Acetylcholinesterase, Amniotic Fluid
Use
The Acetylcholinesterase, Amniotic Fluid test is primarily used for diagnosing open neural tube defects such as anencephaly and spina bifida, and to a lesser extent, ventral wall defects. These conditions are linked to failures in the complete closure of the neural tube during the early embryonic period. The presence of acetylcholinesterase (AChE) in the amniotic fluid is a key marker for these defects, as it usually indicates that the enzyme has been contributed by the fetus due to the defect. Detecting AChE can guide further clinical management and decision-making regarding the pregnancy.
Special Instructions
Gestational age at amniocentesis is required to order this test. If not ordering electronically, provide gestational age on the specified form and send with specimen. Additionally, if chromosome studies are also requested, see the corresponding test instructions to ensure the specimen cannot be frozen.
Limitations
This test may yield false-positive results if there is blood contamination in the amniotic fluid sample or due to contamination from fetal calf serum. Proper specimen collection, handling, and clear documentation of gestational age are critical to minimize the risk of diagnostic confusion. The test should be performed in conjunction with alpha-fetoprotein (AFP) testing for more comprehensive diagnostic insights.
New York Approved
Methodology
Other (Polyacrylamide Electrophoresis)
Biomarkers
LOINC Codes
- 30106-9
- 30106-9
- 18185-9
Result Turnaround Time
3-7 days
Related Documents
For more information, please review the documents below
Specimen
Amniotic Fluid
Volume
1 mL
Minimum Volume
0.3 mL
Container
Amniotic fluid container
Collection Instructions
Specimen must be collected between 14 to 21 weeks gestation; 14 to 18 weeks is preferred.
Storage Instructions
Refrigerated storage is preferred, with room temperature storage acceptable for up to 14 days.
Causes for Rejection
Gross hemolysis and icterus do not cause rejection; clear guidelines for handling are provided.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 days |
| Refrigerated | 365 days |
| Frozen | 365 days |