Anaemia Flashcards
Hb levels for anaemia (males and females)
males (<135g/L)
females (<115g/L)
severe = <80g/L
Types of anaemia
microcytic (small MCV)
normacytic
macrocytic (large MCV)
symptoms of anaemia
fatigue
dyspnoea
faintness
palpitations
headache
tinitus/anorexia
signs of anaemia
pallor
severe (<80g/L) => hyperdynamic circulation => HF
- tachycardia
- ejection systolic mumur
causes of microcytic anaemia
Fe deficiency
Anaemia of chronic disease (cytokine driven inhibition of RBC production)
Sideroblastic anaemia (ineffective RBC production => iron loading in bone marrow)
Sickle cell
Thalassemia
causes of iron deficiency anaemia
blood loss (GI bleeding)
increased usage (pregnancy/lactation)
reduced intake (vegan/vegetarian)
reduced absorption (bariatric surgery, coeliac disease)
causes of GI bleeding => anaemia
Meckels diverticulum (older child)
menorrhagia (women <50)
colorectal cancer/ polyps (>50)
peptic ulcer disease/ gastritis (chronic NSAID use)
hookworm (developing countries)
signs of iron deficiency anaemia
angular cheliosis - blistering around mouth
koilonychia - spoon nails
atrophic glossitis - smooth tongue
brittle hair + nails
post-cricoid webs (Plummer- Vinson syndrome)
why are blood transfusions better for patients with anaemia and sepsis
iron won’t absorb well and can worsen sepsis so give transfusions
causes of anaemia of chronic disease
chronic infection (TB, osteomyelitis)
vasculitis
RA
malignancy
why is ferritin (store of iron) high in anaemic of chronic disease
stored in macrophages so invading bacteria can’t use it
causes of sideroblastic anaemia
myelodysplastic disorders
chemotherapy/ irradiation
alcohol excess
anti-TB
myeloproliferative disorders
causes of normacytic anaemia
blood loss
haemolytic anaemia (destruction of RBCs)
bone marrow failure
renal failure
primary myelofibrosis (BM cancer)
types of haemolytic anaemia
congenital
- GP6D deficiency
- hereditary spherocytosis
acquired
- autoimmune
- microangiopathic haemolytic anaemia (MAHA)
Causes of megaloblastic macrocytic anaemia
B12 deficincy
folate deficiency
cytotoxic drugs
Causes of non-megaloblastic anaemia
alcohol
reticulocytosis
liver disease
hyperthyroidism
pregnancy
how to differentiate between autoimmune and MAHA
autoimmune is direct antiglobulin test (DAT)/ COOMBs positive
How does COOMBs test work
detects antibodies stuck to surface of RBCs
- direct/indirect test
Types of MAHA
Haemolytic uraemic syndrome (HUS)
Thrombotic thrombocytopenic purpura (HUS + CNS signs/ fever)
Disseminated intravascular coagulation (DIC)
Symptoms of HUS
AKI
Thrombocytopenia (XS bleeding)
jaundice
which type of MAHA will a kid with E.coli infection get?
HUS
what is DIC
depletion of clotting factors due to overactivation of clotting cascade from infection/cancer
Types of DIC
acute - more bleeding (petechiae, purpura, ecchymoses)
chronic - slower more clotting (DVT/ arterial thrombosis)
How to diagnose DIC
FBC - low platelets
clotting profile - low fibrinogen, high fibrin degradation products
blood film - schistocytes
How does renal failure cause anaemia
reduced EPO secretion so bone marrow makes less RBCs
Causes of megaloblastic macrocytic anaemia
B12 deficiency
folate deficiency
antifolates
reticulocytosis
myelodysplastic syndromes
types of antifolate drugs
methotrexate
trimethoprim
what is myelodysplastic syndrome
group of cancers where immature blood cells in bone marrow don’t mature
initial investigations for anaemia
FBC (low RBC, low Hb, MCV)
U&Es (low EPO)
LFTs (liver problems/ alcoholics high GGT)
TFTs (hypothyrodism)
iron levels
B12/folate levels
clotting profile
investigations for iron deficiency anaemia
blood tests (iron studies)
if no obvious cause
- OGD +/- colonoscopy
- urine dip (loss of Hb in urine)
- anti-TTG (coeliac disease)
Special investigations for anaemia
blood film
- microcytic, hypochromic => iron deficiency
- megaloblasts => megalobasltic macrocytic anaemia
- schistocytes => DIC
How to diagnose sideroblastic anaemia
ring sideroblasts in the bone marrow on blood film (iron deposits around mitochondria like a ring)
management of anaemia
treat cause
oral ferrous sulphate
B12/folate supplements
SEVERE/SEPSIS => blood transfusions
bone marrow/stem cell transplants
treatment of iron deficiency anaemia
TREAT CAUSE
1. oral iron
2. severe anaemia => IV iron
treatment for sideroblastic anaemia
remove cause
give pyridoxine (vitamin B6 promotes RBC production)
