Fat, Feces
Use
This test is useful for diagnosing fat malabsorption due to pancreatic or intestinal disorders and for monitoring the effectiveness of enzyme supplementation in certain malabsorption disorders. Excess fecal fat, known as steatorrhea, indicates malabsorption disorders such as pancreatic insufficiency or Whipple disease. Measurement of fecal fats can aid in the diagnosis of diseases like cystic fibrosis, chronic pancreatitis, neoplasia, or stone obstruction, and intestinal diseases like Whipple disease, regional enteritis, tuberculous enteritis, gluten-induced enteropathy, and malnutrition-related atrophy.
Special Instructions
For 3 days prior to and during the collection period, patients should follow a fat-controlled diet (100-150 g fat per day) and avoid laxatives, synthetic fat substitutes, and fat-blocking nutritional supplements. Use of diaper rash ointments should be discontinued, and barium studies should be delayed 48 hours before collection. Required sample is the entire 48-hour or 72-hour collection of feces.
Limitations
This test is not useful for differentiating among pancreatic diseases. Proper patient preparation is crucial, and the use of oils or substitutes can complicate interpretation. Barium and charcoal can interfere with the results. Note that the test does not distinguish between free and neutral fatty acids, which is significant when patients use treatments like orlistat.
New York Approved
Methodology
Other
Biomarkers
LOINC Codes
- 16142-2
- 30078-0
- 13363-7
- 35745-9
- 16142-2
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Stool
Volume
Entire 48-hour or 72-hour collection
Minimum Volume
5 g from a random collection
Container
Stool container
Collection Instructions
All containers must be sent together. The entire collection must contain at least 5 g of feces. For a random collection, a minimum of 5 g is required.
Patient Preparation
For 3 days prior to and during the collection period, patient should be on a fat-controlled diet. No laxatives, synthetic fat substitutes or fat-blocking supplements. Discontinue diaper rash ointments.
Storage Instructions
Patient can store sample at refrigerate temperature during collection period.
Causes for Rejection
Preservative, media, or charcoal present
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 180 days |
| Frozen | 180 days |