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Test Code LSDS Lysosomal Disorders Screen, Random, Urine


Ordering Guidance


This test is the recommended screening test for the initial workup of a suspected lysosomal disorder (LD) when the patient's clinical features are not suggestive of any specific LD.



Necessary Information


1. Patient's age is required.

2. Biochemical Genetics Patient Information (T602) is recommended. This information aids in providing a more thorough interpretation of results. Send information with specimen.



Specimen Required


Patient Preparation:

1. Do not administer low-molecular weight heparin before specimen collection.

2. Baby wipes or wipes containing soaps or lotions should not be used before specimen collection because these may interfere with results.

Supplies: Urine Container, 60 mL (T313)

Container/Tube: Clean, plastic urine container with no metal cap or glued insert

Specimen Volume: 12 mL

Pediatric Volume: 3.5 mL

Collection Instructions:

1. Collect a random urine specimen (early morning preferred).

2. No preservative.


Useful For

Screening patients suspected of having a lysosomal disorder

Genetics Test Information

This is a general urine screening test for a broad array of lysosomal and related disorders (LD). Not all LD are detectable by this method.

Disease States

  • Sialidosis
  • Galactosialidosis

Profile Information

Test ID Reporting Name Available Separately Always Performed
CTS02 Ceramide Trihex and Sulfatide, U Yes, (Order CTSU) Yes
MPS02 Mucopolysaccharides Quant, U Yes, (Order MPSQU) Yes
OLI02 Oligosaccharide Screen, U Yes, (Order OLIGU) Yes
SAU02 Sialic Acid, Free and Total, U Yes, (Order SAU) Yes
BG721 Lysosomal Disorders Interpretation No Yes

Reporting Name

Lysosomal Disorders Scrn, U

Specimen Type

Urine

Specimen Minimum Volume

3.5 mL

Specimen Stability Information

Specimen Type Temperature Time
Urine Refrigerated (preferred) 15 days
  Frozen  90 days

Reject Due To

  All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Reference Values

Dermatan Sulfate:

≤1.00 mg/mmol creatinine

 

Heparan Sulfate:

≤4 years: ≤0.50 mg/mmol creatinine

≥5 years: ≤0.25 mg/mmol creatinine

 

Chondroitin-6 Sulfate:

≤24 months: ≤10.00 mg/mmol creatinine

25 months-10 years: ≤2.50 mg/mmol creatinine

≥11 years: ≤1.50 mg/mmol creatinine

 

Keratan Sulfate:

≤12 months: ≤2.00 mg/mmol creatinine

13-24 months: ≤1.50 mg/mmol creatinine

25 months-4 years: ≤1.00 mg/mmol creatinine

5-18 years: ≤0.50 mg/mmol creatinine

≥19 years: ≤0.30 mg/mmol creatinine

 

Free Sialic Acid:

≤4 weeks: ≤208 mmol/mol creatinine

5 weeks-12 months: ≤104 mmol/mol creatinine

13 months-18 years: ≤100 mmol/mol creatinine

≥19 years: ≤38 mmol/mol creatinine

 

Total Sialic Acid:

≤4 weeks: ≤852 mmol/mol creatinine

5 weeks-12 months: ≤656 mmol/mol creatinine

13 months-18 years: ≤335 mmol/mol creatinine

≥19 years: ≤262 mmol/mol creatinine

 

Total/Free Ratio:

≤4 weeks: 1.94-18.68

5 weeks-12 months: 2.34-13.85

13 months-18 years: 2.63-9.18

≥19 years: 3.35-15.81

 

Ceramide Trihexosides:

Negative

 

Sulfatides:

Negative

 

Oligosaccharides:

Negative

An interpretive report will be provided.

Method Description

Ceramide trihexosides and sulfatides are determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis. Urine specimens are centrifuged, and most of the supernatant is discarded from the pellet. Reagent including internal standards is added, and then ceramide trihexosides and sulfatides are extracted. After centrifugation, the bottom layer is spotted onto a MALDI plate, matrix is added and allowed to air dry. The plate is then analyzed using a MALDI TOF/TOF 5800 Analyzer.(Unpublished Mayo method)

 

Dermatan sulfate (DS), heparan sulfate (HS), keratan sulfate (KS) and chondroitin-6-sulfate (C6S) are enzymatically digested from urine. The reaction mixture is centrifuged and analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). The ratio of the extracted peak area of DS, HS, KS and C6S to internal standard as determined by LC-MS/MS is used to calculate the concentration of DS, HS, KS and C6S in the sample.(Unpublished Mayo method)

 

Oligosaccharides in urine samples are extracted using Oasis HLB and carbograph columns and lyophilized overnight. Oligosaccharides are permethylated, the tubes centrifuged, and the supernatant removed. The supernatant is quenched with water, neutralized with acetic acid, extracted, eluted, and again lyophilized overnight. Specimens are resuspended, mixed 1:1 with a matrix solution, spotted onto a MALDI plate and allowed to air dry. The plate is then analyzed using a MALDI TOF/TOF 5800 Analyzer.(Xia B, Asif G, Arthur L, et al. Oligosaccharide analysis in urine by MALDI-TOF mass spectrometry for the diagnosis of lysosomal storage diseases. Clin Chem 2013;59[9]:1357-1368, Hall PL, Lam C, Alexander JJ. Urine oligosaccharide screening by MALDI-TOF for the identification of NGLY1 deficiency. Mol Genet Metab. 2018;124[1]:82-86)

 

Sialic acid in urine samples is measured twice to obtain free sialic acid and total sialic acid values. Free sialic acid is dried down and butylated in 3M hydrochloric acid in butanol. Total sialic acid is hydrolyzed with hydrochloric acid and butylated in 3M hydrochloric acid in butanol. Both samples are reconstituted in eluent and analyzed by LC-MS/MS. The free and total sialic acid samples are quantitated using an internal standard calibration curve.(Tebani A, Schlemmer D, Imbard A, et al. Measurement of free and total sialic acid by isotopic dilution liquid chromatography tandem mass spectrometry method. J. Chromatogr. B Analyt Technol Biomed Life Sci. 2011;879[31]:3694-3699, Li J, Wu T, Zhang X, et al. Clinical application of liver diseases diagnosis using ultrahigh-sensitive liquid chromatography-mass spectrometry for sialic acids detection. J. Chromatogr. A. 2022;1666:462837)

Day(s) Performed

Varies

Report Available

8 to 14 days

Specimen Retention Time

1 month

Performing Laboratory

Mayo Clinic Laboratories in Rochester

CPT Code Information

83789

83864

84377

84275

LOINC Code Information

Test ID Test Order Name Order LOINC Value
LSDS Lysosomal Disorders Scrn, U 105125-9

 

Result ID Test Result Name Result LOINC Value
621077 Dermatan Sulfate 94692-1
621078 Heparan Sulfate 94693-9
621079 Chondroitin-6 Sulfate 94690-5
621080 Keratan Sulfate 92806-9
621074 Free Sialic Acid In Process
621075 Total Sialic Acid In Process
621076 Total/Free Sialic Acid Ratio In Process
621081 Ceramide Trihexosides 34680-9
621082 Sulfatides 34646-0
621083 Oligosaccharides 49284-3
606773 Lysosomal Disorders Interpretation 94423-1
606772 Reviewed By 18771-6