CAH (21-Hydroxylase Deficiency) Common Mutations, Fetal Cells

Test Code
91680


CPT Codes
81402

Includes
If amniotic fluid or chorionic villi sampling (CVS) is received, then an additional charge will be added for cell culture work (CPT code(s): 88235) if not already ordered


Preferred Specimen
10 mL amniotic fluid collected in a sterile plastic leak-proof container


Minimum Volume
10 mL amniotic fluid • 10 mg chorionic villi


Other Acceptable Specimens
10 mg chorionic villi collected in a sterile tube filled with sterile culture media • Cultured cells collected in each of two separate sterile T-25 flasks, 75% confluent


Instructions
Do not hold specimen; Forward to laboratory when specimen arrives.

Amniotic fluid: Normal collection procedure. Specimen stability is crucial. Store and ship at room temperature immediately. Do not refrigerate or freeze; Forward to laboratory when sample arrives.

1. Please call 1-866-GENE-INFO (1-866-436-3463) prior to submission.
2. Documentation of parental carrier status must be provided.
3. It is required that maternal cell contamination study, str analysis be ordered in conjunction with fetal testing. A separate tube of maternal blood (EDTA) is required for this test.

Amniocyte or chorionic villus (CVS) culture: Two sterile T-25 flasks, 75% confluent, filled with culture medium. Specimen stability is crucial. Store and ship at room temperature immediately. Do not refrigerate or freeze; Forward to laboratory when cells arrive.

Dissected chorionic villus (CVS) biopsy: 10-20 mg dissected chorionic villi collected in sterile tube, filled with sterile culture medium. Specimen stability is crucial. Store and ship at room temperature immediately. Do not refrigerate or freeze; Forward to laboratory when sample arrives.


Transport Container
Sterile plastic leak-proof container


Transport Temperature
Room temperature


Specimen Stability
Room temperature: 48 hours
Refrigerated: Unacceptable
Frozen: Unacceptable


Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Do not reject


Methodology
Electrophoresis • Minisequencing • Polymerase Chain Reaction (PCR)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule
Tues


Report Available
7-14 days


Clinical Significance
This test detects the presence or absence of 11 common mutations in the CYP21A2 gene associated with 21-hydroxylase deficient congenital adrenal hyperplasia (CAH) in a fetus. Parental variants must be known and included on this panel; parental reports must be provided to the laboratory with or prior to submission of fetal sample. Parental concurrent testing is also strongly recommended if parental testing was not performed at Quest Diagnostics (see Test codes CAH common mutations and CAH (21-Hydroxylase deficiency), Gene Sequencing. Please contact Quest genetic counselor at 866-436-3453 to discuss test coordination prior to submitting a fetal sample.

The common mutations included in this panel are: c.92C>T (p.Pro31Leu, P30L); c.293-13C>G (Intron 2G); c.332_339del8 (p.Gly111Valfs*21, G110del8nt); c.518T>A (p.lle173Asn, I172N); the Exon 6 Cluster (c.710T>A (p.lle237Asn, I236N), c.713T>A (p.Val238Glu, V237E), and c.719T>A (p.Met240Lys, M239K)); c.844G>T (p.Val282Leu, V281L), c.923dupT (p.Leu308 Phefs*6, F306+T); c.955C>T (p.Gln319*, Q318X); c.1069C>T (p.Arg357Trp, R356W); c.1360C>T (p.Pro454Ser, P453S); and CYP21A2*7 (30 kb deletion). Please note that the description/nomenclature of these mutations may vary from laboratory to laboratory. For full gene sequencing of CYP21A2, see CAH (21-Hydroxylase Deficiency), Gene sequencing.

Please call GeneInfo at 866-436-3463 to speak to a Quest genetic ounselor for assistance or questions.


Performing Laboratory
Quest Diagnostics Nichols Institute-San Juan Capistrano, CA
33608 Ortega Highway
San Juan Capistrano, CA 92675-2042



Last Updated: November 6, 2024


The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.