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Test Code ACHE_ Acetylcholinesterase, Amniotic Fluid

Reporting Name

Acetylcholinesterase, AF

Useful For

Diagnosing open neural tube defects and, to a lesser degree, ventral wall defects

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Specimen Type

Amniotic Fld


Additional Testing Requirements


If chromosome studies are also requested, see CHRAF / Chromosome Analysis, Amniotic Fluid for specimen requirements. When requested with chromosome analysis, the specimen cannot be frozen.



Necessary Information


1. Gestational age at amniocentesis is required.

2. If not ordering electronically, provide gestational age on Second Trimester Maternal Screening Alpha-Fetoprotein / Quad Screen Patient Information (T595) and send with specimen.



Specimen Required


Container/Tube: Amniotic fluid container

Specimen Volume: 1 mL

Collection Instructions: Specimen must be collected between 14 to 21 weeks gestation; 14 to 18 weeks is preferred.


Specimen Minimum Volume

0.3 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Amniotic Fld Refrigerated (preferred) 365 days
  Frozen  365 days
  Ambient  14 days

Reference Values

Negative (reported as negative [normal] or positive [abnormal] for inhibitable acetylcholinesterase)

 

Reference values were established in conjunction with alpha-fetoprotein testing and include only amniotic fluids from pregnancies between 14- and 21-weeks gestation.

Day(s) Performed

Tuesday, Thursday

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information

82013

LOINC Code Information

Test ID Test Order Name Order LOINC Value
ACHE_ Acetylcholinesterase, AF 30106-9

 

Result ID Test Result Name Result LOINC Value
9287 Acetylcholinesterase, AF 30106-9
GACHE Gestational Age (ACHE) 18185-9

Interpretation

The presence of acetylcholinesterase in amniotic fluid is consistent with open neural tube defects and, to a lesser degree, ventral wall defects.

Clinical Reference

1. Douglas Wilson R, Van Mieghem T, Langlois S, Church P. Guideline No. 410: Prevention, Screening, Diagnosis, and Pregnancy Management for Fetal Neural Tube Defects. J Obstet Gynaecol Can. 2021;43(1):124-139.e8. doi:10.1016/j.jogc.2020.11.003

2. Palomaki GE, Bupp C, Gregg AR, Norton ME, Oglesbee D. Laboratory screening and diagnosis of open neural tube defects, 2019 revision: a technical standard of the American College of Medical Genetics and Genomics (ACMG). Genet Med. 2020;22(3):462-474

Report Available

3 to 7 days

Method Name

Polyacrylamide Electrophoresis