Haem I Flashcards
What is essential thrombocytosis and what investigations / results help to differ it from secondary thrombocytosis? [2]
Essential:
- Dysregulated megakaryocyte proliferation
- Platelet count consistently high
Secondary:
- Triggered by infection, trauma, bleeding, hyposplenism
- Transiently raised platelet count
Describe how you manage essential thrombocytosis (depending if they are low or high risk)
Low risk = > 40 OR platelet count < 1500, no hx of thrombosis or haemorrhage. no CV risk
- Aspirin alone
High risk: > 60 OR DM/HTN; platelet count > 1500; Hx of thrombosis or haemorrhage, CV risk
- Hydroxycarbamide and aspirin
How do you differentiate between an aplastic and sequestration crisis in SCA? [1]
Aplastic: reduced reticulocytes
Seq. crisis: increased reticulocytes
What is TPO? [1]
Where is it produced? [1]
What does it regulate ? [1]
Thrombopoietin (TPO):
TPO is produced by the liver and essential for the control of platelet production
Name 5 drugs which cause macrocytic anaemia?
Azathioprine
Methotrexate
Fluorouracil
Phenobarbital
Mercaptopurine
Trimethoprim
What are specific signs associated with anaemia of iron deficiency? [4]
- Koilonychia (spoon shaped nails)
- Angular stomatitis (inflammation of corners of mouth)
- Restless legs syndrome
- Hair loss
- Post-cricoid webs
What do raised ferritin levels indicate? [4]
Inflammation (e.g., infection or cancer)
Liver disease
Iron supplements
Haemochromatosis
Describe the management of IDA [3]
1ST LINE
- oral iron replacement (ferrous sulfate)
- 200 mg once daily
2ND LINE
- intravenous iron replacement
3rd LINE:
- Blood transfusion
Describe how Fe tests would help to diagnose ACD [3]
The clinical presentation of ACD is generally that of the underlying disorder
Serum ferritin:
- Normal or raised (due to release during inflammation)
Serum iron:
- Low
TIBC:
- Low
What are specific signs associated with anaemia of vit. B12 deficiency? [7]
- Glossitis
- Positive Rombergs test & neurological impairment - posterior column degeneration
- Decreased vibration sense - posterior column degeneration
- Ataxia - posterior column degeneration
- Hyperpigmentation of nails
- Petechiae: generally a late sign of vitamin B12 deficiency.
- Optic neuropathy
Describe the clinical features of pernicious anaemia
Peripheral neuropathy, with numbness or paraesthesia (pins and needles)
mild jaundice: combined with pallor results in a ‘lemon tinge’
Loss of vibration sense
Loss of proprioception
Visual changes
Mood and cognitive changes
Describe the treatment regime for pernicious anaemia
Intramuscular hydroxocobalamin is initially given to all patients with B12 deficiency, depending on symptoms:
No neurological symptoms
- 3 times weekly for two weeks
Neurological symptoms
- alternate days until there is no further improvement in symptoms
MAINTENANCE:
Pernicious anaemia
– 2-3 monthly injections for life of intramuscular hydroxocobalamin
Diet-related:
- oral cyanocobalamin or twice-yearly injections
Which investigations are used to diagnose folate deficiency? [1]
Red cell folate is a better measure of levels than serum folate, since levels are affected even with a short period of deficiency.
How do you treat folate deficiency? [1]
Folic acid is usually given as a once daily oral dose of 5 mg for up to four months.
What advice should you give pregnant women regarding folic acid intake? [1]
Folate deficiency causes an increased risk of which pathology? [1]
all women should take 400mcg of folic acid until the 12th week of pregnancy
Risk of neural tube defects
Define what is meant by: [3]
- Hereditary spherocytosis
- Hereditary elliptocytosis
Hereditary spherocytosis
- Autosomal dominant familial condition; autoantibodies produced against proteins in RBC membrane mean it causes a spherical shape when they pass through the spleen
- Can still perform adequately despite reduced SA
- Fragile and easily lysed
Hereditary elliptocytosis:
- Autosomal dominant familial condition; autoantibodies produced against proteins in RBC membrane mean it causes an ellipse shape
- Can still perform adequately despite reduced SA
- Fragile and easily lysed
Describe a patient with hereditary spherocytosis may present [4]
- Jaundice at birth
- However the onset of jaundice can be delayed for many years and some
patients may go through life with no symptoms and are detected only during
family studies - May eventually develop anaemia
- Splenomegaly
- Ulcers on the leg
- Chronic haemolysis leads to the formation of gall stones
What investigations would indicate either hereditary spherocytosis or hereditary elliptocytosis? [3]
- Raised mean corpuscular haemoglobin concentration (MCHC) on a full blood count
- Raised reticulocyte count due to rapid turnover of red blood cells
- Spherocytes / elpitocytes on a blood film
- EMA testing and cryohaemolysis test if results unequivocal from blood film
What is the treatment of hereditary spherocytosis or hereditary elliptocytosis? [5]
- Folate supplementation- indicated in moderate to severely affected individuals or those who are pregnant to avoid megaloblastic anaemia due to the relative folate deficiency that occurs when the rate of RBC production increases to compensate for the increased rate of haemolysis.
- Blood transfusions when required
- Splenectomy.
- Erythropoietin may reduce the need for transfusions in young infants until they can mount an adequate hematopoietic response to the haemolysis.
- Gallbladder removal (cholecystectomy) may be required if gallstones are a problem.
Describe the presentation of G6PD deficiency [4]
How can you diagnose this pathology? [1]
G6PD deficiency presents with:
- jaundice (often in the neonatal period)
- gallstones
- anaemia
- splenomegaly
- Heinz bodies on a blood film.
Diagnosis can be made by doing a G6PD enzyme assay.
Describe how you would treat a patient with hereditary spherocytosis in:
- neonates [2]
- infants (>28 days old), children, and adults [5]
Neonates:
- 1st line: supportive care +/- red blood cell transfusions
- 2nd line: folic acid supplementation
infants (>28 days old), children, and adults
- 1st line: supportive care +/- red blood cell transfusions
- 2nd line: folic acid supplementation
- 3rd line: splenectomy with pre-op vaccination regimen
- Consider: cholecystectomy or cholecystostomy
- Plus: post-splenectomy antibiotic pneumococcal prophylaxis
In the diagnosis of aplastic anemia, which parameter is typically reduced in the peripheral blood count?
A. Reticulocyte count
B. White blood cell count
C. Platelet count
D. Hematocrit
In the diagnosis of aplastic anemia, which parameter is typically reduced in the peripheral blood count?
A. Reticulocyte count
B. White blood cell count
C. Platelet count
D. Hematocrit
Mycoplasma pneumoniae
SCA
Hyposplenism
Hyposplenism
Hyposplenism
Hyposplenism
According to NICE guidelines, which laboratory test is considered the gold standard for confirming the diagnosis of sickle cell anemia?
a) Complete Blood Count (CBC)
b) Hemoglobin Electrophoresis
c) Serum Ferritin
d) Coagulation Profile
According to NICE guidelines, which laboratory test is considered the gold standard for confirming the diagnosis of sickle cell anemia?
a) Complete Blood Count (CBC)
b) Hemoglobin Electrophoresis
c) Serum Ferritin
d) Coagulation Profile
Describe the different types of alpha thalassaemias [4]
Alpha thalassemia minima:
- 1 defective alpha subunit
- Silent carriers: slightly reduced / normal MCV but no clinical symptoms
- Hypochromic and microcytic anaemia
Alpha thalassemia minor:
- 2 defective alpha subunits
- Hypochromic and microcyticnaemia
- The remaining two alpha genes produce nearly normal levels of RBCs
HbH disease:
- 3 defective alpha subunits
- Excess beta chains causes RBC membrane damage and intramedullary haemolysis AND does not release oxygen to tissues, causing increased RBC production
Hydrops fetalis, Bart’s hydrops (γ4):
- 4 defective alpha subunits
- Extreme affinity to O2: incompatible with life
Describe the bone deformities that can occur in B.T major [4]
Unusual bone formation:
* Facial deformities: frontal bossing, maxilla overgrowth, prominence of upper incisors, ‘chipmunk’ facies, dental malocculsion.
* Body habitus changes: typically short limbs due to early fusion of epiphyses. Skull, pelvis, ribs and spinal changes may be seen
* Osteopaenia/osteoporosis
* Bone pain
What are 4 blood film findings of hyposplenism [4]
Blood film: features of hyposplenism include Howell-Jolly bodies, Pappenheimer bodies, target cells and irregular contracted red blood cells.
In alpha thalassemia, the Hemoglobin H (HbH) disease results from the deletion of three alpha-globin genes. What is the recommended treatment for patients with HbH disease, according to NICE?
a) Blood transfusion
b) Hydroxyurea
c) Folic Acid supplementation
d) Hematopoietic stem cell transplantation
c) Folic Acid supplementation
