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25443 Fat, Feces (FATF)

Fat, Feces (FATF)
Test Code: FATFSO
Synonyms/Keywords
​Fat, Feces Random
Fecal Fat
Fecal Fat, 48 hours
Fecal Fat, Quantitative
Fecal Fat, Qualitative
Fecal Fat, 72 hours
Useful For

​Diagnosing fat malabsorption due to pancreatic or intestinal disorders.

Monitoring effectiveness of enzyme supplementation in certain malabsorption disorders.

Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)		 Pediatric Minimum Volume
(no repeat)​​
​No ​ ​Entire 48 or 72 hour collection ​Mayo fecal Fat collection container(s) (supply T291) ​24 hour collection is acceptable ​All container(s) must be sent ​ ​
​Random collection ​Mayo fecal Fat collection container (supply T291) ​Sterile container ​5 g (do not send entire collection) ​5 g ​
Collection Processing Instructions

​For 3 days prior to collection:

 - Patient should be on fat controlled diet (100-150g per day)
 - No laxatives (particularly mineral oil and castor oil)
 - No synthetic fat substitutes (eg Olestra) or fat blocking nutritional supplements
 - No use of diaper rash ointments as they will falsely elevate test results
 - Barium interferes with test procedure; a waiting period of 48 hours before stool collection is recommended
 - The length of collection must be given in the order with the # of containers label #1, #2, etc...

Must use Mayo collection containers (supply T291) provided by Marshfield Labs.

Specimen Stability Information
Specimen Type Temperature Ti​​me
​Feces ​ ​Frozen (preferred) ​180 days
​Refrigerate ​180 days
Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrument​​ation
Mayo Medical Laboratories​ ​Monday through Friday ​1 day ​Nuclear Magnetic Resonance (NMR) Spectroscopy
Reference Lab
Mayo Clinic Laboratories
Reference Range Information
Performing Location Reference Ran​​ge
Mayo Medical Laboratories​ ​

​Timed Collection: >=18 years: 2-7 g fat/24 hours

Reference Values have not been established for patients who are less than 18 years of age.

​Random Collectiton: All ages: 0-19%
Interpretation

​Excretion of >7 grams fat/24 hours, when on a diet of 100 to 150 g of fat, is suggestive of a malabsorption defect.

Abnormal results from a random specimen should be confirmed by submission of a timed collection.

Test values for timed fecal fat collections will be reported in terms of g/24 hours; the duration of the collection may be 24, 48, 72, or 96 hours.  Test values for random fecal fat collections will be reported in terms of percent fat.

NOTE: This test is not useful for differentiating among pancreatic diseases.

Outreach CPTs
CPT Modifier
(if needed)		 Quantity Description Comme​​nts
82710​ ​ ​1 ​ ​
Synonyms/Keywords
​Fat, Feces Random
Fecal Fat
Fecal Fat, 48 hours
Fecal Fat, Quantitative
Fecal Fat, Qualitative
Fecal Fat, 72 hours
Ordering Applications
Ordering Application Description
If the ordering application you are looking for is not listed, contact your local laboratory for assistance.
Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)		 Pediatric Minimum Volume
(no repeat)​​
​No ​ ​Entire 48 or 72 hour collection ​Mayo fecal Fat collection container(s) (supply T291) ​24 hour collection is acceptable ​All container(s) must be sent ​ ​
​Random collection ​Mayo fecal Fat collection container (supply T291) ​Sterile container ​5 g (do not send entire collection) ​5 g ​
Collection Processing

​For 3 days prior to collection:

 - Patient should be on fat controlled diet (100-150g per day)
 - No laxatives (particularly mineral oil and castor oil)
 - No synthetic fat substitutes (eg Olestra) or fat blocking nutritional supplements
 - No use of diaper rash ointments as they will falsely elevate test results
 - Barium interferes with test procedure; a waiting period of 48 hours before stool collection is recommended
 - The length of collection must be given in the order with the # of containers label #1, #2, etc...

Must use Mayo collection containers (supply T291) provided by Marshfield Labs.

Specimen Stability Information
Specimen Type Temperature Ti​​me
​Feces ​ ​Frozen (preferred) ​180 days
​Refrigerate ​180 days
Useful For

​Diagnosing fat malabsorption due to pancreatic or intestinal disorders.

Monitoring effectiveness of enzyme supplementation in certain malabsorption disorders.

Reference Range Information
Performing Location Reference Ran​​ge
Mayo Medical Laboratories​ ​

​Timed Collection: >=18 years: 2-7 g fat/24 hours

Reference Values have not been established for patients who are less than 18 years of age.

​Random Collectiton: All ages: 0-19%
Interpretation

​Excretion of >7 grams fat/24 hours, when on a diet of 100 to 150 g of fat, is suggestive of a malabsorption defect.

Abnormal results from a random specimen should be confirmed by submission of a timed collection.

Test values for timed fecal fat collections will be reported in terms of g/24 hours; the duration of the collection may be 24, 48, 72, or 96 hours.  Test values for random fecal fat collections will be reported in terms of percent fat.

NOTE: This test is not useful for differentiating among pancreatic diseases.

For more information visit:
Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrument​​ation
Mayo Medical Laboratories​ ​Monday through Friday ​1 day ​Nuclear Magnetic Resonance (NMR) Spectroscopy
Reference Lab
Mayo Clinic Laboratories
For billing questions, see Contacts
Outreach CPTs
CPT Modifier
(if needed)		 Quantity Description Comme​​nts
82710​ ​ ​1 ​ ​
For most current information refer to the Marshfield Laboratory online reference manual.