Haematology Flashcards
What is vitamin b12 used in ?
For red blood cell development and also maintenance of the nervous system.
Causes of b12 deficiency
- pernicious anaemia = most common cause
- post gastrectomy
- vegan diet or a poor diet
- disorders/surgery of terminal ileum (site of absorption)
- Crohn’s: either diease activity or following ileocaecal resection - metformin (rare)
Features of b12 deficiency
- macrocytic anaemia
- blood film: hypersegmented neutrophils - sore tongue and mouth
- neurological symptoms
- the dorsal column is usually affected first (joint position, vibration) prior to distal paraesthesia - neuropsychiatric symptoms: e.g. mood disturbances
Causes of macrocytic anaemia
- vitamin b12 deficiency
- folate deficiency
- Liver disease/alcoholism
- Hypothyroidism
Causes of microcytic anaemia
- Iron deficiency
2. Thalassemia
Causes of normocytic anaemia
- Acute blood loss
2. Chronic renal disease
Features of macrocytic anaemia
- Loss of appetite/weight
- Brittle nails
- Tachycardia
- Diarrhoea
- Fatigue
- Fake skin (lips and eyelids)
- Dyspnoea
- Poor concentration/confusion
- Memory loss
Investigations for macrocytic anaemia
FBC – check for enlarged RBC and anaemia (MCV(high))
Haematocrit levels = low
Haemoglobin levels
Blood film to identify megaloblastic anaemia
–> hypersegmented polymorphoneucleated cells
LFT
TFT
Features of iron deficiency anaemia
- Fatigue
- Shortness of breath on exertion
- Palpitations
- Pallor
- Nail changes: this includes koilonychia (spoon-shaped nails)
- Hair loss
- Atrophic glossitis
- Post-cricoid webs
- Angular stomatitis
Investigations for iron deficiency anaemia
FBC:
- low Hb
- low MCV
- low ferritin
Blood film:
- microcytic hypochromic RBC
- poikilocytosis
- dimorphic RBCs
Endoscopy:
R/O malignancy
What is aplastic anaemia?
This type of anaemia occurs when your body fails to produce enough new blood cells
Features of aplastic anaemia
- normochromic, normocytic anaemia
- leukopenia with
thrombocytopenia - features of acute lymphoblastic or myeloid leukaemia
Symptoms:
- fatigue
- SOB
- tachycardia
- pallor
- headache
- fever
- failure to thrive
- jaundice
- murmurs
Investigations for aplastic anaemia
Blood:
- pancytopenia
- reticulocyte
Bone marrrow biopsy
- fewer cells than normal
What is sickle cell anaemia?
autosomal recessive condition that results for synthesis of an abnormal haemoglobin chain termed HbS
- more common in afro Caribbean decent
When do symptoms develop in sickle cell anaemia?
don’t tend to develop until 4-6 months when the abnormal HbSS molecules take over from fetal haemoglobin.
Symptoms of sickle cell anaemia
- Episodes of pain
- swelling of hands + feet
- frequent infections
- Vision disturbances
- delayed growth/puberty
Investigations for sickle cell anaemia
Definitive diagnosis = haemoglobin electrophoresis
Blood film: crescent moon
What is G6PD deficiency anaemia?
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the commonest red blood cell enzyme defect.
- more common = Mediterranean and Africa
- inherited in an X-linked recessive fashion.
- Many drugs can precipitate a crisis as well as infections and broad (fava) beans
Features of G6PD deficiency anaemia
- neonatal jaundice
- intravascular haemolysis
- gallstones are common
- splenomegaly may be present
- Heinz bodies on blood films.
- Bite and blister cells may also be seen
Investigations for G6PD deficiency anaemia
Diagnosis made using G6PD enzyme assay
Drugs causing G6PD deficiency anaemia
- anti-malarials: primaquine
- ciprofloxacin
- sulph- group drugs: sulphonamides, sulphasalazine, sulfonylureas
Define haemolytic anaemia
a disorder in which red blood cells are destroyed faster than they can be made.
Causes of haemolytic anaemia
autoantibodies, medications, and underlying malignancy
hereditiary
Signs & Symptoms of haemolytic anaemia
Pallor jaundice Fatigue SOB dizziness splenomegaly
Investigations for haemolytic anaemia
Bloods:
- low hb
- high MCHC
- increase reticulocyte
Film:
- RBC fragment
- schistocytes
- spherocytes
- reticulocyte
- nucleated RBC
Coombs test= positive
- immune mediated
What is idiopathic thrombocytopenic purpura (ITP)?
Immune-mediated reduction in the platelet count.
Symptoms for ITP
- petichae, purpura
- bleeding (e.g. epistaxis)
- catastrophic bleeding (e.g. intracranial)
Blood findings for ITP
Low platelet