Test Details
Methodology
Extraction/spectrophotometry
Result Turnaround Time
4 - 7 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Test Includes
Stool weight and fat content (in g/24 hours)
Use
In malabsorption syndromes, notably pancreatic insufficiency and Whipple disease, steatorrhea is a prominent feature. Fecal fats can be useful in diagnosis of cystic fibrosis, chronic pancreatitis, neoplasia, or stone obstruction. Also useful in regional enteritis, celiac disease, sprue, and the atrophy of malnutrition.
Special Instructions
Both the container and the test request form must state collection time (in hours). Collections of 24 or 48 hours are not recommended since results are subject to greater variability. Also, please indicate the patient's age on the test request form.
Limitations
C8 and C10 saturated fatty acids are not quantitated with this method.
This test was developed, and its performance characteristics determined, by LabCorp. It has not been cleared or approved by the Food and Drug Administration.
Specimen Requirements
Specimen
Stool (72-hour)
Volume
Entire collection or 5 to 25 mL of a homogenized aliquot
Container
One or more clean LabCorp-approved stool collection kits (order LabCorp N° 03192) containing a 1-gallon can, absorbent sheet, Armlock O-ring, and a leakproof plastic bag
Collection Instructions
Collect stool directly into can. Do not fill any can more than 2/3 full. Secure lid with pressure and firmly attach the O-ring. State collection time on the can label. Place the can and the absorbent sheet into the leakproof plastic bag and seal. Send the entire can, or if submitting aliquot, follow this procedure:
1. Weigh specimen and collection container and subtract the weight of an empty container of same type (one-gallon can weight with lid: 360 g metal or 320 g plastic container). This is the “net weight” to be recorded on the test request form.
2. Open the container and observe whether the contents are liquid. If liquid stool, secure the lid, mix, and submit an aliquot of the total collection. If solid stool, add deionized water (approximately 500 mL) to the specimen container and mix thoroughly to create a homogenous specimen. Submit a 5 to 25 mL aliquot of the total collection in an empty stool transport vial (LabCorp N° 59517) or screw-cap urine bottle (LabCorp N° 20648), sterile no additives.
3. Record on both the container and the test request form the amount of water added to liquefy the stool or if no water was required.
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | 5 days |
Refrigerated | 14 days |
Frozen | 14 days |
Freeze/thaw cycles | Stable x3 |
Reference Range
• 0 to 18 years: 0.0-3.1 g/24 hours
• >18 years: 0.0−7.1 g/24 hours
Storage Instructions
Refrigerate specimen during collection and store at 2°C to 8°C.
Patient Preparation
Adult patients should be on a standard diet containing 50 to 150 g of fat per day for at least three days before test is started and during the 72-hour collection. In children, the amount of fat in the diet should be constant for one day before the test and during the test. The patient should not have had mineral oil as a laxative prior to specimen collection.
Causes for Rejection
Container more than 2/3 full; container leaking; improper container (ie, non−LabCorp-approved paint can, paper cartons, coffee cans, plastic bags, etc); foreign matter other than feces inside of container (ie, spoons, tongue depressors, plastic bags, toilet paper, etc); patient not on special diet; improper labeling of container or test request form; specimen on outside of container; specimen contaminated with urine; aliquot without “net weight” and “amount of water added” to homogenize the sample
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 001354 | Fecal Fat, Quantitative | 16142-2 | 016840 | Fecal Weight (Total) | g | 30078-0 |
| 001354 | Fecal Fat, Quantitative | 16142-2 | 016832 | Fat,(Fecal Lipids)Qn | g/24 hr | 16142-2 |
| Order Code | 001354 | |||||
| Order Code Name | Fecal Fat, Quantitative | |||||
| Order Loinc | 16142-2 | |||||
| Result Code | 016840 | |||||
| Result Code Name | Fecal Weight (Total) | |||||
| UofM | g | |||||
| Result LOINC | 30078-0 | |||||
| Order Code | 001354 | |||||
| Order Code Name | Fecal Fat, Quantitative | |||||
| Order Loinc | 16142-2 | |||||
| Result Code | 016832 | |||||
| Result Code Name | Fat,(Fecal Lipids)Qn | |||||
| UofM | g/24 hr | |||||
| Result LOINC | 16142-2 |