Anaemia Flashcards
anaemia definition
low level of Hb in the blood
<120 women Hb grams/litre
MCV <80
sex hormone-related to anaemia
less due to menstruation
<130 men Hb grams/lire
MCB <80
e.g. testosterone makes more hb
pregnancy second trimester and third expect <110 in hb (haemodilution)
3 categories of anaemia
microcytic anaemia
normocytic anaemia
macrocytic anaemia
microcytic anaemia
T – Thalassaemia A – Anaemia of chronic disease I – Iron deficiency anaemia L – Lead poisoning S – Sideroblastic anaemia
normocytic anaemia
3A’s
2H’s
A – Acute blood loss
A – Anaemia of Chronic Disease (limits the amount of iron that can enter the body due to a protein called hepsidin) (all cells in the body need iron so all cells need ferritin to lock away the iron) (hepsidin limits iron micoavailabilty from micro organism) (downregulation of RBC production via IL6) (less iron into less RBC so looks normal)
A – Aplastic Anaemia
H – Haemolytic Anaemia
H – Hypothyroidism
fresh blood if below the recto-sigmoid
macrocytic anaemia
FAT RBC
Folate deficiency*
Alcohol (macro but not anaemia) (typically associated with folate deficiency)
Thyroid (hypo) (thyroxine and erythropoeitn)
Reticulocytosis (usually from haemolytic anaemia)
B12 deficiency*
Cytotoxic drugs (azathioprine)
APLASTIC anaemia (associated with elevation of MCV)
Myeloma
Myelodysplasia (DNA opthay)
- megaloblastic anaemia (imapired DNA synthesis) so if deficient of b12 and folate they manifest in the cells which rapidly turn over (bone marrow)
- nervous tissue (die off) (neural tube defect) (peripheral neuropathy)
*reticulocytes are bigger than RBC so you churn over lots of haemolytic
symptoms of anaemia
Tiredness Shortness of breath Headaches Dizziness Palpitations Worsening of other conditions such as angina, heart failure or peripheral vascular disease
pica
hair loss
Pale skin
Conjunctival pallor
Tachycardia
Raised respiratory rate
Koilonychia is spoon shaped nails and can indicate iron deficiency
Angular chelitis can indicate iron deficiency
Atrophic glossitis is a smooth tongue due to atrophy of the papillae and can indicate iron deficiency
Brittle hair and nails can indicate iron deficiency
Jaundice occurs in haemolytic anaemia
Bone deformities occur in thalassaemia
Oedema, hypertension and excoriations on the skin can indicate chronic kidney disease
anaemia investigations
bloods
Haemoglobin Mean Cell Volume (MCV) B12 Folate Ferritin Blood film
anaemia investgiations
sepcial
Oesophago-gastroduodenoscopy (OGD) and colonoscopy to investigate for a gastrointestinal cause of unexplained iron deficiency anaemia. This is done on an urgent cancer referral for suspected gastrointestinal cancer.
Bone marrow biopsy may be required if the cause is unclear
iron deficiency anaemia pathophysiology
bone marrow requires iron to produce Hb.
- microcytic anaemia (MCV is low)
- ferritin <15
- insufficient dietary iron (hookworm and poor nutrition e.g. riced based diet)
- iron requirement increases (pregnancy)
- iron is lost (GI bleed e.g. colon cancer, oesophagitis, gastritis) (blood loss) (menstruating women, menorrhagia)
- inadequate iron absorption (coeliac, IBS)
where is iron usually absorbed?
duodenum and jejunum
required acid from the stomach to keep the iron in the soluable ferrous form
if acid drops, the ferrous is insoluable.
PPI therefore can impct iron absorption
coeliac disease / chron’s can cause inadequate iron absorption
tests for iron deficiency
iron travels around the body bound to transferrin = ferric ions.
TIBC is the total space on the transferrin molecule for iron to bind. If you have less transferrin, your TIBC will decrease
if you measure the amoutn of iron and then the TIBC you can calculate the proportion of transferrin molecules that are bound to iron
transferin saturatoin = sreum iron / TIBC
always low in iron deficiency and anaemia of chronic disease
iron deficiency= high TIBC
iron overload= low TIBC
what is ferritin?
ferritin is the form which iron takes when its stored in cells. (locks in iron- holds thousands of atoms of iron) most locates into macrophages / storage. released during inflammation / infection / cancer, extra ferritin is released. low ferritin is suggestive of iron deficiency, (<15) (15-30 low storage) (can raise in malignancy which can hide the low iron)
serum iron is not useful as it changes throughout the day
transferin saturation
transferin saturatoin = sreum iron / TIBC
check for iron overload (haemachormatosis if ferritin is high check transferritin saturatin)
good indication of total iron body. usualy around 30%
less iron in body = less transferrin is saturated
normal ranges for blood test investigating iron deficency anaemia
Blood Test
Serum Ferritin: 41 – 400 ug/L
Serum Iron: 12 – 30 μmol/L
Total Iron Binding Capacity: 45 – 80 μmol/L
Transferrin Saturation: 15 – 50%
high iron levels
iron overload
supplementation with iron
acute liver damaged (lots of iron stored in the liver)
