Ordering Recommendation

Molecular DNA test to confirm a diagnosis of biotinidase (BTD) deficiency when biotinidase enzymatic activity is low. To diagnose or rule out BTD deficiency, refer to Biotinidase, Serum (with Paired Normal Control) (0093362).

Mnemonic

BTD FGS

Methodology

Polymerase Chain Reaction/Sequencing

Performed

Varies

Reported

7-14 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

Interpretive Data

Background information for Biotinidase Deficiency (BTD) Sequencing:
Characteristics: Ataxia, hypotonia, developmental delay, respiratory problems, seizures, vision problems, hearing loss, alopecia, rash, candidiasis, metabolic ketolactic acidosis, organic aciduria and mild hyperammonemia.
Incidence: 1 in 60,000.
Inheritance: Autosomal recessive.
Penetrance: Unknown.
Cause: Deleterious BTD gene mutations.
Clinical Sensitivity: 99 percent.
Methodology: Bidirectional sequencing of the entire BTD coding region and intron-exon boundaries.
Analytical Sensitivity & Specificity: 99 percent.
Limitations: Diagnostic errors can occur due to rare sequence variations.  Regulatory region mutations, deep intronic mutations and large deletions/duplications will not be detected.

This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.

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

Compliance Category

Laboratory Developed Test (LDT)

Note

Hotline History

N/A

CPT Codes

81404

Components

Component Test Code* Component Chart Name LOINC
0051731 Biotinidase Deficiency (BTD) Sequencing 50398-7
2001339 BTD FGS Specimen
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.

Aliases

  • BTD mutation testing
Biotinidase Deficiency (BTD) Sequencing