Amyloidosis, Transthyretin-Associated Familial, Reflex, Blood
Use
This test is used for the diagnosis of adult individuals suspected of having transthyretin-associated familial amyloidosis, which is an autosomal dominant disorder resulting from variants in the transthyretin gene. The presence of a gene variant may lead to unstable amyloidogenic transthyretin protein, causing progressive symptoms like sensorimotor neuropathy, cardiomyopathy, and more, often culminating in cardiac or kidney failure. Through mass spectrometry, this test evaluates the transthyretin protein structure, followed by DNA sequence analysis of the TTR gene for structural changes identified.
Special Instructions
Not provided.
Limitations
Mass spectrometry might not identify gene variants resulting in a protein change less than 10 atomic mass units, or frequent nondisease-causing alterations. As over 12% of the population has certain innocuous alterations, molecular testing is sometimes necessary to confirm findings. Technical assay limitations like homology and high GC content can also hinder effective evaluation of the TTR gene.
New York Approved
Methodology
Mass Spectrometry (Affinity Chromatography/MS)
Biomarkers
Transthyretin (TTR)
Protein
LOINC Codes
- 94864-6 - TTR-assoc familial amyloidosis Pnl Bld
- 94860-4 - TTR Bld Qn
- 94863-8 - TTR width at half height Bld Qn
- 94862-0 - TTR 2 Bld Qn
- 94861-2 - TTR - TTR 2 MDiff Bld
- 51968-6 - Gene dis anl interp-Imp
- 69047-9 - Geneticist review
- 18771-6 - Provider signing name
Result Turnaround Time
3-9 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
3 mL
Minimum Volume
0.5 mL
Container
Lavender top (EDTA) or Yellow top (ACD)
Collection Instructions
Invert several times to mix blood. Send whole blood specimen in original tube. Do not aliquot.
Causes for Rejection
Gross hemolysis: OK; Gross lipemia: OK; Gross icterus: OK
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 4 days |
| Refrigerated | 4 days |