Test Overview
Clinical Utility
7- and 8-dehydrocholesterol are biomarkers for the diagnosis of the cholesterol biosynthesis defect Smith-Lemli-Opitz syndrome (SLOS).
Cholesterol biosynthesis disorders present with multiple congenital anomalies (most) or neurological symptoms with cerebrotendenous xanthomas (CTX).
Cholestanol (5α-cholestan-3β-ol) is elevated in cerebrotendenous xanthomatosis (CTX).
Desmosterol is elevated in desmosterolosis.
Lanosterol may be elevated in Antley-Bixler Syndrome-1.
Lathosterol is elevated in lathosterolosis.
Sitosterol is elevated in sitosterolemia, which presents with xanthomas and accelerated atherosclerosis.
Method
Liquid chromatography-mass spectrometry (LC-MS)
Result Included
7-dehydrocholesterol (7-DHC); 8-dehydrocholesterol (8-DHC); cholestanol; desmosterol; lanosterol; lathosterol; sitosterol
Specimen
Specimen Type
Avoid gel separator tubes; SerumPlasma (Heparin)
Volume
Sample Volume
0.5 mL
Specimen Comment
Avoid gel separator tubes.
Pediatric
Volume
0.2 mL
Patient Preparation
Fasting specimen preferred.
Collection & Handling
Handling Information
Store and submit specimen protected from light in an amber vial.
Store and send frozen.
Rejection Criteria
| Criteria | Specification |
|---|---|
| Specimen | Not protected from light or gel separator tube |
Performance & Interpretation
Turnaround Time
30 days
Results
-
Sterol Profileµmol/LSee Table
Comment
Sterol Ref. Interval
(µmol/L)Clinical Elevation 7-dehydrocholesterol 0.3 - 2.2 SLOS 8-dehydrocholesterol 0.2 - 3.7 SLOS Cholestanol 0.0 - 8.6 CTX Desmosterol 0.5 - 6.7 Desmosterolosis Lanosterol 0.0 - 0.7 Antley-Bixler Syndrome-1 Lathosterol 0.0 - 0.0 Lathosterolosis Sitosterol 1.7 - 34.7 Sitosterolemia Notes: Cholestanol is 5α-cholestan-3β-ol. CTX is Cerebrotendenous Xanthomatosis. Lanosterol may be elevated in Antley-Bixler Syndrome-1. Cholesterol biosynthesis disorders present with multiple congenital anomalies (most) or neurological symptoms with xanthomas (CTX). Sitosterol is elevated in Sitosterolemia, which presents with xanthomas and accelerated atherosclerosis.
Referral Location
Canada
Interface & Setup
HL7 Interface Codes
| Order Code | Result Name | Result Codes | Units |
|---|---|---|---|
| STEROL SP | STEROL PROFILE | 63852 |
Test Version
Last Updated
2023-01-05