Test Code CHRCB Chromosome Analysis, Congenital Disorders, Blood
Useful For
Diagnosis of congenital chromosome abnormalities, including aneuploidy, structural abnormalities, and balanced rearrangements
Reflex Tests
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
_M15A | Metaphases, 1-14 | No, (Bill Only) | No |
_M19 | Metaphases, 15-20 | No, (Bill Only) | No |
_MG19 | Metaphases, >20 | No, (Bill Only) | No |
_KTG2 | Karyotypes, >2 | No, (Bill Only) | No |
_STAC | Ag-Nor/CBL Stain | No, (Bill Only) | No |
Testing Algorithm
This test includes a charge for cell culture of fresh specimens and professional interpretation of results. Analysis charges will be incurred for total work performed, and generally include 2 banded karyograms and the analysis of 20 metaphase cells. If no metaphase cells are available for analysis, no analysis charges will be incurred. If additional analysis work is required, additional charges may be incurred.
This test is not appropriate for detecting acquired chromosome abnormalities. If this test is ordered with a reason for testing indicating a hematologic disorder, the test will be cancelled and CHRHB / Chromosome Analysis, Hematologic Disorders, Blood will be performed as the appropriate test.
A chromosomal microarray study (CMACB / Chromosomal Microarray, Congenital, Blood) is recommended as the first-tier test (rather than a congenital chromosome study) to detect clinically relevant gains or losses of chromosomal material for individuals with multiple anomalies not specific to well-delineated genetic syndromes, individuals with apparently nonsyndromic developmental delay or intellectual disability, and individuals with autism spectrum disorders.
Special Instructions
Method Name
Cell Culture with Mitogens followed by Chromosome Analysis
Reporting Name
Chromosomes, Congenital, BloodSpecimen Type
Whole bloodShipping Instructions
Advise Express Mail or equivalent if not on courier service.
Necessary Information
Provide a reason for testing with each specimen. The laboratory will not reject testing if this information is not provided, but appropriate testing and interpretation may be compromised or delayed.
Specimen Required
Submit only 1 of the following specimens:
Specimen Type: Whole blood
Container/Tube: Green top (sodium heparin)
Specimen Volume: 4 mL
Collection Instructions:
1. Invert several times to mix blood.
2. Other anticoagulants are not recommended and are harmful to the viability of the cells.
3. Label specimen as whole blood.
Specimen Type: Cord blood
Container/Tube: Green top (sodium heparin)
Specimen Volume: As much as possible
Collection Instructions:
1. Invert several times to mix blood.
2. Other anticoagulants are not recommended and are harmful to the viability of the cells.
3. Label specimen as cord blood.
Specimen Minimum Volume
2 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Whole blood | Ambient (preferred) | ||
Refrigerated |
Reference Values
An interpretive report will be provided.
Interpretation
When interpreting results, the following factors need to be considered:
-Some chromosome abnormalities are balanced (no apparent gain or loss of genetic material) and may not be associated with birth defects. However, balanced abnormalities often cause infertility and, when inherited in an unbalanced fashion, may result in birth defects in the offspring.
-A normal karyotype (46,XX or 46,XY with no apparent chromosome abnormality) does not eliminate the possibility of birth defects such as those caused by submicroscopic cytogenetic abnormalities, molecular mutations, and environmental factors (ie, teratogen exposure).
It is recommended that a qualified professional in Medical Genetics communicate all abnormal results to the patient.
Clinical Reference
1. McKinlay Gardner RJ, Amor DJ, eds. Amor, Gardner and Sutherland's Chromosome Abnormalities and Genetic Counseling, 5th ed. Oxford Monographs on Medical Genetics, 2018
2. Manning M, Hudgins L. Professional Practice and Guidelines Committee: Array-based technology and recommendations for utilization in medical genetics practice for detection of chromosomal abnormalities. Genet Med. 2010;12(11):742-745
3. Sheets KB, Crissman BG, Feist CD, et al. Practice guidelines for communicating a prenatal or postnatal diagnosis of Down syndrome: recommendations of the national society of genetic counselors. J Genet Couns. 2011;20(5):432-441
4. Practice Committee of the American Society for Reproductive Medicine. Evaluation and treatment of recurrent pregnancy loss: a committee opinion. Fertil Steril. 2012;98(5):1103-1111
5. Committee opinion no. 605: primary ovarian insufficiency in adolescents and young women. Obstet Gynecol. 2014;124(1):193-197
Day(s) Performed
Monday through Friday
Report Available
10 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest 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
88230, 88291- Tissue culture for Lymphocytes, Interpretation and report
88262 w/modifier 52-Chromosome analysis less than15 cells (if appropriate)
88262-Chromosome analysis with 15 to 20 cells (if appropriate)
88262, 88285-Chromosome analysis with greater than 20 cells (if appropriate)
88280-Chromosome analysis, greater than 2 karyotypes (if appropriate)
88283-Additional specialized banding technique (if appropriate)
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
CHRCB | Chromosomes, Congenital, Blood | 81862-5 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
52366 | Result Summary | 50397-9 |
52368 | Interpretation | 69965-2 |
52367 | Result | 82939-0 |
CG775 | Reason for Referral | 42349-1 |
52369 | Specimen | 31208-2 |
52370 | Source | 31208-2 |
52372 | Method | 85069-3 |
52371 | Banding Method | 62359-5 |
54630 | Additional Information | 48767-8 |
52373 | Released By | 18771-6 |
Forms
New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available: