Microcytic anaemia Flashcards
What MCV range is classified as microcytic?
<80
What are causes of microcytic anaemia?
Iron deficiency
Thalassemia
Sideroblastic anaemia
Chronic disease
What is the most common anaemia worldwide?
Iron deficiency anaemia
What is iron used for in the body?
Absorbed and circulates bound to transferrin. Stored as ferritin or incorporated into core of haemoglobin
Allows oxygen to be carried around the body.
Component of myoglobin (stores and releases oxygen to muscle tissues)
DNA synthesis and repair
Detoxification
Other uses
What does Fe deficiency cause?
Impaired haemoglobin synthesis
What are causes of Fe deficiency
Malnutrition
Breastfeeding for too long (not good source of Fe)
Malabsorption eg Coeliac, IBD
Menorrhagia (long periods)
Hookworm (most common worldwide cause, causes GI bleeding)
In elderly = red flag for colon cancer bleeding needing urgent endoscopy
Decreased haemoglobin synthesis result in m_____ anaemia
Microcytic
What are symptoms of iron deficiency anaemia?
Fatigue
Weakness
Koilonychia (concave shaped nails)
Angular stomatitis (ulceration at corners of mouth)
Atrophic glossitis (enlarged tongue)
What investigations would be carried out for suspected iron deficient anaemia?
FBC (to see microcytic)
Blood film: Hypochromic RBCs,
Target cells (non-specific bullseye pattern of cells)
Howell Jolly bodies (non-specific nucleated RBCs)
Fe studies:
Decreased serum Fe
Decreased ferritin
Decreased transferrin saturation
Increased TIBC (total iron-binding capacity)
If there is an iron deficiency in >60, what else should be carried out?
Endoscopy
What is the treatment for iron deficiency?
Ferrous sulphate
What are side effects of ferrous sulphate?
Diarrhoea/ constipation
Black stool
If ferrous sulfate is poorly tolerated, what can be considered instead?
Ferrous gluconate
What is thalassemia?
Abnormal inherited blood disorders characterised by abnormal haemoglobin production
Haemoglobinopathy
What are the two main types of thalassemia?
Alpha and beta (to do with what part of haemoglobin molecule is affected)
What is alpha thalassemia?
Deficiency or absence of alpha-globin chains in haemoglobin.
Severity depends on number of affected genes (get 2 from each parent)
Deletions from 4 genes on chromosome 16
Associated with an abnormal haemoglobin isoform
What other condition is alpha thalassemia associated with?
Choriocarcinoma
What is beta thalassemia
Deficiency of absence of beta-globin chains in haemoglobin
Depends on mutations in these genes (1 from each parent)
Mutations of 2 genes on chromosome 11
Get normal haemoglobin isoforms, just depletion of beta-chains.
What are common symptoms of thalassemia?
Anaemia, splenomegaly, hepatomegaly, bone deformities, growth retardation, jaundice, fatigue and weakness
“Chipmunk faces” = massively enlarged forehead and cheekbones due to extramedullary haematopoiesis, so is RBC production here
Often get gallstones and failure to thrive
How is suspected thalassemia investigated?
FBC
Blood film = hypochromic RBCs, target cells, microcytic anaemia with increased reticulocytes.
Haemoglobin electrophoresis
X-ray showing “hair on end” signs for increased bone marrow activity
How do you treat thalassemia?
Regular blood transfusions
Iron chelation therapy (to manage iron overload from having regular transfusions)
After age of 6, can have splenectomy (due to splenomegaly /overactive spleen destroying RBCs contributing to anaemia)
Folate supplements
Bone marrow stem cell transplantation
What are side effects of iron chelation therapy?
Deafness
Cataracts
Thalassemia is often found where what other condition is present?
Malaria
Is alpha or beta thalassemia more common?
Beta thalassemia
