Haematology Flashcards
What is MCV, MCH, MCHC and HCT on the FBC?
MCV: Mean corpuscular vol.
- Avg. Vol. of an RBC
MCH: Mean corpuscular haemoglobin
- Avg. mass of haemoglobin per RBC
MCHC: Mean corpuscular haemoglobin conc.
- The concentration of haemoglobin per given vol. of blood.
HCT: Haematocrit
- How many cells in relation to plasma.
What does pancytopaenia mean?
Low haemoglobin, neutrophils and platelets
What are three main groups of blood cells?
Red cells
White cells
Platelets
Blood investigations for anaemia?
FBC
- Hb
- MCV
- MCH
- Red cell count
Blood film
- Morphology of cells
Haematinics
- B12
- Folate
- Ferritin
- Iron
What is high haemoglobin levels called?
Polycythaemia
What is polycythaemia?
High haemoglobin levels
What is low haemoglobin levels called?
Anaemia
Causes of Polycythaemia (high levels of Hb)?
Primary
- PRV (haematological Ca.)
Secondary: High EPO
- Appropriate e.g. High altitude
- Inappropriate: Ca.
Reactive:
- Dehydration
- Diuretics
If someone has Raised urea, Normal creatinine and anaemia what is likely going on?
GI bleed.
WCC low or normal likely what type of infection?
Viral
WCC high likely what type of infection?
Bacterial
What is raised platelets called?
Thrombocytosis
Causes of thrombocytosis?
MOST COMMON
- Infection/inflammation
- Splenectomy
Primary
- as part of another myeloproliferative disorder
Reactive
- Iron deficiency
- Haemorrhage
- Severe haemolysis
- Postoperative trauma
- Infection, inflammation
- Malignancy
- Hyposplenism
What is thrombocytopaenia?
Low platelets
What might give you thrombocytopaenia?
Viral infection
Lupus
What might give you lymphopaenia (reduced)?
HIV
Steroids (common)/immunosuppression -
Lymphoma
Bone marrow failure
What might give you lymphocytosis (raised)?
Viral infections and bacterial infections
What is a microcytic hypochromic picture (in FBC results?), what is it associated with?
Raised platelets
Lowered MCV, MCH and MCHC
Low ferritin and high transferrin
Iron deficiency anaemia or thalassaemia
How might Von-Willibrands present?
Very positive FH of bleeding (male and female)
What blood test is abnormal in Von willibrands
Clotting screen - APTT
What happens to transferrin in iron deficiency anaemia?
Increases (as we measure free levels and it has nothing to bind to)
Causes of iron deficiency anaemia?
Blood loss
Malabsorption e.g. coeliac
Poor dietary intake (rarely a cause in UK)
Treatment of iron deficiency anaemia?
Oral iron (not well tolerated), ferrous sulphate is best.
If unable to take oral iron or needed rapidly then can do iron infusion
Never do blood transfusion
What may cause pancytopaenia with macrocytosis?
B12 deficiency
Folate deficiency
Liver disease
Hypothyroidism
Why do you get Pancytopenia with B12 and folate deficiency?
B12 is a co-enzyme needed to bring folate into cells and folate is needed for the manufacture for Nucleic acids (important especially in new cells) This affects rapidly dividing tissue such as bone marrow (hair and GI too)
Causes of B12 deficiency?
Pernicious anaemia is most common in the UK (no intrinsic factor)
Gastrectomy - as no acid to absorb it
Inadequate diet e.g. Vegans or vegetarians.
Intestinal causes e.g. crohns, ileal resection.
If you suspect pernicious anaemia what history and examination should you concentrate on?
Family Hx of other autoimmune diseases
Neurological examination, focus on vibration and touch (DCML)
Causes of folate deficiency?
Poor dietary intake - often chronic alcoholism
Malabsorption in coeliac disease
Increased use in pregnancy or haemolytic anaemia
Where is iron absorbed?
Stomach, duodenum and first bit of jejunum (where there is acid)
What bloods would you order in pernicious anaemia (low B12)? What would you find?
FBC - Anaemia
Blood film - Hypersegmented neutrophils
Low B12, Raised Folate
What is LDH in blood tests?
Lactate dehydrogenase, it is a general marker of disease and is raised in many conditions, such as cancer, HIV, HF, lung and liver disease, it shoots up in haemolysis.
How would you treat B12 deficiency?
B12 injection
No need for transfusion, and transfusion may cause harm (2’ to cardiomyopathy caused by the low B12)
What would you find in blood tests after giving B12 to check to see in treatment is working after 3 days?
Reticulocytes will have been raised (may not have corrected the anaemia yet though
B12 will be raised
Lower K+ and raised Na+
Blood results in haemolytic anaemia?
Reticulocytosis (increased immature RBCs)
+ve cooms tets
Haptoglobin very low
Lactate dehydrogenase
Clinical findings in haemolytic anaemia?
Organomegaly
Anaemia
Jaundice
How can you classify the different haemolytic anaemias?
Hereditary
- Membrane
- Enzyme
- Haemoglobin chain disorder
Acquired
What is the makeup of adult haemoglobin? What are the inherited haemoglobin chain haemolytic anaemic disorders?
2 Alpha, 2 Beta chains
B chain
- Sickle cell
- Haemoglobin E
- Thalassaemia
Alpha chains
- Alpha thalassaemia - doesn’t really affect people.
Geographical distribution of B-Thalassaemia?
Middle east, cyprus and greece
How does B-Thalassaemia present?
- 3-4 years old
- Tired, floppy baby, growth failure
- Protruding belly (organomegaly)
- Jaundice
- Flat bridged nose
How do you treat B thalassaemia?
Bone marrow transplant is curative (not always possible though)
Red cell infusion is treatment (although will cause iron overload)
- Normal treatment for iron overload is venesection, but can’t do this as anaemic
- So need to use a chelating agent - deferoxamine
What is myeloma?
Ca. of mature B cells
What are the features of myeloma (diagnostic and otherwise)?
CRAB
hyperCalcaemia
Renal impairment
Anaemia
Bone lesions & Bone pain (70%)
Diagnostic
- Paraprotein (can not be present if non-secretory)
- Lytic lesions
- +ve Bone marrow biopsy
Free light chains in bloods
What is the emergency scenario you need to exclude in an ‘off legs’ pt with Myeloma (or other Ca.)? Management?
Spinal cord compression
Fluids
Steroids
Bisphosphonates
Furosemide
Most common causes of hypercalcaemia in inpatient and outpatient?
Inpatient - Ca.
Outpatient - Hyperparathyroidism
Management of a bone marrow crisis?
- O2
- Analgesia
- Fluids
- Exchange transfusion
- Hydroxycarbomide (raises foetal Hb)
Complications of sickle cell? Prophylaxis?
Hyposplenism
- Can get encapsulated bacterial infection
Need to vaccinate for:
- Haemophilus
- Meningococcus
- Pneumococcus
Inheritance pattern for sickle cell?
Autosomal recessive
What is spherocytosis?
Autosomal dominant inherited membrane disorder, affected red cells are destroyed in the spleen.
Presentation of hereditary spherocytosis? (inc. blood tests).
Any age - Haemolytic anaemia, Splenomegaly, Jaundice (gallstones or haemolysis).
Positive FH
Raised MCV Raised Reticulocytes (immature red cells) MCHC raised
Management of hereditary spherocytosis?
Cholecystectomy and splenectomy
What happens to the levels of ferritin, transferrin in the different types of anaemia?
Iron deficiency anaemia
- Low ferritin
- Raised Transferrin
Anaemia of chronic disease
- Normal or raised ferritin
- Reduced transferrin
What conditions may cause a transient rise in the APTT, with no symptoms? (Dr Roy pre-surgery)
Factor 12 deficiency
Lupus - antiphospholipid
Repeat the bloods and if still raised should do test without antiphospholipids in vial
Would you ask for a clotting screen when on warfarin? What would you ask for instead?
No - ask for INR
What is the pathophysiology behind heparin induced thrombocytopenia?
Antibody forms against platelet-heparin complex and activates them - forming clots and lowering platelet level (as they have been activated).
What anticoagulant do you give in renal failure (<30 GFR)?
Unfractionated Hep
What are the common DOACs? Their mechanisms?
Rivaroxaban - Factor Xa
Apixaban - Factor Xa
Dabigatran - Antithrombin
What is the most common inherited bleeding disorder?
Haemophilia A
What is the presentation for platelet bleeding disorders/thrombocytopenia?
Bleeds
- Epistaxis
- Gums
- Haemoptysis, Haematemesis, Haematuria
Spontaneous bruising
Petechiae (<5mm) or Purpura (5-9mm)
Why do people with bleeding disorders have an increased risk of arthritis?
Bleeding into the joint (synovial vessels)
What type of stones do people with spherocytosis typically develop?
Bilirubin stone
Why do people with spherocytosis often need cholecystectomy/splenectomy?
Chole - for bilirubin stones
Splenectomy - eliminates anaemia (as less Red cells are destroyed) - curative in most patients.
Chole is mostly done at the time of splenectomy is stones are present.
Painless jaundice normally means?
Pancreatic Ca.
Where does iron usually deposit in haemachromotosis?
Heart
Liver
Skin
Pancreas
