Anaemia Flashcards
Main signs of anaemia (5)
Skin and mucosal pallor
Pale conjunctiva
Fatigue
RR and HR increased
4 causes of microcytic anaemia
Sickle cell
Anaemia of chronic disease (but can be normocytic often too)
Thalassaemias
IDA
What does anisopoikilocytosis mean
Anisocytosis - unequal size
PoiKILOcytosis - unequal shape
What disease are pencil cells seen in
IDA
What is seen on the blood film of IDA (5)
Anisocytosis Poikilocytosis Pencil cells Hypochromic Microcytic cells
Three main ways you can get IDA
Reduced uptake
Increased loss
Increased requirement
What can cause reduced uptake IDA (4)
Malnutrition
Coeliac
IBD
Achlorhydria
What can cause increased loss IDA (4)
GI Malignancy
Peptic ulcer
IBD
Menstruation
What can cause increased requirement IDA (2)
Pregnancy
Breastfeeding
What is the triad for colon cancer
Unexplained IDA
PR bleeding
Weight loss
Which is increased in Anaemia of Chronic Disease?
Intrinsic factor Hepcidin TIBC Transferrin Ferroportin
Hepcidin
Changes to level of ferritin and TIBC in IDA?
Ferritin - down
TIBC - up
Changes to level of ferritin and TIBC in ACD?
Ferritin - up
TIBC - down
What causes anaemia of chronic disease
Increased hepcidin which reduces iron uptake, storage and release
Why does ferritin increase in ACD
It is an acute phase protein and so increases in infections
The chipmunk facies/skull abnormalities seen in thalassaemia are due to what
Extramedullary haematopoiesis
What are the 7 different types of thalassaemia
Alpha defect: Alpha+ Alpha° Hb H Hb Barts
Beta defect:
Beta minor
Beta intermedia
Beta major
Which type of thalassaemia is rarer - alpha or beta
Alpha
Which chromosome is affected to cause alpha thalassaemia
Chr 16
Which chromosome is affected to cause beta thalassaemia
11
Which thalassaemia does a defect in chromosome 16 cause
Alpha
Which thalassaemia does a defect in chromosome 11 cause
Beta
Describe the alpha thalassaemias and their severities
Alpha+ and Alpha° cause very mild anaemias (where you lack 1 or 2 alpha genes)
Hb H causes a significant anaemia (where you lack 3 alpha genes)
Hb Barts causes death in utero (no alpha genes)
Describe the beta thalassaemias and their severities
Beta minor often presents with a mild anaemia but a disproportionately low MCV
Beta intermedia is a variant condition – be aware it exists nothing more
Beta major – severe anaemia presenting in the first few months of life
Ix for thalassaemias
Microcytic anaemia
Normal Iron studies
When does alpha thalassaemia present
From birth
When does beta thalassaemia present
From early infancy
What is seen on the blood film of a sickle cell patient (2)
Howell-Jolly bodies
Sickled cells
Mx of an acute painful sickle cell crisis (4)
Saturate (supportive Oxygen)
Antibiotics (if needed)
Pain relief
Cannula (IV fluids)
Mx of a stroke with sickle cell disease
Exchange Blood Transfusion
Mx of a sequestration crisis with sickle cell disease
Splenectomy
Mx of a chronic cholecystitis with sickle cell disease
Cholecystectomy
How to diagnose SCA (2)
Hb electrophoresis + Blood film
Medical Mx of SCA
Vaccinations
Hydroxyurea
Prophylactic ABx
How does hydroxyurea work in SCA
Hydroxyurea increases production of HbF (which does not contain the defective beta globin S chain) which inadvertently reduces the total level of sickle-able cells.
Surgical Mx of SCA
Bone Marrow Transplant (curative)
What causes megaloblastic anaemia
Folate or B12 deficiency
What is seen in the blood film of megaloblastic anaemia
Hypersegmented neutrophils and macrocytic cells
Causes of vitamin B12 related megaloblastic anaemia (5)
Alcohol IBD/Coeliac Bariatric surgery Malnutrition Pernicious anaemia
Causes of folate related megaloblastic anaemia (5)
Alcohol
IBD/coeliac
Anti-folate drugs
Pregnancy
S/s of B12 deficiency (4)
Glove & stocking parasthesiae
Hyporeflexia
Romberg’s +ve
Subacute combined degeneration of the cord
Does B12 deficiency cause hypo or hyperreflexia
Hyporeflexia
In the subacute combined degeneration of the cord what does lateral corticospinal tract lesion result in:
Myopathy
In the subacute combined degeneration of the cord what does dorsal column tract lesion result in:
pressure, vibration and touch sense diminished
How long do your B12 reserves last for
3-4 years
Average onset of pernicious anaemia?
60 years old
RF for pernicious anaemia
AI PMHx
Which auto-antibodies are involved in pernicious anaemia (2)
Anti-Parietal cells
Anti-Intrinsic factor
Diagnostic criteria of pernicious anaemia (4)
Macrocytosis
Megaloblastic film
Neuro signs as seen in B12 deficiency anaemia
Low B12
Diagnostic criteria of folate deficiency (3)
Macrocytosis
Megaloblastic film
Low Folate
How long do our folate reserves last for
Around 6 months
Non-megaloblastic causes of macrocytic anaemia
Alcoholics May Have Liver Failure
Alcohol
Myelodysplasia
Hypothyroidism
Liver disease
Features of haemolytic anaemia (3)
Scleral icterus
Pallor
Pale conjuctiva
Bloods tests for haemolytic anaemia (4)
Hb low
Haptoglobin low
Unconjugated bilirubin raised
LDH raised
What are hereditary haemolytic anaemias and what are they a defect in (4)
Membrane - hereditary spherocytosis
Enzymes - G6PD deficiency
Haemoglobin - SC and thalassaemia
What is the direct anti globulin test also known as
Coombs test
What is the Coombs test also known as
Direct antiglobulin test
What does the Coombs test test for
Presence of antibody on the red cell surface - e.g. in AI haemolytic anaemia
What should be avoided if you have G6PD deficiency and why (2)
Beans and antimalarials - quinines due to oxidative stress
What is seen on blood film in G6PD deficiency anaemia (2)
Heinz bodies and Bite cells
What is the inheritance pattern of G6PD deficiency
X linked recessive
What is the inheritance pattern hereditary spherocytosis
Autosomal dominant
Diagnostic criteria for hereditary spherocytosis
Osmotic fragility test and Coombs’ test negative
Complications of hereditary spherocytosis
Aplastic crisis
What can trigger aplastic crisis in hereditary spherocytosis
Parvovirus B19
What is the ‘triad’ seen in HUS
Haemolysis
Urinary problems
Shits
What are the GI features of HUS (2)
Abdominal Pain
Bloody Diarrhoea
What population gets HUS
Early childhood - usually through infection of EHEC O157 that produces Shiga-like toxin
What are the renal features of HUS (2)
Oliguria
Creatinine
What are the haemolytic features of HUS (2)
Jaundice
Conjunctival pallor
How does AKI manifest in HUS
a child is infected with E. coli and develops the classical bloody diarrhoea associated with that. It produces a Shiga-like toxin (like shigella’s toxin) which is capable of binding to endothelial cells within the kidney. It enters these cells and damages them. This damaged endothelium attracts widespread platelet plug formation. This leads to microthrombi which shear red blood cells. The end result is an acutely dysfunctional kidney – AKI – alongside a haemolytic anaemia.
How does HUS cause uraemia
The endothelial damage to make a dysfunctional kidney reduces kidney function which means compounds such as urea are not excreted leading to uraemia
Causes of DIC (6)
Pancreatitis Sepsis Obstetric complications Cancers Trauma ABO reaction
Blood results of DIC (4)
Platelets↓
Fibrinogen ↓
FDPs ↑
D-dimer ↑
Clotting features of DIC (2)
Prolonged APTT
Prolonged PT
What is the pathology behind TTP
Defunct ADAMTS-13 enzyme
What is the 6 things in TTP
ADAMTS
Antiglobulin (Coombs) negative Decreased platelets AKI MAHA Temperature Swinging CNS signs
Neurological manifestations of TTP? (6)
Neurologic manifestations include alteration in mental status, seizures, hemiplegia, paresthesias, visual disturbance, and aphasia
What happens in TTP
Defunct ADAMTS-13 enzyme fails to break down clots forming through vWF leading to blood clots forming in smaller vessels
Which drug can cause haemolytic anaemia
Dapsone
Anti-leprosy ABx
Which infection can cause haemolytic anaemia
Plasmodium falciparum
What cause of anaemia would result in a positive Coombs test
AI
What are the 2 types of a positive Coombs test and what do they indicate
Warm - above 37
IgG antibodies
Cold - below 37
IgM antibodies
What causes +ve warm Coombs’ test (3) and what antibody
IgG antibodies Idiopathic
SLE
CLL
What causes +ve cold Coombs’ test (3) and what antibody
IgM Antibodies
Idiopathic
Mycoplasma
Mononucleosis
Which thrombosis often manifests during pregnancy
Anti-phospholipid syndrome
Clinical features of APL syndrome (5)
Recurrent miscarriages (3+)
VTE
Stroke/MIs, HTN (arterial problems)
Livedo reticularis (mottled)
Ix for APL syndrome (2)
Anti-cardolipin +ve
Lupus anti-coagulant test +ve
Clinical features of PRV (4)
Older (~60)
Asymptomatic
Aquagenic pruritis
Hyperviscosity syndrome
Ix for PRV (4)
Elevated Hb & haematocrit
+/- Thrombocytosis
What is PRV and what happens in it
A Philadelphia chromosome negative myeloproliferative disorder which involves JAK2 leading to RBC proliferation independent of EPO
Which gene is affected in PRV
JAK2 V617F +ve
What happens in myelofibrosis
Fibrosis in response to a BM malignancy
What is associated with myelofibrosis
Moderate JAK2 mutation association
Age of myelofibrosis
Over 65
RF for myelofibrosis
Radiation
Ix for myelofibrosis
BM aspirate showing dry tap fibrosis
Blood film shows tear drop cells
What do tear drop cells on a blood film suggest
Myelofibrosis
What does aplastic crisis occur in
SCA and hereditary spherocytosis
What happens in aplastic anaemia
Aplastic anaemia typically arises from an autoimmune reaction to the haematopoietic stem cells of the BM. This leads to complete BM failure as all cell lines are affected
RFs of aplastic anaemia
Radiation and some infections (including EBV, HIV
Ix for aplastic anaemia (3)
FBC showing pancytopenia
EPO raised
BM aspirate hypocellular
Features of aplastic anaemia
Anaemia features:
+ EPO raised
Thrombocytopaenia:
Bleeding
Petechiae
Leucopoenia:
Sepsis
Recurrent infections
