25- NA: Folate Deficiency Flashcards
importance of folate
DNA production cycles = synthesis of adenosine, guanine and thymine
the final maturation of RBCs
recommended intake of folate?
100-150mcg daily
describe the criteria for diagnosing folate deficiency
megablastomic anaemia - present with combined B12 and folate deficiency
low reticulocytes
what are the three main classifications for causes of folate deficiency?
increased demand
decreased intake
decreased absorption
describe the causes that fall under increased demand leading to folate deficiency (3)
- periods of catabolic growth = e.g. pregnancy, breast feeding, growth spurts, cancer
- haemolysis and rapid cell turnover in SCD patients = bone marrow will try and compensate for unhealthy sickled RBCs, folate needed for RBC maturation
- urinary losses
describe the causes that fall under decreased intake leading to folate deficiency (3)
- poor diet
- elderly = tend to eat less
- patients with chronic alcohol intake = alcohol can interfere with folate metabolism, patients often don’t look after themselves
describe the causes that fall under decreased absorption leading to folate deficiency (4)
- folate antagonists = e.g. methotrexate - treats rheumatoid arthritis and haematological malignancies
- coeliac disease
- bowel surgery
- tropical sprue = malabsorption condition
treatment for folic acid deficiency?
oral folic acid supplements
how much folate is lost through cooking?
60-90%
what’s the absorption site of folate?
in the duodenum and jejunum
uses specialized transporters on the brush border membrane of enterocytes
there are two main divisions of macrocytic anaemia - megablastomic or non-megablastomic. which would folate deficiency fall under? what are the features of this anaemia?
falls under macrocytic megablastomic anaemia
features:
- low reticulocyte count = from errors in DNA synthesis/ replication inside the nucleus of RBC precursor cells
- low Hb, high MCV, normal MCHC = normal Hb content in each cell but big RBCs
