate deficiency
**Plasma/serum methylmalonic acid**
- increased in B12 deficiency
- normal in folate deficiency
34
# Anaemia
What investigation (beyond bloods) might you do for non-megaloblastic anaemia?
| Very complicated, just read thru this one
* **Imaging** to look for suspected haemorrhage.
* **Haemolysis**: increased LDH, decreased haptoglobin, increased bilirubin, raised reticulocytes. A peripheral smear will show abnormal red blood cells such as schistocytes, spherocytes, blister cells or tear cells depending on the cause.
* **Hereditary spherocytosis** (haemolytic anaemia) can cause gallstones which can be seen on x-ray.
* Coombs test used to test for or rule out **autoimmune haemolytic anaemia**, in which case it will be positive.
* Haemoglobin electrophoresis may be needed to diagnose **sickle cell disease**.
* **G6PD deficiency**: Peripheral blood smear will show Heinz bodies and bite cells. (Note that during an acute attack, G6PD levels will not be low).
* Flow cytometry is needed for **paroxysmal nocturnal haemoglobinuria** diagnosis: >1-3% of anchor-deficient granulocytes.
35
# Anaemia
How do we treat pts with iron deficiency anaemia? (prescribing)
Iron replacement
* **Oral**
* Consider **ascorbic acid** alongside iron supplementation if oral iron is not well tolerated.
* **IV** iron replacement can be used for patients not tolerating oral iron.
* A **blood transfusion** may also be required.
36
# Anaemia
In what form do pts take oral iron replacement? What is taken alongside it?
* ferrous sulphate
* ferrous gluconate
* ferrous fumarate
* ferric maltol
usually taken alongside vitamin C
37
# Anaemia
How do we treat pts with Vit B12 deficiency, *asymptomatic/mild deficiency*? (prescribing)
**vegan pts or over 65 years old with an inadequate diet**
- oral B12 supplementation
- if no response -> cyanocobalamin or hydroxocobalamin for life.
**pts with chronic GI condition/reasons** cyanocobalamin or hydroxocobalamin should be used.
38
# Anaemia
How do we treat pts with Vit B12 deficiency, *symptomatic*? (prescribing)
**mild/moderate symptoms **
- lifelong cyanocobalamin or hydroxocobalamin
**severe symptoms**
- parenteral cyanocobalamin or hydroxocobalamin for life is required.
- refer to specialist to a
*Some patients may also require a blood transfusion and folic acid supplementation also.*
39
# Anaemia
Who do we give folate supplementation to? (prescribing)
| (2)
* All pregnant women
* those at risk of deficiency from other conditions
40
# Anaemia
How do we treat pts with normocytic anaemia caused by chronic renal disease:? (prescribing)
Erythropoiesis stimulating agents
- **epoetin alfa** can be used
41
# Anaemia
How do we manage sickle cell disease? (prescribing / non-prescribing)
* Long term **hydroxycarbamide**
* Avoid cold weather, sudden changes in temperature, high altitude or dehydration to **prevent a sickle cell crisis**.
* **Regular blood transfusions with iron chelation therapy** may be required.
42
# Anaemia
How do we treat paroxysmal nocturnal haemoglobinuria? (prescribing)
* Eculizumab
* Blood transfusions
43
# Anaemia
How do we treat siderolastic anaemia?
* Treat underlying cause
* Vitamin B6 therapy
* **Desferrioxamine** subcutaneously or intramuscular used to remove excess iron
44
# Anaemia
How do we manage G6PD deficiency?
* **Avoid** broad beans or drugs that can cause an attack such as primaquine, aspirin, dapsone or sulphonamides.
* **Blood transfusions** and **folic acid supplementation**.
* **Splenectomy** may be required
45
# Anaemia
What should pt with G6PD deficiency avoid?
broad beans
drugs that can cause an attack:
- primaquine
- aspirin
- dapsone
- sulphonamides
46
# Anaemia
How would these values be in IDA?
____ Hb and haematocrit
____ MCV and ____ MCH
Peripheral blood smear showing ____ and ____
____ Reticulocyte count
____ Serum Iron
____ Total iron-binding capacity (TIBC)
____ Transferrin Saturation
____ Serum Ferritin
< Hb and haematocrit
< MCV and Total iron-binding capacity (TIBC)
< Transferrin Saturation
< Serum Ferritin
47
# Anaemia
Name some classical signs and symptoms of IDA
| 10
* Fatigue
* Headaches
* Exercise intolerance
* Weakness
* Pica
* Restless Leg Syndrome
* Exertional Dyspnoea
* Koilonychia
* Cheilosis/Angular Cheilitis
* Atrophic Glossitis
48
# Anaemia
Who is IDA most common in?
| 2
most common amongst women of childbearing age, children, and those living in middle or low-income countries
49
# Anaemia
IDA can stem from 3 groups of issues:
* Reduced iron intake
* Increased requirements of iron
* Iron loss
50
# Anaemia
Name 4 inherited types of haemolytic anaemias.
* Hereditary spherocytosis
* Glucose-6-phosphate deficiency
* Pyruvate kinase deficiency
* Haemoglobinopathies *(sickle cell anaemia and thalassaemia)*
51
# Anaemia
What are the 2 mechanisms of destruction of red blood cells in haemolytic anaemia?
intra (occurs within the circulation) and extravascular (a normal physiological process)
52
# Anaemia
What are red blood cell fragments on a blood film called?
Schistocytes
53
# Anaemia
When might you see schistocytes on a blood smear?
found in **microangiopathic haemolytic anaemias** *(e.g. disseminated intravascular coagulation, haemolytic uraemia syndrome, HELLP syndrome)* and traumatic processes *(e.g. mechanical prosthetic heart valve)*
54
# Anaemia
When might you see spherocytes on a blood smear?
found in hereditary spherocytosis and autoimmune haemolytic anaemias
55
# Anaemia
When might you see Blister or bite cells on a blood smear?
found in enzyme deficiencies
| (e.g. G6PD deficiency and pyruvate kinase deficiency)
56
# Anaemia
How might we manage autoimmune haemolytic anaemias?
corticosteroids to reduce AB porduction
57
# Anaemia
What might blood count and LFTs show in haemolytic anaemia?
* increased MCHC
* raised serum bilirubin
* raised LDH
58
# Anaemia
What might urinalysis show in haemolytic anaemia?
**haemoglobinuria**
*or haemosiderinuria in intravascular haemolysis*
59
# Anaemia
Which test detects the presence of antibodies bound to the red blood cell surface in vivo?
What diagnosis is this test helpful for?
Coombs test
- helpful in the diagnosis of** autoimmune haemolytic anaemia**, **haemolytic disease of the newborn** and **ABO transfusion reactions**.
60
# Anaemia
Sideroblastic anaemia is anaemia due to defective ____ synthesis. So if If ____ is deficient, iron stays trapped in mitochondria.
protoporphyrin
61
# Anaemia
Sideroblastic anaemia can be congenital (genetic) or acquired. The most common genetic defect is an X-linked defect in the ____ gene.
ALA synthase
62
# Anaemia
Acquired causes include **myelodysplastic syndromes** or **reversible acquired causes**.
Name some reversible acquired causes.
| 4
* **Alcohol** is the most common – mitochondrial poison
* **Lead poisoning** – inhibits ALAD and Ferrochelatase
* **Vitamin B6 deficiency** – needed cofactor for ALAS. This is most commonly seen as a side effect of isoniazid treatment for tuberculosis but can also be a side effect of linezolid therapy. This is reversible with Vitamin B6 (pyridoxine) administration.
* **Copper deficiency**
63
# Anaemia
Which stain can we use to visualise **ringed sideroblasts** in bone marrow in sideroblastic anaemiar?
prussian blue
64
# Anaemia
What may be seen in sideroblastic anaemia on a peripheral blood smear?
* **basophilic stippling** of RBCs
* **Pappenheimer bodies** (basophilic granules
* microcytic and hypochromic RBCs
65
# Anaemia
Lab findings of sideroblastic anaemia:
- ferritin
- TIBC
- serum iron
- % saturation
| tibc - total iron binding capacity
* increased ferritin
* normal/decreased TIBC
* increased serum iron
* increased % saturation (iron-overloaded state).
66
# Anaemia
Acute management of sideroblastic anaemia (congenital)
| 1st and 2nd line
**1st line**: A trial of pyridoxine (50 to 200 mg/day) +/- folic acid
**2nd line**: Second-line therapy involves packed red blood cell transfusions + iron chelation therapy
## Footnote
Erythropoietin and granulocyte colony-stimulating factor may be trialled in myelodysplasia-associated refractory anaemia with ringed sideroblasts.
67
# Anaemia
Acute management of sideroblastic anaemia (acquired, iatrogenic, drugs)
withdrawing the drug and administering pyridoxine
68
# Anaemia
Management for sideroblastic anaemia (chronic)
* **Periodic phlebotomy** if iron overloaded.
* **Bone marrow transplant** if the patient is young and anaemia is refractory to pyridoxine with iron overload and transfusion-dependence.
