What is involved in a stool fat test?

Stool fat test (fecal fat quantification), also known as a fecal fat analysis, is a laboratory test that measures the amount of fat in the stool. It is used to assess the absorption and digestion of dietary fat, and to diagnose conditions such as malabsorption, celiac disease, pancreatitis, and Crohn's disease.

Procedure:

1. Collect a stool sample: You will be given a special container and instructions for collecting a stool sample. It's important to collect the sample in the container provided and follow the instructions carefully to ensure an accurate test result.

2. Send the sample to the laboratory: Once collected, the stool sample should be sent to a laboratory for analysis.

3. Laboratory analysis: At the laboratory, the stool sample will be analyzed using a variety of methods to determine the amount of fat present. Common methods include:

a) Van de Kamer method: This involves dissolving the stool sample in a chemical solvent and then separating the fat from the other components. The amount of fat is then measured.

b) Acid hydrolysis method: This involves using acid to break down the stool sample, releasing the fat. The fat is then extracted and measured.

The laboratory will provide a report with the results of the stool fat test, which will be sent to your doctor.

Preparation:

Before the test, your doctor may ask you to:

- Avoid taking certain medications that can interfere with the test results, such as mineral oil, laxatives, or antacids.

- Follow a specific diet for a period of time to ensure adequate fat intake. You may be asked to consume a high-fat diet for a few days before the test. This is to ensure that there is enough fat in the stool to be measured.

- Avoid collecting the stool sample during menstruation.

Interpretation of Results:

Abnormal stool fat levels may indicate:

- Malabsorption: Difficulty digesting and absorbing dietary fat. This can be caused by conditions such as celiac disease, Crohn's disease, pancreatitis, or infections.

- Pancreatic insufficiency: Insufficient production of pancreatic enzymes, which are necessary for digesting fat.

- Biliary tract disease: Conditions affecting the gallbladder and bile ducts, which can interfere with the digestion of fat.

- Small intestinal bacterial overgrowth (SIBO): An excessive amount of bacteria in the small intestine, which can lead to malabsorption of nutrients.

The specific interpretation of the results will depend on the patient's individual circumstances, and your doctor will discuss the results and recommend appropriate treatment if necessary.