Haematology Flashcards
What does serum contain?
Glucose, Electrolytes, proteins e.g. antibodies and hormones
What do red blood cells develop from?
reticulocytes which originate from myeloid stem cells
What are platelets made by?
megakaryocytes which develop from myeloid stem cells
What is the normal platelet count?
150-450 x10^9/L
Myeloid stem cells become myeloblasts, which can then become what?
Monocytes then macrophages
Neutrophils
Eosinophils
Mast cells
Basophils
What is Anisocytosis and what condition can it be seen in?
Variation in size of red blood cells
can be seen in myelodysplastic syndrome and many types of anaemia
What are Target cells and what conditions can they be seen in?
red blood cells with a central pigmented area surrounded by a pale area, surrounded by a ring of thicker cytoplasm on the outside. They look like a bull’s eye target.
These are mostly seen in iron deficiency anaemia and post-splenectomy
What are Heinz bodies and what conditions are they seen in?
individual blobs (inclusions) seen inside red blood cells. These blobs are denatured (damaged) haemoglobin.
They are mostly seen in G6PD deficiency and alpha-thalassaemia.
What are Howell-Jolly bodies and what conditions are they seen in?
blobs of DNA material seen inside red blood cells
seen after splenectomy , sickle cells and severe anaemia
In what condition would you see a high number of reticulocytes on blood film?
haemolytic anaemia
What are smudge cells and what condition are they seen in?
ruptured white blood cells that occur while preparing the blood film when the cells are aged or fragile.
They are particularly associated with chronic lymphocytic leukaemia.
What are spherocytes and what conditions are they seen in?
sphere-shaped red blood cells without the bi-concave disk shape.
They can indicate autoimmune haemolytic anaemia or hereditary spherocytosis.
State 4 causes of microcytic anaemia
T – Thalassaemia
A – Anaemia of chronic disease
I – Iron deficiency anaemia
L – Lead poisoning
S – Sideroblastic anaemia
state 5 causes of normocytic anaemia?
A – Acute blood loss
A – Anaemia of chronic disease
A – Aplastic anaemia
H – Haemolytic anaemia
H – Hypothyroidism
state 2 causes of macrocytic megaloblastic anaemia
B12 deficiency
Folate deficiency
State 3 causes of normoblastic macrocytic anaemia
Alcohol
Reticulocytosis (usually from haemolytic anaemia or blood loss)
Hypothyroidism
Liver disease
Drugs, such as azathioprine
What are some generic symptoms of anaemia?
Tiredness
Shortness of breath
Headaches
Dizziness
Palpitations
Worsening of other conditions, such as angina, heart failure or peripheral arterial disease
State 2 symptoms specific to iron deficiency anaemia
Pica
Hair loss
State 3 generic signs of anaemia
Pale skin
Conjunctival pallor
Tachycardia
Raised respiratory rate
State 4 signs specific to iron deficiency anaemia
Koilonychia
Angular cheilitis
Atrophic glossitis
brittle hair and nails
What is a key sign of haemolytic anaemia ?
Jaundice
What blood tests would you do in someone with anaemia of unknown cause?
Full blood count for haemoglobin and mean cell volume
Reticulocyte count
Blood film
Renal profile
Liver function bilirubin (raised in haemolysis)
Ferritin (iron)
B12 and folate
Intrinsic factor antibodies for pernicious anaemia
Thyroid function tests
Coeliac disease serology
Myeloma screening (e.g., serum protein electrophoresis)
Haemoglobin electrophoresis for thalassaemia and sickle cell disease
Direct Coombs test for autoimmune haemolytic anaemia
What type of anaemia does iron deficiency cause?
microcytic hypochromic anaemia
State 4 causes of iron deficiency anaemia
Insufficient dietary iron (e.g., restrictive diets)
Reduced iron absorption (e.g., coeliac disease)
Increased iron requirements (e.g., pregnancy)
Loss of iron through bleeding (e.g., from a peptic ulcer or bowel cancer)
What are some causes of a raised ferritin?
Inflammation (e.g., infection or cancer)
Liver disease
Iron supplements
Haemochromatosis
What does total iron-binding capacity do with iron deficiency anaemia?
increase
What are the 3 options for treating iron deficiency anaemia?
Oral iron (e.g., ferrous sulphate or ferrous fumarate)
Iron infusion (e.g., IV CosmoFer)
Blood transfusion (in severe anaemia)
State 3 causes of low B12
Pernicious anaemia
Insufficient dietary B12 (particularly a vegan diet, as B12 is mostly found in animal products)
Medications that reduce B12 absorption (e.g., proton pump inhibitors and metformin)
What causes pernicious anaemia?
autoimmune condition involving antibodies against the parietal cells or intrinsic factor
Where is vitamin B12 absorbed?
distal ileum
What neurological symptoms can vitamin B12 deficiency cause?
Peripheral neuropathy, with numbness or paraesthesia (pins and needles)
Loss of vibration sense
Loss of proprioception
Visual changes
Mood and cognitive changes
What 2 antibodies are used to diagnose pernicious anaemia?
Intrinsic factor antibodies (the first-line investigation)
Gastric parietal cell antibodies (less helpful)
What is the management of vitamin B12 deficiency?
IM Hydroxocobalamin
(3x weekly for 2w if no neuro symptoms, alternate days until improvement if neurological symptoms)
Maintenance depends on the cause:
Pernicious anaemia – 2-3 monthly injections for life
Diet-related – oral cyanocobalamin or twice-yearly injections
What is important to consider when a patient has B12 and folate deficiency
essential to treat the B12 deficiency first before correcting the folate deficiency. Giving patients folic acid when they have a B12 deficiency can lead to subacute combined degeneration of the cord, with demyelination in the spinal cord and severe neurological problems.
What inherited conditions can lead to chronic haemolytic anaemia?
Hereditary spherocytosis
Hereditary elliptocytosis
Thalassaemia
Sickle cell anaemia
G6PD deficiency
state 2 acquired conditions that can lead to haemolytic anaemia
Autoimmune haemolytic anaemia
Alloimmune haemolytic anaemia (e.g., transfusions reactions and haemolytic disease of newborn)
Paroxysmal nocturnal haemoglobinuria
Microangiopathic haemolytic anaemia
Prosthetic valve-related haemolysis
State 3 features of haemolytic anaemia
Anaemia
Splenomegaly
Jaundice
state 3 key investigations for haemolytic anaemia
Full blood count shows a normocytic anaemia
Blood film shows schistocytes (fragments of red blood cells)
Direct Coombs test is positive in autoimmune haemolytic anaemia
What is hereditary spherocytosis?
most common inherited haemolytic anaemia in northern Europeans. It is an autosomal dominant condition. It causes fragile, sphere-shaped red blood cells that easily break down when passing through the spleen.
presents with anaemia, jaundice, gallstones and splenomegaly. A notable feature is aplastic crisis in the presence of the parvovirus.
What would a blood tests/ film in someone with hereditary spherocytosis show?
Raised mean corpuscular haemoglobin concentration (MCHC) on a full blood count
Raised reticulocyte count due to rapid turnover of red blood cells
Spherocytes on a blood film
How is hereditary spherocytosis treated?
Treatment is with folate supplementation, blood transfusions when required and splenectomy. Gallbladder removal (cholecystectomy) may be required if gallstones are a problem
What is the inheritance pattern of G6PD deficiency?
X-linked recessive
What are some triggers of haemolytic anaemia in someone with G6PD deficiency?
infections, drugs or fava beans. Key medication triggers include ciprofloxacin, sulfonylureas (e.g., gliclazide) and sulfasalazine.
How does G6PD typically present?
jaundice (often in the neonatal period), gallstones, anaemia, splenomegaly and Heinz bodies on a blood film. Diagnosis can be made by doing a G6PD enzyme assay.
What may cold autoimmune haemolytic anaemia be secondary too?
lymphoma, leukaemia, systemic lupus erythematosus and infections (e.g., mycoplasma, EBV, CMV and HIV).
What is the management of autoimmune haemolytic anaemia?
Blood transfusions
Prednisolone
Rituximab (a monoclonal antibody against B cells)
Splenectomy
In what 2 situations may alloimmune haemolytic anaemia arise?
transfusion reactions
haemolytic disease of the newborn
What is the characteristic symptoms of paroxysmal nocturnal haemoglobinuria?
red urine in the morning, which contains haemoglobin and haemosiderin.
Other presenting features are anaemia, thrombosis (e.g., DVT, PE and hepatic vein thrombosis) and smooth muscle dystonia (e.g., oesophageal spasm and erectile dysfunction).
What is the inheritance pattern of thalassaemia?
autosomal recessive
What are some features of thalassaemia?
Microcytic anaemia
Fatigue
Pallor
Jaundice
Gallstones
Splenomegaly
Poor growth and development
What investigations are done for thalassaemia?
FBC - low MCV
Haemoglobin electrophoresis
DNA testing
Why may iron overload occur in a patient with thalassaemia?
Increased iron absorption in the gastrointestinal tract
Blood transfusions
What symptoms/complications may iron overload in thalassaemia cause?
Liver cirrhosis
Hypogonadism
Hypothyroidism
Heart failure
Diabetes
Osteoporosis
What chromosome is affected in alpha-thalassaemia?
16
What are the management options for alpha thalassaemia?
Monitoring
Blood transfusions
Splenectomy may be performed
Bone marrow transplant can be curative
What chromosome is affected in beta-thalassaemia?
11
What are the 3 types of beta-thalassaemia?
Thalassaemia minor
Thalassaemia intermedia
Thalassaemia major
What is the management of beta thalassaemia intermedia ?
causes more significant microcytic anaemia. Patients require monitoring and may need occasional blood transfusions. They may require iron chelation to prevent iron overload.
What are some bone changes seen in thalassaemia major
Frontal bossing (prominent forehead)
Enlarged maxilla (prominent cheekbones)
Depressed nasal bridge (flat nose)
Protruding upper teeth
What is the genetics behind sickle cell anaemia?
autosomal recessive
affecting gene for beta globin on chromosome 11
State 4 complications of sickle cell anaemia
Anaemia
Increased risk of infection
Chronic kidney disease
Sickle cell crises
Acute chest syndrome
Stroke
Avascular necrosis in large joints such as the hip
Pulmonary hypertension
Gallstones
Priapism (painful and persistent penile erections)
state 3 triggers for a sickle cell crisis
dehydration, infection, stress or cold weather.