Test ID: FXAT
Xylose Absorption Test (Child)
NY State Approved
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Profile Information
A profile is a group of laboratory tests that are ordered and performed together under a single Mayo Test ID. Profile information lists the test performed, inclusive of the test fee, when a profile is ordered and includes reporting names and individual availability.
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| FXAT1 | Total Volume | No | Yes |
| FXAT2 | Dosage | No | Yes |
| FXAT3 | Serum Xylose at 2 hours | No | Yes |
Method Name
A short description of the method used to perform the test
Quantitative Spectrophotometry
Reporting Name
A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Aliases
Lists additional common names for a test, as an aid in searching
Dxylose FORWARD
Xylose Child FORWARD
Xylose FORWARD
Specimen Type
Describes the specimen type needed for testing
Timed Serum
Urine
Specimen Required
Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
SUBMIT ALL OF THE FOLLOWING (Read ALL collection
information prior to start of test and collection of specimens.)
Serum-Required: Fasting serum and One hour specimen
Collect blood in plain, red-top tube(s), allow to clot completely
at room temperature. Separate from cells ASAP and label tube
with "Fasting serum" or "One-hour serum" as appropriate. Ship
specimens refrigerate.
Urine
Collect all urine for five hours. Measure and record the volume,
mix well and remove a 5 mL aliquot, label sample "Five-hour
urine". Ship specimen refrigerate.
REQUIRED COLLECTION INSTRUCTIONS - Read ALL
collection information prior to start of test.
* Children are defined as less than 17 years old for the purposes
of this test.
* Xylose dose must be obtained from a pharmacy, 0.5 g xylose
per kilogram of body weight up to 25g.
* Patient should fast for eight hours (4 hours min) prior to start of test.
* Patient should empty bladder prior to start of test. (do not collect)
* Prior to xylose administration, , collect fasting serum sample, label tube
clearly "Fasting Serum"
* Give xylose in water, (5 mL of water per 0.5 g of xylose up to
250 mL water). Encourage the patient to drink additional water
following xylose dose. The patient may have water as desired,
but no other food or fluids. The patient should rest in a chair or
on a bed until completion of test. Mild diarrhea is common
following xylose ingestion.
* Collect the second serum sample one hour after giving the
xylose dose. Label tube clearly "One-hour Serum".
* Immediately following xylose dose, COLLECT ALL URINE FOR THE
NEXT FIVE HOURS. Measure and record the volume, mix
well and remove a 5 mL aliquot. Label sample "Five-hour
Urine", record total volume and the xylose dose given.
NOTE: if unable to collect peds urine, testing will be ran with
disclaimer, provided both serum specimens are received.
Specimen Minimum Volume
Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Hemolysis: | Mild OK; Gross reject |
| Thawing: | Warm reject; Cold OK |
| Lipemia: | NA |
| Icterus: | NA |
| Other: | NA |
Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
| Specimen Type | Temperature | Time |
|---|---|---|
| Serum | Refrigerated (preferred) | 7 days |
| Frozen | 30 days | |
| Ambient | 4 hours | |
| Timed Serum | Refrigerated (preferred) | 7 days |
| Frozen | 30 days | |
| Ambient | 4 hours | |
| Urine | Refrigerated (preferred) | 7 days |
| Frozen | 30 days | |
| Ambient | 4 hours |
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Several drugs can interfere with test results
-Aspirin
-Atropine
-Cochicine
-Digitalis
-Indomethacin
-MAO inhibitors
-Nalidixic acid
-Neomycin
-Opium alkaloids
-Phenelzine
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Serum fasting specimen: No reference intervals for the fasting
serum: it is used as a blank when testing the one-hour specimen.
Serum xylose at 60 min:
0-5 months: 15-58 mg/dL
6 months-16 years: 20-58 mg/dL
Xylose excretion, g/5 hr:
0-16 years: depends on dose given
Xylose excretion, % dose 5 hr:
0-16 years: 16-40 %
Test Performed By: ARUP Laboratories
500 Chipeta Way
Salt Lake City, UT 84108
Day(s) and Time(s) Test Performed
Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Tuesday, Thursday
Analytic Time
Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Maximum Laboratory Time
Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Performing Laboratory Location
The location of the laboratory that performs the test
CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
84620
LOINC® Code Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the result codes returned for this test or profile.
| Result ID | Reporting Name | LOINC Code |
|---|---|---|
| Z2664 | Total Volume | In Process |
| Z2665 | Dosage | In Process |
| Z2666 | Serum Xylose 60 Minutes | In Process |
| Z2667 | Xylose Excretion, g/5 hr | In Process |
| Z2668 | Xylose Excretion, % Dose 5 hr | In Process |


