Haematology Flashcards
What is fetal haemoglobin
2 alpha, 2 gamma subunits
Greater affinity for oxygen (bind more easily, harder to release)
Fetal haemoglobin production starts to decrease at 32-36 weeks (replaced by adult haemoglobin, all adult by 6 months)
What are the causes of anaemia in infants
Physiological anaemia of infancy (normal dip in Hb around 6-9 weeks)
Anaemia of prematurity (less time to get iron from mother, inadequate RBC production, reduced EPO levels, blood tests)
Blood loss
Haemolysis (haemolytic disease of the newborn, hereditary spherocytosis)
Twin-to-twin transfusion
What are the causes of anaemia in older children
Iron deficiency anaemia (dietary insufficiency)
Blood loss
Sickle cell anaemia
Thalassaemia
Leukaemia
Hereditary spherocytosis
Hereditary elliptocytosis
Sideroblastic anaemia
What are the causes of microcytic anaemia
TAILS
Thalassaemia
Anaemia of chronic disease
Iron deficiency anaemia
Lead poisoning
Sideroblastic anaemia
What are the causes of normocytic anaemia
3 As and 2 Hs
Acute blood loss
Anaemia of chronic disease
Aplastic anaemia
Haemolytic anaemia
Hypothyroidism
What are the causes of macrocytic anaemia
Impaired DNA synthesis
B12 deficiency
Folate deficiency
Alcohol
Reticulocytosis
Hypothyroidism
Liver disease
Drugs (azathioprine)
What are the symptoms of anaemia
Tiredness
Shortness of breath
Headaches
Dizziness
Palpitations
Worsening of other conditions
Pica and hair loss (with iron deficiency anaemia)
What are the generic signs of anaemia
Pale skin
Conjunctival pallor
Tachycardia
Raised respiratory rate
What are the signs of anaemia that are specific to iron deficiency
Koilonychia
Angular cheilitis
Atrophic glottis
Brittle hair and nails
What are the investigations for anaemia
Bloods (FBC, blood film, reticulocyte count, ferritin, B12, folate, bilirubin)
Direct Coombs test
Haemoglobin electrophoresis
What is the management for anaemia
Treat underlying cause
Consider blood transfusion
What are the causes of iron deficiency anaemia
Dietary insufficiency
Loss (heavy menstruation)
Inadequate absorption
Where is iron absorbed
Duodenum and jejunum
What medication interferes with iron absorption
PPIs
What is the management for iron deficiency anaemia
Treat underlying cause
Dietician input
Oral supplements
Consider blood transfusion
What is leukaemia
Cancer of particular line of stem cells in bone marrow
Unregulated production of blood cells (over production of one type, other types underproduced)
Get pancytopenia (low RBCs, low WBCs, low platelets)
What are the types of leukaemia that affect children
Acute lymphoblastic leukaemia (age 2-3)
Acute myeloid leukaemia (under 2s)
Chronic myeloid leukaemia
What are the risk factors for leukaemia
Radiation exposure (abdominal X-ray during pregnancy)
Conditions (Down’s, Klinefelter, Noonan)
How might a patient with leukaemia present
Persistent fatigue
Unexplained fever
Failure to thrive
Weight loss
Night sweats
Pallor
Petechiae and abnormal bruising
Unexplained bleeding
Abdominal pain
Generalised lymphadenopathy
Unexplained bone or joint pain
Hepatosplenomegaly
What are the investigations for leukaemia
Refer immediately if have: unexplained petechiae, hepatomegaly
Very urgent FBC (48 hours)
Blood film (shows blast cells)
Bone marrow biopsy
Lymph node biopsy
Staging (chest X-ray, CT, lumbar puncture, genetic analysis)
What is the management for leukaemia
Chemotherapy
Radiotherapy
Bone marrow transplant
Surgery
What are the complications of chemotherapy
Failure to treat
Stunted growth and development
Immunodeficiency and infection
Neurotoxicity
Infertility
Secondary malignancy
Cardiotoxicity
What is idiopathic thrombocytopenic purpura
Spontaneous low platelet count causing a non-blanching rash
A type II hypersensitivity reaction
Can be triggered by viral infections
Usually in under 10s
How might a patient with idiopathic thrombocytopenic purpura present
Rash appears over 24-48 hours
Bleeding (gums, epistaxis, menorrhagia)
Bruising
What are the investigations for idiopathic thrombocytopenic purpura
Urgent FBC (look at platelet count)
What is the management for idiopathic thrombocytopenic purpura
Usually no treatment needed
Monitor until platelets return to normal
If active bleeding or severe: prednisolone, IV immunoglobulins, blood transfusion, platelet transfusion
Education: avoid contact sports, avoid IM injections and lumbar punctures, avoid NSAIDs/aspirin/anticoagulants
What are the complications of idiopathic thrombocytopenic purpura
Chronic idiopathic thrombocytopenic purpura
Anaemia
Intracranial or subarachnoid haemorrhage
GI bleeding
What is sickle cell anaemia
Crescent shaped red blood cells (more fragile, easily destroyed)
A form of haemolytic anaemia
Prone to sickle cell crisis
Abnormal variant HbS
Autosomal recessive
Protective against malaria
What are the investigations for sickle cell anaemia
At risk mothers offered screening during pregnancy
Newborn heel prick test
What is the management for sickle cell anaemia
Avoid dehydration
Avoid triggers for crisis
Ensure vaccines up to date
Antibiotic prophylaxis (penicillin V)
Hydroxycarbamide (protects against crisis, stimulates fetal Hb production)
Bone marrow transplant
Blood transfusion
What are the complications of sickle cell anaemia
Anaemia
Increased risk of infection
Stroke
Avascular necrosis of large joints
Pulmonary hypertension
Priapism
Chronic kidney disease
Sickle cell crisis
Acute chest syndrome
What is the management for sickle cell crisis
Low threshold for admission
Treat any infection
Keep warm
Keep hydrated
Simple analgesia
Penile aspiration for priapism
What are the types of sickle cell crisis
Vaso-occlusive
Splenic sequestration
Aplastic
Acute chest syndrome
What is thalassaemia
Genetic defect in the protein chains that make up haemoglobin
Autosomal recessive
Red blood cells more fragile
Get splenomegaly
Bone marrow expands (susceptibility to fractures, pronounced forehead, pronounced cheekbones)
How might a patient with thalassaemia present
Fatigue
Pallor
Jaundice
Gallstones
Splenomegaly
Poor growth and development
Pronounced forehead and cheekbones
What are the investigations for thalassaemia
FBC
Haemoglobin electrophoresis
DNA testing
What is iron overload
Due to: faulty creation of RBCs, recurrent transfusions, increased iron absorption
Presentation: fatigue, cirrhosis, infertility, impotence, heart failure, osteoporosis, joint pain
Management: limit transfusions, iron chelation
What is the management for thalassaemia
Monitor FBC
Monitor for complications
Blood transfusions
Splenectomy
Iron chelation
Bone marrow transplant
What is hereditary spherocytosis
Sphere-shaped red blood cells
Fragile, easily destroyed (when passing through spleen)
Autosomal dominant
How might a patient with hereditary spherocytosis present
Jaundice
Anaemia
Gallstones
Splenomegaly
Episodes of haemolytic crisis
Aplastic crisis
What are the investigations for hereditary spherocytosis
Blood film (spherocytes)
FBC (high reticulocytes)
What is the management for hereditary spherocytosis
Folate supplements
Splenectomy
Blood transfusions
What is G6PD deficiency
X-linked recessive
Crisis triggered by: infection, medications (primaquine, nitrofurantoin, trimethoprim)
G6PD enzyme protects cells against reactive oxygen species damage
Get haemolysis of red blood cells
How might a patient with G6PD deficiency present
Neonatal jaundice
Anaemia
Intermittent jaundice
Gallstones
Splenomegaly
What are the investigations for G6PD deficiency
Blood film (heinz bodies)
G6PD enzyme assay
What is the management for G6PD deficiency
Avoid triggers
