RBC folate Test

Your doctor may order an RBC folate test if your serum folate levels are low and he/she suspects that you also have low RBC folate. 

You may show the following symptoms of folate deficiency:

• Anaemia
• Extreme tiredness
• Lack of energy
• Breathlessness
• Noticeable heartbeats (palpitations)
• Feeling faint
• Headaches
• Pale skin
• Loss of appetite and weight loss
• Reduced sense of taste
• Diarrhoea
• Muscle weakness
• Numbness and tingling in the feet and hands
• Depression

Vitamin B12 is required for our cells to absorb folate. Therefore, a low level of RBC folate may also be seen in vitamin B12 deficiency. Symptoms related to vitamin B12 deficiency are: 

• Pale yellow tinge to your skin
• Mouth ulcers
• Pins and needles sensations (tingling)
• Depression
• Irritability
• Difficulty walking
• Sore and red tongue
• Disturbed vision
• Changes in the way you feel, think and behave
• A decline in mental abilities, such as memory, understanding and judgement (dementia)

You may be asked to avoid eating for eight hours before the test. Your doctor may also advise you to avoid alcoholic beverages before the test. 

Drugs such as methotrexate, aminopterin,  phenytoins, oral contraceptives and phenobarbital may decrease the level of RBC folate. If you are on any medications, please inform your doctor.

A blood sample is ordered for the RBC folate test. Your healthcare practitioner will explain the steps of the test to you before it is conducted. The sample of blood will be drawn from a vein in your arm in the following manner:

• A lab technician will tie a tourniquet on your upper arm. This helps slow down blood circulation so the right vein can be located.
• He/she will then clean the skin above the vein with an antiseptic solution and insert a sterile needle to withdraw the required amount of blood. 
• After the sample is drawn, the technician will remove the needle and cover the site with a cotton pad. 

If blood tests make you feel dizzy or faint, please inform your doctor or nurse so that they can look after you better. You may experience a pricking sensation when the needle goes in, but this will subside soon. After the test, some people get a temporary bruise at the puncture site. If it doesn’t fade away in a few days, please talk to your doctor.

Normal results:

• Adults: 140-628 ng/mL
• Children: More than 160 ng/mL

Abnormal results:

Low levels of RBC folate are reported as abnormal. Abnormal results may be due to:

• Untreated folate deficiency
• Vitamin B12 deficiency

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.