Days Set Up
Analytic Time
MiChart Code
Reducing Substances, Stool
Soft Order Code

Test Updated:


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Test Overview

Test Methodology


Test Usage

Testing for reducing substances in stool is used in diagnosing the cause of diarrhea in children. Increased reducing substances in stool are consistent with primary or secondary disaccharidase deficiency and intestinal monosaccharide malabsorption. Similar intestinal absorption deficiencies are associated with short bowel syndrome and necrotizing enterocolitis. Stool reducing substances is also helpful in diagnosing between osmotic diarrhea caused by abnormal excretion of various sugars as opposed to diarrhea caused by viruses and parasites.

Reference Range

Negative. A result of 0.25% to 0.5% is suspicious for a carbohydrate absorption abnormality, >= 0.75% is abnormal.

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

Specimen Requirements

Collection Offsite

Collect liquid stool in a plastic urine container or screw top stool container. Refrigerate. Do not collect and dispense from disposable diaper; stool liquid (which would be absorbed in diaper) is most important part of sample. Formed stool not acceptable.

Normal Volume
10 mL liquid stool.
Minimum Volume
3 mL liquid stool.

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.