Ordering Recommendation

Alternate test when clinical/family history is classic for HHT. Test does not detect large duplications/deletions.

Mnemonic
HHT-FGS
Methodology

Polymerase Chain Reaction/Sequencing

Performed

Varies

Reported

28-35 days

New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation
Collect

Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).

Specimen Preparation

Transport 3 mL whole blood. (Min: 1 mL)

Storage/Transport Temperature

Refrigerated.

Unacceptable Conditions
Remarks
Stability

Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable

Reference Interval

By report

Interpretive Data

Background Information for Hereditary Hemorrhagic Telangiectasia (ACVRL1 and ENG) Sequencing
Characteristics:
Recurrent nosebleeds, telangiectases (mouth, face, hands, GI tract), arteriovenous malformations (lung, brain, liver, spine).
Incidence:
1:5,000-10,000
Inheritance:
Autosomal dominant
Penetrance:
Approaches 100 percent by age 40.
Cause:
  Pathogenic variants in the endoglin (ENG), activin A receptor type II-like 1 (ACVRL1 or ALK1), SMAD4 or other unidentified gene(s).
Clinical Sensitivity:
Approximately 75 percent
Methodology:
Bidirectional sequencing of the coding regions and intron-exon boundaries of ENG and ACVRL1, the 5' untranslated region of ENG, and a region of ACVRL1 intron 9 encompassing the CT-rich variant hotspot region.
Analytic Sensitivity and Specificity: 99 percent
Limitations:
Diagnostic errors can occur due to rare sequence variations. Regulatory region and intronic mutations, large deletions/duplications, and mutations in genes other than ENG and ACVRL1 will not be detected.

Compliance Statement C: For human genetic inheritable conditions and mutations. This test was developed and its performance characteristics determined by ARUP Laboratories. The U. S. Food and Drug Administration has not approved or cleared this test; however, FDA clearance or approval is not currently required for clinical use. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions.

Counseling and informed consent are recommended for genetic testing. Consent forms are available online.

Note
Hotline History
N/A
CPT Codes

81406 (ENG); 81479

Components
Component Test Code* Component Chart Name LOINC
0051575 HHT, Sequencing
2001357 HHT, Sequencing - Specimen
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Aliases
  • ACVRL1 and ENG sequencing
  • HHT sequencing
Hereditary Hemorrhagic Telangiectasia (ACVRL1 and ENG) Sequencing