Folate (Folic Acid)
(FolA)

Sample type:

(Serum )Gel-barrier tube (preferred) or red-top tube .

Use:

Detect folate deficiency; monitor therapy with folate; evaluate megaloblastic and macrocytic anemia; evaluate alcoholic patients and those with prior jejunoileal bypass for morbid obesity or those with intestinal blind-loop syndrome.

Precautions:

Certain drugs decrease folic acids like Alcohol, PAS, Ampicillin, Antimalarial, Erythromycin, Methotrexate, Oral contraceptives, Chloramphenicol, Penicillins Phenobarbital, Aminopterin, Tetracyclines, and Phenytoin. Avoid administration of radionuclide for at least 24 hours. Hemolysis gives a false elevated level. Iron deficiency anemia gives a false increase. Draw blood before the administration of the injection of B12.

Interfering factors:

Hemolysis may significantly increase folate values due to high concentrations of folate in red blood cells; therefore, hemolyzed samples are not suitable for this assay.

Pre analytical errors:

1) Drawing sample with anticoagulant.

2) Hemolysis; improper labeling Post errors:

1) Delayed report

2) Incorrect calculation

Corrective action:

Reject any sample with anticoagulant.