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Test Code QUAD1 Quad Screen (Second Trimester) Maternal, Serum


Necessary Information


In order to provide the best results, either answer the order entry questions or provide the required information using the Second Trimester Maternal Screening Alpha-Fetoprotein (AFP)/QUAD Screen Patient Information (T595) (see Special Instructions).



Specimen Required


Container/Tube: 

Preferred: Red top

Acceptable: Serum gel

Specimen Volume: 1 mL

Collection Instructions:

1. Do not draw specimen after amniocentesis as this could affect results.

2. Centrifuge immediately

Additional Information:

1. For an assessment that includes neural tube defect results, gestational age must be between 15 weeks, 0 days and 22 weeks, 6 days.

2. Assessments for trisomy 21 (Down syndrome) and trisomy 18 (Edwards syndrome) only are available between 14 weeks, 0 days and 22 weeks, 6 days.

3. Initial or repeat testing is determined in the laboratory at the time of report and will be reported accordingly. To be considered a repeat test for the patient, the testing must be within the same pregnancy and trimester, with interpretable results for the same tests, and both tests are performed at Mayo Clinic.

4. Maternal Serum Screening patient education brochure (T522) is available upon request.


Forms

1. Second Trimester Maternal Screening Alpha-Fetoprotein (AFP)/QUAD Screen Patient Information (T595) is required; see Special Instructions

2. If not ordering electronically, complete, print, and send a General Request (T239) with the specimen.

Secondary ID

113145

Testing Algorithm

See Prenatal Aneuploidy Screening and Diagnostic Testing Options in Special Instructions

Method Name

Immunoenzymatic Assay

Specimen Type

Serum

Specimen Minimum Volume

0.75 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Serum Refrigerated (preferred) 7 days
  Frozen  90 days

Reject Due To

Gross hemolysis Reject
Gross lipemia OK
Gross icterus OK

Reference Values

NEURAL TUBE DEFECTS

An AFP multiple of the median (MoM) <2.5 is reported as screen negative. AFP MoMs ≥2.5 (singleton and twin pregnancies) are reported as screen positive. 

 

DOWN SYNDROME

Calculated screen risks <1/270 are reported as screen negative, risks ≥1/270 are reported as screen positive.

 

TRISOMY 18

Calculated screen risks <1/100 are reported as screen negative, risks ≥1/100 are reported as screen positive.

 

An interpretive report will be provided.

Day(s) and Time(s) Performed

Monday through Friday; 8 a.m.-4:30 p.m.

Performing Laboratory

Mayo Clinic Laboratories in Rochester

CPT Code Information

81511