Days Set Up
Monday, Wednesday, Friday
Analytic Time

4 - 9 days

MiChart Code
Soft Order Code

Test Updated:


Hydroxytryptamine, 5-

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Find a Requisition

All specimens should be accompanied by a requisition.

Submitting Specimens

Learn about how to properly label and where to ship specimens.

Order Kits and Supplies

MLabs provides all the supplies necessary for the collection of specimens.

Test FAQ

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Test Overview

Test Methodology

Liquid Chromatography Tandem Mass Spectrometry

Test Usage

In conjunction or as an alternative to 5-HIAA or serum chromogranin A measurements as a first line test in the diagnosis of carcinoid syndrome.

Reference Range

<=230 ng/mL

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Specimen Requirements

Collection Onsite

Collect specimen in a red top or SST tube. Deliver to Specimen Processing within 15 minutes of collection in a green bag. Specimen should be spun as soon as possible after the blood has clotted, refrigerate.

Collection Offsite

Collect specimen in a red top or SST tube. Centrifuge as soon as blood has clotted, aliquot serum into a plastic vial within 30 minutes of collection and refrigerate.

Yellow Top Tube
Normal Volume
2.5 mL serum
Minimum Volume
1.1 mL serum

Billing Information

CPT Code
Pro Fee Code

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Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.