FISH Study: Prenatal Chromosome Identification
Additional Information:
UFHPL Test #: 30265
CPT Code(s):
- 88271
- 88273
- 88291
Collection Procedure:
-
Specimen Requirements:
- Amniotic Fluid: Aseptically collect approximately 1 cc of per week of gestational age in two sterile 15 mL conical centrifuge tubes and sequentially label the tubes. The initial 1 - 2 cc should not be included for chromosome studies (but may be utilized for AFP testing).
- Chorionic Villi: Collect 10 - 30 mg of utilizing aspiration medium containing sodium heparin.* After assessment of the appropriate amount and quality of villi, transfer to a sterile centrifuge tube with transportation medium.
Do not freeze or fix samples in any manner contrary to the maintenance of cell viability. Maintain sample sterility; keep all specimens at room temperature; and deliver samples to the laboratory within 24 - 48 hours. Ship specimens at room temperature for overnight delivery.
- Unacceptable Conditions:
- Frozen specimens
- Specimens greater than 48 hours old*
- Stability (collection to initiation of testing):
- Ambient: 24 - 48 hours*
- Frozen: Unacceptable
* Cell viability of specimens requiring cell culture may be compromised in specimens more than 48 hours old upon receipt. Refrigeration at 2° - 8° C may assist when a delay is not preventable. Do not freeze or place specimens directly on ice.
Contact UF Health Pathology Laboratories prior to submission (approved by consultation).
Use:
This test is used further characterize chromosome abnormalities as previously identified by conventional G-banding techniques in prenatal studies (e.g., marker chromosome identification, derivative chromosome content, breakpoint analysis, etc.).
Methodology:
Metaphase fluorescence in-situ hybridization analysis (FISH) for characterization of de novo chromosomal findings; requires concurrent classic cytogenetic analysis; not for standalone use
Reported:
10 - 21 days
Reference Values:
By report; interpretive
Performed:
Monday - Saturday
Interpretation Data:
-