α-Fetoprotein (AFP), AChE, Amniotic Fluid With Reflex to Fetal Hemoglobin (Hb F)
Also known as: AFP, Alpha-Fetoprotein, AChE, Hb F, Amniotic Fluid
Use
Analysis of midtrimester amniotic fluid for detection of open neural tube and ventral wall defects
Special Instructions
Patient's gestational age must be between 12 weeks and 24 weeks for the interpretation of α-fetoprotein. State gestational age by ultrasound and/or last menstrual period (LMP) on the request form. Note that AChE false-positive and false-negative results are more frequent at gestational ages of less than 13 weeks or greater than 24.9 weeks. Optimal gestational age for detection of AChE is 14 to 18 weeks.
Limitations
This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.
Methodology
Immunoassay (CLIA)
Biomarkers
LOINC Codes
- 1832-5
- 29253-2
- 49051-6
- 41273-4
- 72486-4
- 30106-9
- 76479-5
- 28067-7
Result Turnaround Time
4-10 days
Related Documents
For more information, please review the documents below
Specimen
Amniotic Fluid
Volume
3 mL
Minimum Volume
Not provided
Container
Sterile plastic conical tube; do not use urine containers or tubes with rubber stoppers. Rubber is toxic to amniocytes.
Collection Instructions
Avoid contamination of amniotic fluid with maternal or fetal blood. As little as one drop of fetal blood can cause false-positive results during assay of amniotic fluid. Amniotic fluid should be collected by the attending physician.
Patient Preparation
The patient should have undergone ultrasound studies to verify fetal viability, detect multiple gestation, confirm gestational age, localize placenta, and detect fetal and uterine pathology.
Storage Instructions
Ship and maintain specimen at room temperature.
Causes for Rejection
Specimen found not to be amniotic fluid; gross contamination of amniotic fluid with maternal or fetal blood; quantity not sufficient for analysis