HAEM - Micro and Macrocytic Anaemia Flashcards
Def anaemia
Decreased haemaglobin in blood such that = inadequate O2 delivery to the tissues
Hb value anaemia men
<135g/L
Hb value anaemia women
<115g/L
Sx anaemia (non-specific)
Fatigue
Weakness
Headaches
Sx anaemia (CV)
Intermittent claudication
Dyspnoea on exertion
Angina
Signs anaemia (4)
Pallor
TachyC
Systolic flow murmur
Cardiac failure
Specific sign IDA
Koilonychia
Specific sign haemolytic anaemia
Jaundice
Specific sign sickle cell anaemia
Leg ulcers
What drug should be given alongside blood transfusions and WHY
Furosemide
HF risk
Ways iron is stored
As intracellular ferritin + hemosiderin - macrophages, of spleen, liver, BM
Intracellular ferritin - hepatocytes
Myoglobin in Fe-containing enzymes
What 4 things should a low Hb be considered in relation to?
WBC count
Platelet count
Reticulocyte count
Blood film
Microcytic anaemia value
<80fL
Causes microcytic anaemia
Sideoblastic anaemia
Lead poisoning
Thalassaemia
IDA
Causes normocytic anaemia (8)
Acute blood loss Anaemia chronic disease Renal anaemia Haemolytic anaemia Marrow failure Pregnancy CT disease Diamorphic blood film
Macrocytic anaemia value
> 96fL
Causes macrocytic anaemia
B12 defic FOlate defic Alcohol XS Myelodysplastic syndrome Severe hypothyroidism
What is diamorphic blood film?
Combined macro/microcytic processes
Clinical examination findings IDA (5)
Koilonychia angular stomatitis brittle hair/nails atrophy of papillae of tongue Syndromes dysphagia/glossitis
What are the 4 Fe studies
Serum Fe
Serum ferritin
Total Fe binding capacity
Serum soluble transferrin receptors
What does IDA look llike on blood film
Microcytic, hypochromic (pale on blood film)
Poikilocytosis
Anisocytosis
What is the latent Fe deficiency period?
Where normal Hb is maintained despite Fe deficiency
What is the most common cause of IDA in the world?
Hookworm
What are the most common causes of IDA in the UK?
Blood loss
Menstruation
Other causes of IDA
Decreased absorption - coeliac/antacids/post gastrectomy
Increased demand - growth/pregnancy
Inadequate intake
Poikilocytosis
Shape variation
Anisocytosis
Size variation
Fe marker values IDA
Serum Fe = decreased
TIBC = increased
Serum ferretin = decreased
Soluble transferrin receptor = increased
Which is the most specific test for IDA
Soluble transferrin receptor
DDx IDA
Anaemia of chronic disease
Fe marker values anaemia of chronic disease
Serum Fe = decreased
TIBC = decreased
Serum ferritin = increased
STR = normal
What does serum ferretin represent in anaemia of chronic disease?
Increased stored iron (b.c is an acute phase reactant)
Mx IDA
Address underlying cause PO FeSO4 200mg t.d.s Increase dietary intake Monitor - blood parameters after 1 month Continue for 3 months after blood parameters return to norm
What can be done if pt is not tolerating Ferrous sulphate
Switch to ferrous gluconate
SE ferrous sulphate
Cramping Bloating N+V Constipation Black stools
Rules of 10’s
Max [Hb] in 1 week = 10g/L
If >10g/L decline in 1 week - blood is being lost
When transfusing - 1 bag will raise Hb [ ] by 10g/L
Who gets Plummer-Vinson syndrome
post-menopausal women
Mx Plummer-Vinson syndrome
Fe
Mechanical widening of oesophagus
Sx beta-thalassaemia minor
Usually asymp
What state can make minor beta thalassaemia worse?
Pregnancy
PS B-thalassaemia major
Severe anaemia
HSmegaly
FTT
+/- facial deformities
Blood film b-thalassaemia major
Hypochromic microcytic cells + target cells + nucleated RBC
Mx major b-thalassaemia
Lifelong blood transfusions
What is Bart’s hydrops
Deletion of all 4 alpha genes –> HbBarts (y4)
Outcome Bart’s hydrops
Death in utero
Deletion of 3 genes in alpha thalassaemia –>
Moderate microcytic anaemia + features haemolysis
Deletion of 2 genes in alpha thalassaemia –>
Asymp carrier with reduced MCV
Deletion of 1 gene in alpha thalassaemia –>
Clinically normal
Cause sideroblastic anaemia
Congenital
Or
Acquired in myelodysplastic syndrome
Approach to macrocytic anaemia
Blood film
LFT/TFT
Serum B12/folate levels
BM biopsy
Relevance of serum folate levels
reflects recent intake
Next Ix to do if B12 is low
Anti-parietal cell Ab
Anti-IF Ab
Schilling test
Schilling test
Distinguishes between pernicious anaemia and small bowel disease
Deoxyuridine suppression test
Differentiate B12/folate deficiency in vitro after BM biopsy
mechanism by which b12 and /or folate deficiecy lead to anaemia
B12 - coenzyme for conversion folate to activated folate
ac folate = req for DNA synthesis
DNA fails to stop erythrocyte development –> v large cells = trapped = destroyed in reticuloendothelial system
causes vit B12 definciency (3)
Chronic low uptake (vegan)
Impaired binding in stomach
Small bowel disease/terminal ileium disease
What 3 things can cause mild impairment Vit B12 absorption
Pancreatitis
Coeliac disease
Metformin use
What is pernicious anaemia
Autoimmune disease leading to severe B12 deficiency
What are the 2 types of antibodies that may contribute to pernicious anaemia?
Blocking autoantibodies
Binding autoantibodies
Blocking autoantibodies pernicious anaemia
Prevent IF-B12 binding
Binding autoatibodies pernicious anaemia
Prevent if binding to ileal receptors
Features pernicious anaemia
Lemon skin
Intramedullary haemolysis
High unconjugated bilirubin
What is subacute combined degeneration of the cord
Simultaneous posterior column (LMN) and CST (UMN) loss
What is subacute combined degeneration of the cord due to?
B12 deficiency
Triad subacute combined degeneration of the cord
Extensor plantars
Brisk knee jerk
Absent ankle jerks
PS subacute combined degeneration of the cord (6)
Peripheral neuropathy Extensor plantars Brisk knee jerk Absent ankle jerks Tone and power normal Gait may be ataxic
Where in the digestive system is folate absorped?
Jejunum
How long do the body’s reserves of folate last?
3 months
Causes folate deficiency
Poor nutritional intake
Malabsorption - Chrons
Anti-folate drugs
XS physiological - pregnancy, prematurity
XS pathological - XS eryhtrocyte prod, malig, Inflamm disease
E.g.s of drugs that cause folate deficiecy (3)
Methotrexate
Trimethroprim
Anti-convulsants
Tx folate deficiency
folic acid 5mg /day PO for 4 months
Always combine w/ B12 (unless Pt known to have norm B12 levels)
what condition can XS folate precipitate?
Subacute combined degeneration of cord
