Quantitative Fecal Fat and Alpha-1-Antitrypsin Clearance Testing—Timed Specimens (24, 48, and 72 Hours)

Collection and transport kits are available for quantitative fecal fat and alpha-1-antitrypsin clearance testing. These kits include an instructional brochure and all materials necessary for a 24-hour collection. For the 48-hour and 72-hour collections, additional containers (at least one per 24-hour period) should be supplied to the patient in addition to the collection kit).

Patient Instructions

Eat a normal diet containing 50–150 grams of fat per day for at least three days prior to beginning fecal collection. This diet should be maintained throughout the collection period. Ideally, no medications should be taken immediately prior to or during the collection period. Substances like charcoal digestion marker, castor oil, and mineral oil should be excluded from the diet prior to and during the collection.

Lab Instructions

  1. Provide the patient a timed stool collection kit (ARUP supply #44192) and additional containers (ARUP supply #28077) if a 48- or 72-hour collection is requested. Additional containers may be used as needed. The brochure in the collection kit includes patient instructions.
  2. Instruct patient to return the fecal collection to the laboratory in the provided containers.
  3. Specimen should be stored refrigerated during the collection.
  4. These approved containers of less than 500 grams per container are acceptable for transport and can be submitted without further manipulation by the receiving laboratory. All containers used in the collection must be submitted together. Each individual container must be appropriately labeled and must be further noted as one of three, two of three, etc.
  5. Order the appropriate test based upon collection period:
    • 2002354: Fat, Fecal, Quantitative, 24-Hour Collection (Includes Homogenization)
    • 2002355: Fat, Fecal, Quantitative, 48-Hour Collection (Includes Homogenization)
    • 2002356: Fat, Fecal, Quantitative, 72-Hour Collection (Includes Homogenization)
    • 2011043: Alpha-1-Antitrypsin Clearance, Quantitative by ELISA, Timed Stool
  6. Alternatively, if approved collection/transport containers are not used, collections with a total weight of less than 500 grams must be processed by the receiving laboratory as described below, and a 20 gram aliquot should be submitted. Transport of specimens weighing more than 500 grams per container is unacceptable.
  7. Laboratory aliquot preparation for timed stool collection for quantitative fecal fat testing:
    • Weigh the entire stool specimen and record the total weight.
    • Transfer the entire collection to a blending container.
    • Write patient name legibly on specimen container. Using a graduated cylinder, add sufficient water to reach milkshake consistency. The amount of water added will depend on the consistency of the specimen. This usually requires a water-to-feces ratio of one-to-one. Do not add water to a liquid specimen.
    • Record the amount of water added, blending feces and water until completely mixed.
    • Pour a 20 gram (20 mL) aliquot into a plastic leakproof sealable container and transport frozen. Minimum: 10 grams (10 mL). Use ARUP supply #040910, unpreserved stool vial. Do not send the entire stool collection.
    • Order the following test when aliquot is prepared in the receiving laboratory prior to transport to ARUP: 2002350: Fat, Fecal, Quantitative, Homogenized Aliquot.
    • Record the total weight of the collection, the amount of water added, and the length of the collection period in both the test order and on the aliquot container. This is required information.

CORP-APPEND-0249H, Rev 4, March 2015