Haem / Onc Flashcards
give 3 causes of microcytic anaemia
TICS Thalassaemia Iron-deficiency Chronic disease (20% will be microcytic) Sideroblastic anaemia.
give 3 causes of normocytic anaemia
- bleeding
- anaemia of chronic disease (80% is normocytic)
- bone marrow failure; - renal failure (decreased erythropoietin)
- hypothyroidism
- haemolytic anaemia
- pregnancy
give 3 general symptoms of anaemia
classic = fatigue, dyspnoea, faintness
+ palpitations, headache, tinnitus, anorexia
give 3 general signs of anaemia
classic = conjunctival pallor
pallor, tachycardia
give a physiological cause of anaemia
pregnancy (normocytic)
give some causes of iron-deficiency anaemia
- inadequate intake: poor diet, poverty
- poor absorption: poor acid production, gastric surgery, coeliac
- excessive loss: GI bleeding, peptic ulcers (NSAID use), diverticulosis, neoplasm, menorrhagia
- increase requirement: infancy, pregnancy, hookworm
describe what is seen on a peripheral blood film in iron-deficiency anaemia
microcytic hypochromic RBCs, varying in size and shape (anisocytosis and poikilocytosis)
possible presenting features of iron deficiency anaemia?
koilonychias (spoon nails)
mouth changes - angular stomatitis, atrophic glossitis
fatigue, pallor, faintness, dyspnoea
pica (classic = ice craving)
In iron deficiency anaemia, what will happen to the iron, ferritin and total iron binding capacity (TIBC) (aka iron studies)?
iron and ferritin are decreased.
TIBC is increased.
transferrin saturation = low.
NB - ferritin is acute phase protein so may be raised in inflammation/infection/malignancy
how would you treat iron deficiency anaemia? how long would this treatment be given?
oral ferrous sulphate - given until anaemia resolved + further 3-6/12
consider transfusion if symptomatic at rest w/ dyspnoea and chest pain.
what are some side effects of ferrous sulphate?
nausea, abdominal discomfort, diarrhoea/constipation, black stools
what diagnostic tests would you perform if you suspected anaemia?
blood count and film (Hb, haematocrit, MCV, MCHC, peripheral blood smear).
iron studies, B12 etc.
tests for cause e.g. coeliac serology, endoscopy etc if IDA.
how would you treat anaemia of chronic disease?
treat underlying disease.
give Epo.
what is sideroblastic anaemia?
think of it as microcytic hypochromic anaemia that doesn’t respond to iron.
inherited or acquired disorder - body has enough iron but can’t incorporate it into Hb (ineffective erythopoeisis).
iron absorption is increased.
investigations for sideroblastic anaemia?
microcytic hypochromic anaemia.
blood film = dimorphic population of normal and hypochromic red blood cells.
iron studies: serum iron high, serum ferritin high, TIBC low.
marrow aspirate = presence of sideroblasts - “perinuclear ring of iron granules with Prussian Blue staining”
how would you treat sideroblastic anaemia?
mostly supportive.
iron chelation - desferrioxamine.
repeated RBC transfusions if needed.
avoid alcohol + vit C (they increase iron absorption).
if hereditary - consider Pyridoxine (vit B6).
give 3 causes of sideroblastic anaemia.
- inherited (XLSA - X-linked)
- myelodysplastic syndrome (MDS)
- myeloma
- PRV
- pyridoxine (B6) deficiency
- drugs (isoniazid)
- alcohol misuse
- lead toxicity.
what causes pernicious anaemia?
autoimmune atrophic gastritis - autoantibodies against parietal cells and intrinsic factor, so these are destroyed leading to achlorydia and B12 malabsorption.
associated with other AI disease - thyroid, vitiligo, DM.
risk of gastric cancer.
how does B12/folate deficiency lead to anaemia?
B12 and folate needed for DNA synthesis - developing red cells can’t divide, they are stuck as large immature cells (megaloblastic) which then become macrocytic RBCs
what signs characterise pernicious anaemia?
mild jaundice due to haemolysis - pallor + jaundice = “lemon tinged skin” is classic.
headache is hallmark of megaloblastic anaemia.
what specific tests would you perform if you suspected pernicious anaemia?
FBC, blood film etc and:
- intrinsic factor antibody
- antiparietal cell antibody (90% sensitive, but not specific as elevated in atrophic gastritis)
- Schilling test (radiolabelled B12)
give some causes of folate deficiency
poor diet.
increased demand - pregnancy or increased cell turnover.
malabsorption (coeliac)
drugs, alcohol, MTX (inhibits folic acid synth).
folate present in green veg, nuts, liver.
get macrocytic anaemia but NO neurological signs - B12 deficiency you also get peripheral neuropathy and neuropsych issues.
how would you investigate and treat folate-deficiency anaemia?
blood film shows macrocytic RBCs, hypersegmented neutrophils.
do other anaemia bloods.
oral folic acid (1-5mg) + B12 for 4 months min. treat cause.
if pancytopaenia present as well consider packed RBC transfusion.
give some acquired causes of haemolytic anaemia
Immune mediated:
- due to autoantibodies and direct antiglobulin +ve (Coombs’ positive), often part of another autoimmune condition (SLE, scleroderma etc).
Non-immune mediated:
- direct antiglobulin (Coombs) negative
- infection e.g. hep B and C, malaria
- microangiopathic haemolytic anaemia - HUS, TTP, DIC
- provides venous drainage for head, neck, upper limbs/thorax- extends from junction of R and L innominate veins to R atrium- surrounded by: sternum, trachea, R bronchus, aorta, pulmonary artery + perihilar + peritrachael lymph nodes- runs along R side of mediastinumwhen it's obstructed, collateral pathways form to provide alternative route for blood to return to R atrium
how do you determine when to stop abx in neutropenic sepsis?
outline management of spinal cord compression