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pH, stool
(Not a routinely available test. See 'Additional information')

Item Value
Approval req'd? No
Available Stat? No
Test code PHF
Test group pH
Performed by Parnassus & Mission Bay Hematology
In House Availability 8:00 AM - 4:00 PM daily
Method pH strip
Collection Instructions Collect stool in plastic-lined diapers or non-absorbent material
Container type Clean container without preservative
Amount to Collect See preferred volume
Sample type Fresh loose or liquid stool
Preferred volume 10 g loose or liquid stool
Min. Volume 1/2 teaspoon loose or liquid stool
UCSF Rejection Criteria Fully formed stool. Stools collected in cotton balls, absorbent diaper, swab or kits.
Processing notes Deliver immediately to Hematology for testing. If testing is delayed freeze sample at -20C.
Units pH
Normal range > 6.5
Synonyms stool analysis; disaccharide malabsorption; stool analysis
Stability Frozen at -20C 48 hours
Turn around times Same or next day.
Additional information As normal samples are not available for validating the performance of this assay, the UCSF Clinical laboratory makes no claims with regard to the accuracy of the result.

All results will be appended with a disclaimer: "The reference range and other method performance specifications have not been established by the UCSF Clinical Laboratory for this body fluid. The test result must be integrated into the clinical context for interpretation."

Disaccharide malabsorption results in acidification of the stool from the production of short-chain fatty acids by colonic flora if antibiotics do not interfere, typically giving a pH < 5.5.

See also Reducing Substances, stool
CPT coding 83986
Last Updated 8/26/2015 1:52:38 PM
Entry Number 733
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