Electrolytes, Feces

Last Modified: 7/18/2019 12:47:07 PM

Specimen Requirements: 10.0 mL random liquid Feces/Stool Yellow Top Plastic Container
Collection Instructions: Submit frozen sample of liquid feces. Keep refrigerated during collection. Liquid stool is the only acceptable specimen for this test.

Minimum Volume: 2.0 mL liquid Feces
Transport & Storage: Temperature/Stability: 7 days Refrigerated
30 days Frozen  Transport
  *Sample must be shipped frozen to reduce odor during shipping and to minimize the risk of the container rupturing due to gas accumulation
Rejection Criteria: Specimens in paint cans; formed stool specimens received ambient or refrigerated
Reference Range: Reference ranges have not been established. However, Fecal Osmotic Gap in mOsm/kg can be calculated using the following equation: Fecal Osmotic Gap = 290 - 2x ([Na] + [K]). A Fecal Osmotic gap of 125 mOsm/kg or greater is indicative of osmotic diarrhea, whereas a result of 50 mOsm/kg or less indicates secretory diarrhea.
Methodology: Coulometric Titration • Flame Photometric
Clinical Significance: Electrolytes, stool, is useful in evaluating electrolyte loss in diarrhea and malabsorption states
Custom Panel: No


Turn Around Time: 2 to 3 days
Days Performed: Sunday, Monday, Tuesday, Wednesday, Thursday, Friday
Sites Performed: Quest - Chantilly
PHL Test Code: MSOT
EPIC Test Code:
Send Out Test Code: 31595
Included Tests: Chloride, Feces; Potassium, Feces; Sodium, Feces
CPT Coding: 82438, 84302, 84311

Go back to the top of the page.