Macrocytic Anaemia Flashcards
define macrocytic anaemia
red cells are large
two types of macrocytic anaemia
- genuine (true)
2. spurious (false)
two types of genuine (true) macrocytic anaemias
megaloblastic
non-megaloblastic
causes of megaloblastic anaemia
B12 deficiency
folate deficiency
drugs
rare inherited abnormalities
causes of non-megaloblastic macrocytic anaemia
alcohol
liver disease
hypothyroidism
marrow failure (myelodysplasia, myeloma or aplastic anaemia)
two causes of spurious macrocytic anaemia
- reticulocytosis
2. agglutination
what is reticulocytosis?
increased reticulocytes due to marrow response to acute blood loss
define agglutination
cold agglutinins are clumping of red cells at cold temperature and it is seen/ diagnosed as one large cell
define pernicious anaemia
AI condition resulting in destruction of gastric parietal cells
what does pernicious anaemia cause?
inability to secrete intrinsic factor leading to deficiency of B12
associations with pernicious anaemia
atrophic gastritis
personal/FH of AI disorders (hypothyroid, vitiligo, Addison’s)
presentation of B12/folate deficiency
anaemia= tiredness, SOB weight loss, diarrhoea infertility glossitis angular cheilitis jaundice (pernicious anaemia) B12 only= neurological
why does pernicious anaemia present with jaundice?
intramedullary haemolysis
red cells die prematurely releasing Hb and LDH, Hb is converted to bilirubin causing jaundice
neurological presentations of B12 deficiency
dorsal column
neuropathy
dementia
psychiatric
diagnosis of macrocytic anaemia
FBC blood film assay of B12 and folate levels antibodies (pernicious anaemia) Schilling's for B12 bone marrow measure metabolites and holotranscobalamin
