Anaemia Flashcards
what is the definition of anaemia
low level of Hb in blood
what does MCV, MCH mean
mean corpuscular volume, indicates SIZE of RBC,
MCH = ave amount of Hb in each RBC
what is ferritin and folate and b12?
ferritin - intracellular protein that stores iron
folate - many forms of vitamin b9, including folic acid
b12 and folate work to make erythrocytes. makes up Hb
what are the general symptoms of anaemia
tiredness SOB headaches dizziness palpitations worsening of other conditions such as angina
generic signs of anaemia
pale skin
conjuctival pallor
tachycardia
raised resp rate
other specific signs of anaemia
koilonychia
angular chelitis
smooth tongue
jaundice - haemolytic
what lab tests can you do for anaemia
haematocrit= what % of blood is taken up by red cells
normal - 40%
Hb concentration
MCV - macrocytic or microcytic
reticulocyte count: low = cause of anaemia is due to reduced production
high = being made ok but destroyed prematurely
red cell morphology: hypochromic, spherocytic etc
what further investigations should you do for anaemia?
oesphago-gastroduodenoscopy and colonoscopy for GI bleed
bone marrow biopsy
what are the microcytic anaemias, and what are the features?
low MCV, low MCH
causes:
TAILS
thalassameias anaemia of chronic disease iron deficiency anaemia lead poisoning sideroblastic anaemia
what is IDA
inadequate iron containing foods in diet, or malabsorption, or blood loss
causes:
- physiological eg menarche, pregnancy
- neonatal: prematurity, LBW
- diet
- GIT: bleeding/NSAID’s/cancers
how do you diagnose IDA
low hb, low MCV, low MCH
specific symptoms to IDA
headache, esp with activity craving for non-food items smooth tongue brittle nails or hair loss koilonychia
how do you manage IDA
100-200mg elemental iron dialy eg
ferrous fumarate 210mg 2-3 times a day: raises Hb by 0.1 a day
treat till it is normal then 3 months after and maybe maintenance dose
what are side effects and contraindications of IDA
gi: nausea, black stools
may change to ferrous sulfate
- thyroxine tablets and antibiotics: take few hours apart
take with orange juice or on an amepty stomach
what is thalassaemia
absence of alpha globin or beta globin chains which are used for erythropoesis to form hb
what is beta thalassaemia
beta thalassaemia minor: 1 abnormal, and has raised HbA2 = mild microcytic
BT major has 2 abnormal genes = only HbF
what is alpha thalassaemia
4 genes: 1 deletd = clinically silent 2- AT trait 3- haemoglobin H disease 4 - bart's hydrops fetalis
what is the pathophys of thalassaemia
RBCs are more fragile and break down more easily
- spleen acts as a sieve to filter the blood and remove older blood cells but in thalassaemia spleen collects all the destroyed RBCs = splenomegaly
-bone marrow expands to produce extra RBCs to compensate for ammonia = susceptibility to fractures and bony features
what are the signs and symptoms of thalassaemia
low MCV fatigue pallor jaundice gallstones splenomegaly poor growth and development
how do you diagnose thalassaemia
FBC to show microcytic
Hb electrophoresis = globin abnormalities
DNA testing for genetic components
what is iron overload and what are the symptoms? (same symptoms as haemochromatosis)
result of faulty creation of RBCs, recurrent transfusions and increased absorption of iron in response to anaemia
fatigue, liver cirrhosis, infertility, heart failure, arthritis, diabetes and osteoporosis and joint pain
how do you manage thalassaemia?
long term blood transfusions, iron chelation (removal of iron excess by increasing excretion in urine or faeces)
- desferrioxamine, deferipone, deferasirox infusion over 8-12 hours, 5 nights per week
deferasirox is the first line for treatment > age 6
what are the side effects of DFP, DFX
painful, local inflammation, poor compliance, potential neuro and skeletal toxicity
what is macrocytic anaemia
high MCV - large RBCs
megaloblastic or normoblastic
megaloblastic = impaired DNA synthesis, preventing cell from dividing normally
rather than dividing = grows into larger or abnormal cell and is caused by b12 or folate def
pathophys of vitamin b12 deficiency
haptocorrin etc LOOK AT NOTES
what causes acquired b12 deficiency
nutritional - vegan, poor diet, pregnancy malabsorption: -gastric: surgery, pernicious anaemia -intestine -crohn's, coeliac etc
what is acquired folate deficiency syndrome
nutritional - poor diet, goat's milk intestinal - coeliac, jejunal resection excessive requirement eg pregnancy increased turnover like chronic haemolysis excess loss like dialysis
how do you manage folate deficiency anaemia
folic acid 5mg daily for 4 months
- for undiagnosed anaemia: never give folic acid alone, give with vit b12 concurrently
what are the signs and symptoms of b12 or folate deficiency
insidious onset mild jaundice and anaemia glossitis angular chelitis neuropathy
how do you treat vit b12 deficiency
hydroxocobalamin: every couple of days until stores replenished then every 2-3 months
cyanacocabalamin
other than megaloblastic anaemia, what are the other causes of macrocytosis?
- alcohol
- pregnancy
- drugs like chemotherapy (anti-folates etc)
- liver disease
- reticuloycytosis
- hypothyroidism
what is normocytic anaemia and what causes it?
normochromic and normal MCV but low Hb. central pallor <33%
3 A’s 2 H’s
-acute blood loss (bc blood cells left are normal but hb conc takes time to lower so may not be immediate)
- anaemia of chronic disease
-aplastic anaemia
h-haemolytic
h-hypothyroidism
hepcidin and ferroportin pathophysiology
??? notes
what is haemolytic anaemia and what are the different types?
anaemia due to destruction, rather than underproduction, of RBC
- hereditary spherocytosis
- elliptocytosis
- stomatocytosis
- G6PD and PK deficiency
- auto-immune haemolysis (Acquired)
how do you diagnose the haemolytic anaemias?
blood films
bilirubin
specific: coomb’s test, ema-bonding, G6PD level, Hb identification
what is spherocytosis
autosomal dominannt inherited abnormalities of red cell membrane proteins
= RBCs are sphere and fragile and broken down when passing through the spleen
what are the symptoms and signs of hereditary. spherocytosis and how do you treat it
jaundice
chronic haemolysis
gall stones
- give folic acid regularly
- may need splenectomy
how do you diagnose HS?
- family history
- reticulocyte count
- MCHC raised on blood film
if all that negative, use EMA-binding: binds to eryhtrocyte membrane proteins and if they have it the fluorescence is weaker cos missing proteins
what is G6PD?
x linked recessive disease, usually healthy between attacks. often FH of jaundice
- sudden onset of feeling unwell, lack of energy, jaundice, back ache, dark coloured urine
what is PK defieciency
autosomal recissive
-protruding spikes on RBCs
-chronic haemolysis
may need splenectomy
what is AIHA
auto-immune haemolysis
- warm and cold (what temp the antibody is active)
- need a blood fillm and a positive DAT or coomb’s
what causes AIHA
warm: idiopathic, or rheumatoid disease, CLL
cold: idiopathic, or EBV, ulcerative colitis
how do you manage AIHA
steroids: prednisolone
dont transfuse patients unless severely visibly unwell
what is SCA
beta globin variant, co-dominant
carriers HbAs normal, usually HbSS = patient has no normal Hb
what is a sickle cell crisis, how are the different types managed?
for example, painful crisis: blood supply to bone is blocked and hence bone infarction and painful
- NSAID’s at home or ICU opiates if severe
chest crises: sickling in alveoli
abdomen: sickling in ometum
- blood supply to brain gets cut off = stroke, so preventions like reg blood transfusions
what is the pathophys of SCA
most RBCs are disc shaped, and agglomerate with platelets and neutrophils to form clots that block off RBCs to rest of the body
- scd does not affect fetuses because the fetal hb have gamma chains not beta
how do you manage long term SCA
- penicillin and folic acid
- pneumovax to maintain immunity to pneumonia
- hydroxyurea (demethylating and switching ON their fetal Hb gene)
- stem cell transplant
