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- Fri Jul 09, 2010 9:55 am
My 72 hour fecal fat test came out high at 11.9 g/24 hours. I had an EGD and biopsy that ruled out malabsorption. Also, CBC and liver functions were normal. However no further tests were ordered. The doctor suggested if the EGD came back normal he would order an MRI of the pancreas to check for gallstones. But in the end he decided it wasn't needed. He did not order any tests of the pancreas. Should I get other tests done? My symptoms are smelly/floating stools. I also have general lack of energy.
| Dr.M.Aroon kamath
- Wed Jul 21, 2010 1:00 am
Your history suggests steatorrhea(excessive fats in stool). There is a general perception among the public that floating stools(feces) always indicate steatorrhea. However,there are a number of causes of floating stools.Kindly refer to the following link for some additional information.
For the 72 hour stool fat test to be worthwhile, the process of collection of the specimen has to be very strictly followed.
This test measures fecal fat in stool.This is a sensitive way to determine if the patient has fat malabsorption but the test does not differentiate between pancreatic and intestinal causes.
One sample protocol for stool collection is as follows:
A high fat diet is consumed by the person to be tested - with about the same amount of fat each day (100 grams fat per day) – for 5 days at a stretch. Stool collection begins the morning of the third day and continues for the next two days. Collection ends at same time as of day as start time (72 hours total collection time). The container is supplied by most laboratories.
It is very important that this diet is strictly followed. A sample Diet Plan(daily menu) is usually provided by the laboratory.
The stool passed directly into the specimen container.
Urine or water should not be allowed to come in contact with the specimen.
The samples should be refrigerated during the 72hour
collection period.Refrigeration is to prevent any bacterial action. The lab containers should never be filled more than half full. When the container is half full, a second container should be used. At the end of collection period, the completed container is finally kept in the freezer.
Normal absorption of fat is indicated by a fecal fat level of less than or equal to 7 grams per day.
D-xylose absorption test:
D-xylose is a sugar that is not normally pressent in the blood. If administered, It gets easily absorbed by healthy intestinal cells without the aid of pancreatic enzymes, and is poorly metabolized such that at least 50% of the given dose is excreted in the urine within 24 hours. This test is a good general screen for malfunction of absorption, and helps to differentiate intestinal malabsorption syndromes (reduced Dxylose absorption) from chronic pancreatitis (normal D-xylose absorption).
Gall stone disease per-se(as long as it has not affected the pancreas), is not expected to cause steatorrhea.
After intestinal malabsorbtion and chronic pancreatitis are reasonably excluded, one may start investigating for obscure causes. For a little more details on this aspect, please refer to the following link.
You may discuss your concerns and the available options with your doctor and take a collective decision.