Test directory: Osmotic Gap, Feces

Ordering Code 8559
Test Name Osmotic Gap, Feces
Alias Electrolyte & Osmolality Pnl, Fecal
Preferred Specimen Stool
Preferred Container Clean Container
Optimum Volume 10 mL
Collection Instructions Specimen must be watery liquid
Handling Instructions Specimen is forwarded to another lab for testing; do not share with other tests
Transport Requirements Oahu: Refrigerated
Airline: Frozen
Specimen Stability Ambient: Not Stable
Refrigerated: 7 Days
Frozen: 60 Days
Rejection Criteria Formed stool, Specimens in paint cans
Avail. Stat NO
Analytic Time 14 Days
Methodology Flame Photometric
Reference Lab  Quest Diagnostic Lab-NI

Reference range(s)

The reference ranges listed below are valid on this date of May 22, 2026.
Component Age Male Norm Male Critical Low Male Critical High Female Norm Female Critical High Female Critical Low Units Add'l info
Fecal Osmotic Gap ALL See report.
Sodium, Feces ALL See report.
Potassium, Feces ALL See report.