Chromosome Analysis, Whole Blood (Constitutional)

Test Number 511035

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CPT

Contact CPT coding department at 800-222-7566, ext 6-8400.

Synonyms

Chromosome analysis
Constitutional disorders

~~Karyotype~~
Routine G-Banding

Chromosome analysis
Constitutional disorders

Test Details

Methodology

Lymphocyte culture with mitogen stimulation, colchicine arrest of cells in mitosis with predominantly early metaphases, methanol/acetic acid fixation, spread preparation, trypsin-Giemsa banding, chromosome analysis of 20 metaphases with preparation and analysis of multiple karyotypes. Other banded preparations are made as needed. Fluorescence in situ hybridization (FISH) ordered as needed (see test 510770).

Result Turnaround Time

5 - 13 days

Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.

Test Includes

20 cell microscopic analysis; G-banded karyotype analysis

Use

This test is used to evaluate congenital malformations, intellectual disability, growth problems, infertility, cryptorchidism, hypogonadism, amenorrhea (primary), abnormal/ambiguous genitalia, recurrent miscarriage, Turner syndrome, Klinefelter syndrome, Down syndrome or other suspected chromosomal disorders.

Evaluate congenital malformations, intellectual disability, growth problems, infertility, cryptorchidism, hypogonadism, amenorrhea (primary), abnormal/ambiguous genitalia, recurrent miscarriage, Turner syndrome, Klinefelter syndrome, Down syndrome or other suspected chromosomal disorders

Special Instructions

Pertinent medical findings must accompany request for chromosome analysis. Include the patient's name, age, and suspected diagnosis. If cord blood or fetal blood is received, test number will be changed to 511025 to exclude maternal origin of the sample obtained.

Limitations

This result does not exclude the possibility of subtle rearrangements below the resolution of cytogenetics or congenital anomalies due to other etiologies.

This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.

This result does not exclude the possibility of subtle rearrangements below the resolution of cytogenetics or congenital anomalies due to other etiologies.

This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.

Contraindications

Not for stillborn cases, skin biopsy, or placental villi

~~Not for stillborn cases, skin biopsy, or placental villi.~~

Not for stillborn cases, skin biopsy, or placental villi

Specimen Requirements

Specimen

Whole blood

Volume

5 mL (adults), 2 mL (neonates)

5 mL (adult~~), 1 to 2 mL (neonate~~)

5 mL (adults), 2 mL (neonates)

Minimum Volume

2 mL

Container

Green-top (sodium heparin) tube

Collection Instructions

Using sterile technique, collect 5 mL of blood into a green-top (sodium heparin) tube or syringe. Invert the tube several times to prevent coagulation. Specimens should be sent the same day as collected. Use of improper anticoagulant and/or frozen specimen cannot be processed.

Venipuncture: Thoroughly cleanse the area with a Betadine® scrub or similar preparation followed by a rinse with 70% alcohol (ethanol may be used instead of isopropyl and is less toxic). Collect 1 to 10 mL of blood into a heparinized tube. Invert the tube several times to prevent coagulation. If a Vacutainer® is used, let off any remaining vacuum by inserting a hypodermic needle or loosening the top briefly.

Skin lancet puncture: Thoroughly cleanse the site (finger, earlobe or newborn child's heel) by the above method. Rinse a sterile Pasteur pipet or TB syringe with approximately 0.5 mL of sterile heparin, and aspirate blood into it. Care must be taken to use only blood within the sterilized site; dripping blood may be removed with a sterile gauze pad. The blood-heparin mixture may be placed into a sterile tube for transport.

Specimens must be sent the same day as collected and arrive in the laboratory Monday through Saturday and within 72 hours of collection.

Storage Instructions

Specimen should be sent to the laboratory immediately. Maintain specimen at room temperature. Specimens may be refrigerated if there is a delay in shipment. Do not freeze.

Causes for Rejection

Upon receipt, suitability of specimen will be determined by the Cytogenetics laboratory.

~~Hemolysis; specimen clotted; use of improper anticoagulant; frozen specimen. Upon receipt, suitability of blood specimen will be made at~~ the Cytogenetics laboratory.