Anaemia in general medicine Flashcards
1
Q
What is the definition of anaemia
A
LOW HAEMOGLOBIN (Hb) —-<135g/L IN MEN AND <115g/L IN FEMALES
2
Q
What is anaemia due to
A
- low red cell mass
- increased plasma volume due to dilution
- reduced production
- increased loss
3
Q
What are the symptoms of anaemia
A
- FATIGUE
- DYSPNOEA
- FAINTNESS
- PALPITATIONS
- HEADACHES
- TINNITUS
- ANOREXIA
- ANGINA (IN PRE-EXISTING CORONARY ARTERY DISEASE)
4
Q
What are the signs of anaemia
A
Can be absent
- pallor
- hyper dynamic circulation - tachycardia, flow murmurs (ejection), cardiac enlargement
- retinal haemorrhages
- heart failure
5
Q
What is the normal mean cell volume (MCV)
A
76—96 FEMTOLITRES (10 TO THE POWER OF 15==1 LITRE)
6
Q
name the 3 causes of anaemia with low MCV
A
- iron deficiency anaemia
- thalassaemia
- sideroblastic anaemia
7
Q
What can cause normocytic anaemia
A
- acute blood loss
- anaemia of chronic disease
- bone marrow failure
- renal failure
- hypothyroidism
- haemolytic
- pregnancy
- mixed deficiency
8
Q
What causes macrocytic anaemia
A
- B12 or folate deficiency
- alcohol abuse
- liver disease
- reitculocytosis
- cytotoxic
- meylodysplastic syndormes
- marrow infiltration
- hypothyroidism
- anti-folate drugs
9
Q
what type of MCV can haemolytic anaemia be
A
- may be normocytic
- may be macrocytic as there are many young RBC in circulation
10
Q
What should you look for in haemolytic anaemia
A
- jaundice
- reticulocytes
- low haptoglobulin
- high LDH
- high urobilinogen
11
Q
What can cause iron deficiency anaemia
A
- blood loss (GI bleeding and menorrhagia)
- poor diet
- malabsorption
- GI parasites such as hookworm
12
Q
what causes koilonychia
A
iron deficiency anaemia
13
Q
What causes atrophic glossitis
A
- iron deficiency anaemia
14
Q
What causes angular cheilosis
A
- iron deficiency anaemia
15
Q
what causes post-cricoid web (Plummer Vinson Syndrome)
A
- iron deficiency anaemia
16
Q
name a GI parasite that can cause iron deficiency anaemia
A
- Tapeworm
17
Q
What would the blood test should you for iron deficiency anaemia
A
- LOW MCV
- LOW MCH
- LOW MCHC
- low SE ferritin
- low SE iron
18
Q
what does a blood film look like in iron deficiency anaemia
A
- Microcytic
- hypo chromic anaemia
- anisocytosis
- poikilocytosis
19
Q
What are the other tests that you can do for iron deficiency anaemia
A
- coeliac screen
- gastroscopy and colonoscopy
20
Q
what is the difference between ansiocytosis and polkilocytosis
A
- Anisocytosis - variation in RBC size
- Polkilocytosis = variation in shape
21
Q
What causes anaemia of chronic disease
A
- any chronic condition such as infection, vasculitis, autoimmune, malignancy and renal failure
22
Q
What does sideroblastic anaemia look like
A
- Low MCV
- unresponsive to iron
- ineffective erythropoiesis
- increased iron absorption
- iron loading in the marrow, endocrine, liver and heart
23
Q
What is sideroblastic anaemia
A
Sideroblastic anaemia is a disorder where the body produces enough iron but is unable to put it into the haemoglobin
24
Q
what can cause sideroblastic anaemia
A
Congenital
Acquired
- myelodysplastic/myeloproliferative diseases
- chemotherapy
- anti-TB drugs
- irradiation
- alcohol
- lead excess
25
what is the treatment of sideroblastic anaemia
- remove cause
| - +/- pyridoxine
26
macrocytosis can ...
MACROCYTOSIS CAN OCCUR WITHOUT ANAEMIA (EG ALCOHOL EXCESS)
27
What is a megaloblast
- cell in which nuclear maturation is delayed compared with the cytoplasm
28
What can cause megaloblastic anaemia
- B12 and folate deficiency
| - cytotoxic drugs
29
What can cause non megaloblastic anaemia
- alcohol excess
- reticulocytosis
- liver disease
- hypothyroidism
- pregnancy
30
What are the two types of macrocytic anaemia
- megaloblastic anaemia
| - non-megaloblastic anaemia
31
what are other causes of macrocytic anaemia
- myelodysplasia
- myeloma
- myeloproliferative disorders
- aplastic anaemia
32
what could you find in a bone marrow biopsy
- Megaloblastic marrow
- normoblastic marrow - liver disease and hypothyroid
- abnormal erythropoiesis (sideroblastic anaemia, leukaemia, aplasia)
- increased erythropoiesis (haemolysis)
33
What causes folate deficiency
- poor diet
- increased demand (pregnancy, increased cell turnover such as haemolysis)
- malabsorption
- alcohol
- drugs - phenytoin and methotrexate
34
How do you treat folate deficiency
- treat underlying cause
| - can give oral folic acid but make sure not B12 deficiency as this can cause subacute combined degeneration of the cord
35
Why do you take folate in pregnancy
- prevent spina bifida and anaemia
36
What can cause B12 deficiency
- diet
- malabsorption - B12 binds intrinsic factor in the stomach, this enables absorption in the terminal ileum
- congenial metabolic errors
37
what are the clinical features of B12 deficiency
- Pallor
- slightly jaundice (haemolysis)
- glossitis
- angular cheilosis
38
what are the clinical features of a B12 deficiency
- Neuropsychiatric - depression and psychosis
| - Neurological - paraesthesia, peripheral neuropathy
39
What are the two types of haemolytic anaemia
- Intravascular (within circulation)
| - extravascular (in reticuloendothelial system e.g. macrophages of liver, spleen and bone marrow)
40
When should you suspect haemolysis
- anaemia with normal or high MCV
- high bilirubin (unconjugated, pre-heaptic jaundice)
- high urinary urobilinogen (no urinary conjugated bilirubin)
- high serum LDH (released from red cells)
- high reticulocytes
- parasites on thick and thin films
- splenomegaly (in extravascular)
- intravascular - high free plasma haemoglobin, methaemalbuminaemia, haemoglobinuria, haemosiderinuria, reduced haptoglobin
- family history, race, drugs, previous episodes, travel
41
what does the blood film look like in haemolytic anaemia
- HYPOCHROMIC MICROCYTIC ANAEMIA (THALASSAEMIA)
- SICKLE CELLS
- SCHISTOCYTES (MICROANGIOPATHIC HAMEOLYTIC ANAEMIA)
- ABNORMAL CELLS (BLOOD MALIGNANCY)
- SPHEROCYTES (HEREDITARY, OR AUTOIMMUNE HA)
- ELLIPTOCYTES (HEREDITARY)
- HEINZ BODIES (GLUCOSE-6-PHOSPHATE DEHYDROGENASE—G6PD DEFICIENCY)
42
what tests should you do if you diagnosis of haemolytic anaemia is still in doubt
- osmotic fragility tests (membrane abnormalities)
- HGB electrophoresis (haemoglobinopathies)
- diet antiglobulin test (DAT) - Coombs - to idnetify red cells coated with antibody or complement (immune cause)
- enzyme assays
43
List the Coombs positive causes of haemolytic anaemia
- drugs
- autoimmune
- paroxysmal cold haemoglobinuria (viruses/syphilis)
- isoimmune (active transfusion reaction)
44
List the Coombs negative causes of haemolytic anaemia
- autoimmune hepatitis
- hep B and C
- post vaccination
- drugs
45
name other causes of haemolytic anaemia
microangiopathic haemolytic anaemia
- mechanical damage - eclampsia, prosthetic heart valves
Infection
- malaria
Paroxysmal nocturnal haemoglobinuria
- acquired stem cell disorder
- haemolysis
- marrow failure
- thrombophilia
46
What are hereditary causes of haemolytic anaemia
- G6PD deficnecy - drugs such as aspirin, sulphonamides, fava beans(broad beans)
- pyruvate kinase deficiency (causes reduced RBC survival, autosomal recessive)
- Membrane defects - hereditary spherocytosis/ elliptocytosis/ ovalocytosis
- Haemoglobinopathies - sickle cell and thalassamia
