Haematology Flashcards
What is the structural difference between adult and foetal haemoglobin ?
Adults - 2 alpha and 2 beta subunits
Foetal - 2 alpha and 2 gamma subunits
What are some causes of anaemia in infancy ?
Physiological anaemia of infancy
Anaemia of prematurity
Blood loss
Haemolysis
Twin-twin transfusion where blood is unequally distributed between twins that share a placenta.
Haemolytic disease of the newborn
Hereditary spherocytosis
G6PD deficiency
What is physiological anaemia of infancy ?
There is a normal dip in haemoglobin around 6 to 9 weeks of age in healthy term babies.
High oxygen delivery to the tissues caused by the high haemoglobin levels at birth cause negative feedback. Production of EPO by the kidneys is suppressed causing reduced Hb by the bone marrow.
What are some reasons for anaemia in premature neonates ?
-Less time in utero receiving iron from the mother
-Red blood cell creation cant keep up with rapid growth in the first few weeks
-reduced EPO levels
-blood tests remove a significant portion of their circulating volume
What is the direct Coombs test ?
Can be used to check for immune haemolytic anaemia.
What are some causes of anaemia in older children ?
Iron deficiency anaemia
Blood loss
Sickle cell anaemia
Thalassaemia
Leukaemia
What is microcytic anaemia ?
Low MCV indicating small RBC
What is normocytic anaemia ?
Normal MCV indicating normal sized RBC
What is macrocytic anaemia ?
Large MCV indicating large RBC
What are some causes of microcytic anaemia ?
Thalassaemia
Anaemia of chronic disease
Iron deficiency anaemia
Lead poisoning
Sideroblastic anaemia
What are some causes of normocytic anaemia ?
Acute blood loss
Anaemia of chronic disease
Aplastic anaemia
Haemolytic anaemia
Hypothyroidism
What are the 2 types of macrocytic anaemia ?
Megaloblastic
Normoblastic
What is megaloblastic anaemia ?
The result of impaired DNA synthesis preventing the cell from dividing normally. Rather than it dividing it keeps growing into a large abnormal cell.
This is caused by vitamin deficiency.
What causes megaloblastic anaemia ?
B12 deficiency
Folate deficiency
What is normoblastic macrocytic anaemia ?
Alcohol
Reticulocytosis
Hypothyroidism
Liver disease
Drugs such as azathioprine
What are some symptoms of anaemia ?
Tiredness
SOB
Headaches
Dizziness
Palpitations
Worsening of other conditions
What are some symptoms specific to iron deficiency anaemia ?
Pica - dietary cravings for abnormal things like dirt
Hair loss - indicate iron deficiency anaemia
What are some generic signs of anaemia ?
Pale skin
Conjunctival pallor
Tachycardia
Raised RR
What are some signs that indicate iron deficiency anaemia ?
Koilonychia ( spoon shaped nails )
Angular chelitis
Atrophic glossitis ( smooth tongue due to atrophy of the papillae )
Brittle hair and nails
What are some initial investigations when suspecting anaemia ?
FBC
Blood film
Reticulocyte count
Ferritin
B12 and folate
Bilirubin
Direct Coombs test
How is severe anaemia treated ?
Blood transfusions
How is iron deficiency anaemia managed ?
Iron supplements
What are the types of leukaemia ?
Acute lymphoblastic leukaemia
Acute myeloid leukaemia
Chronic myeloid leukaemia
When do the types of leukaemia peak ?
Acute lymphoblastic leukaemia - 2-3 years old
Acute myeloid leukaemia - under 2 years old
What is the main environmental risk factor for leukaemia ?
Radiation exposure - abdominal X-ray during pregnancy
What conditions are associated with developing leukaemia ?
Down’s syndrome
Klinefelter’s syndrome
Noonan syndrome
Fanconi’s anaemia
How does leukaemia present ?
Persistent fatigue
Unexplained fever
Failure to thrive
Weight loss
Night sweats
Pallor
Petechiae
Unexplained bleeding
Abdominal pain
Generalised lymphadenopathy
Unexplained or persistent bone or joint pain
Hepatosplenomegaly
What investigations should be performed to establish a diagnosis of leukaemia ?
FBC
Blood film
Bone marrow biopsy
Lymph node biopsy
What further tests may be required for staging leukaemia ?
CXR
CT scan
Lumbar puncture
Genetic analysis and immunophenotyping
What is the management of leukaemia ?
Chemotherapy
Radiotherapy
Bone marrow transplant
Surgery
What are some complications of chemotherapy ?
Failure to treat leukaemia
Stunted growth and development
Immunodeficiency and infections
Neurotoxicity
Infertility
Secondary malignancy
Cardio toxicity
What is idiopathic thrombocytopenic purpura ?
A condition characterised by idiopathic ( spontaneous ) thrombocytopenia ( low platelet count ) causing a purpurin rash ( non-blanching rash ).
What causes ITP ?
Caused by a type 2 hypersensitivity reaction.
It is caused by the production of antibodies that target and destroy platelets.
How does ITP present ?
Under 10 years old
Often recent viral illness
Bleeding ( from gums, epistaxis or Menorrhagia )
Bruising
Petechial or purpuric rash