Adult patient:
Clotted blood tube
(Serum gel separator clot activator tube)
Minimum blood volume: 5 mL
Paediatric patient:
Paediatric clotted blood tube
Number of vials: 2
Minimum blood volume: 1.6 mL
Authorisation code required
No
24 Hr available service
No
Method
Immunoassay
Reference interval
7.0 - 46.4 nmol/L
(Source: from manufacturer's kit insert)
Clinical indication
Investigation of patients with a high MCV and / or changes in red cell morphology on blood film suggestive of megaloblastic anaemia.
Result interpretation
Red cell and serum folate levels are low in megaloblastic anaemia due to folate deficiency.
In vitamin B12 deficiency, serum folate may be normal or raised, red cell folate normal or low.
Low serum folate with a normal red cell folate may be seen in systemic illness and with a short term decrease in folate intake.
Although red cell folate measurement more closely reflects tissue stores, serum folate measurement provides an early index of folate status.
Measurement of uncertainty
Frequency of measurement
Daily