Fecal culture
Stool culture; Culture – stool; Gastroenteritis fecal culture
A fecal culture is a lab test to find organisms in the stool (feces) that can cause gastrointestinal symptoms and disease.
How the Test is Performed
A stool sample is needed.
There are many ways to collect the sample.
You can collect the sample:
- On plastic wrap. Place the wrap loosely over the toilet bowl so that it is held in place by the toilet seat. Put the sample in a clean container given to you by your health care provider.
- In a test kit that supplies a special toilet tissue. Put it in a clean container given to you by your provider.
Do not mix urine, water, or toilet tissue with the sample.
For children wearing diapers:
- Line the diaper with plastic wrap.
- Position the plastic wrap so that it will prevent urine and stool from mixing. This will provide a better sample.
Return the sample to the laboratory as soon as possible. Do not include toilet paper or urine in the specimen.
In the lab, a technician places a sample of the specimen in a special dish. The dish is then filled with a gel that boosts the growth of bacteria or other germs. If there is growth, the germs are identified. The lab technician may also do more tests to determine the best treatment.
How to Prepare for the Test
You will get a collection container for the stool specimen.
How the Test will Feel
There is no discomfort.
Why the Test is Performed
The test is performed when your health care provider suspects that you may have a gastrointestinal infection. It may be done if you have severe diarrhea that does not go away or that keeps coming back.
Normal Results
There are no abnormal bacteria or other organisms in the sample.
Talk to your provider about the meaning of your specific test results.
What Abnormal Results Mean
Abnormal results may mean you have an intestinal infection .
Risks
There are no risks.
Considerations
Often other stool tests are done in addition to the culture, such as:
- Gram stain of stool
- Fecal smear
- Stool ova and parasites exam
Fecal fat
Quantitative stool fat determination; Fat absorption
The fecal fat test measures the amount of fat in the stool. This can help gauge the percentage of dietary fat that the body does not absorb.
How the Test is Performed
There are many ways to collect the samples.
- For adults and children, you can catch the stool on plastic wrap that is loosely placed over the toilet bowl and held in place by the toilet seat. Then put the sample in a clean container. One test kit supplies a special toilet tissue that you use to collect the sample, then put the sample in a clean container.
- For infants and children wearing diapers, you can line the diaper with plastic wrap. If the plastic wrap is placed properly, you can prevent mixing of urine and stool. This will provide a better sample.
Collect all stool that is released over a 24-hour period (or sometimes 3 days) in the containers provided. Label the containers with name, time, and date, and send them to the lab.
How to Prepare for the Test
Eat a normal diet containing about 100 grams (g) of fat per day for 3 days before starting the test. The health care provider may ask you to stop using drugs or food additives that could affect the test.
How the Test will Feel
The test involves only normal bowel movements. There is no discomfort.
Why the Test is Performed
This test evaluates fat absorption to tell how well the liver, gallbladder, pancreas, and intestines are working.
Fat malabsorption can cause a change in your stools called steatorrhea. To absorb fat normally, the body needs bile from the gallbladder (or liver if the gallbladder has been removed), enzymes from the pancreas, and normal intestines.
Normal Results
Less than 7 g of fat per 24 hours.
What Abnormal Results Mean
Decreased fat absorption may be caused by:
- Biliary cancer
- Biliary stricture
- Celiac disease
- Chronic pancreatitis
- Crohn disease
- Cystic fibrosis
- Gallstones ( cholelithiasis )
- Pancreatic cancer
- Pancreatitis
- Radiation enteritis
- Short bowel syndrome (for example from surgery or an inherited problem)
- Sprue
- Whipple disease
- Small bowel bacterial overgrowth
Risks
There are no risks.
Considerations
Factors that interfere with the test are:
- Enemas
- Laxatives
- Mineral oil
Flushable reagent stool blood test
Stool occult blood test – flushable home test; Fecal occult blood test – flushable home test
Flushable reagent stool blood test is an at-home test to detect hidden blood in the stool.
How the Test is Performed
This test is performed at home with disposable pads. You can buy the pads at the drug store without a prescription. Brand names include EZ-Detect, HomeChek Reveal, and ColoCARE.
You do not handle stool directly with this test. You simply note any changes you see on a card and then mail the results card to your health care provider.
To do the test:
- Urinate if you need to, then flush the toilet before having a bowel movement.
- After the bowel movement, place the disposable pad in the toilet.
- Watch for a change of color on the test area of the pad. Results will appear in about 2 minutes.
- Note the results on the card provided, then flush the pad away.
- Repeat for the next two bowel movements.
The different tests use different ways to check for water quality. Check the package for instructions.
How to Prepare for the Test
Some medicines may interfere with this test.
Check with your provider about changes in your medicines you may need to make. Never stop taking a medicine or change how you take it without first talking to your provider.
Check test package to see if there are any foods you need to stop eating before doing the test.
How the Test will Feel
This test involves only normal bowel functions, and there is no discomfort.
Why the Test is Performed
This test is mainly performed for colorectal cancer screening. It may also be done in the case of low levels of red blood cells (anemia).
Normal Results
A negative result is normal.
Normal value ranges may vary slightly among different labs. Talk to your provider about your test results.
What Abnormal Results Mean
Abnormal results of the flushable pad mean there is bleeding present somewhere in the digestive tract, which may be caused by:
- Swollen, fragile blood vessels in the colon that may result in blood loss
- Colon cancer
- Colon polyps
- Enlarged veins, called varices, in the walls of the esophagus (the tube that connects your throat to your stomach) bleed
- When the lining of the stomach or the esophagus becomes inflamed or swollen
- Infections in the stomach and intestines
- Hemorrhoids
- Crohn disease or ulcerative colitis
- Ulcer in the stomach or first part of the intestines
Other causes of a positive test, which do not indicate a problem in the gastrointestinal tract, include:
- Coughing up and then swallowing blood
- Nose bleed
Abnormal test results require follow-up with your doctor.
Risks
The test can have false-positive (the test indicates a problem when there actually is none) or false-negative (the test indicates there is NOT a problem, but there is) results. This is similar to other stool smear tests which can also give false results.
Fecal smear
Stool smear
Fecal smear is a laboratory test to for a stool sample. This test is done to check for bacteria and other organisms. Presence of organisms in stool shows diseases in the digestive tract.
How the Test is Performed
A stool sample is needed.
There are many ways to collect the sample. You can collect the sample:
- On plastic wrap. Place the wrap loosely over the toilet bowl so that it is held in place by the toilet seat. Put the sample in a clean container given to you by your health care provider.
- In a test kit that supplies a special toilet tissue. Put it in a clean container given to you by your provider.
Do not mix urine, water, or toilet tissue with the sample.
For children wearing diapers:
- Line the diaper with plastic wrap.
- Position the plastic wrap so that it will prevent urine and stool from mixing. This will provide a better sample.
- Put the sample in a container given to you by your health care provider.
Make sure you follow your provider’s instructions for returning the sample. Return the sample to the lab as soon as possible.
The stool sample is sent to a lab where a small amount is placed on a slide. The slide is placed under a microscope and checked for the presence of bacteria, fungi, parasites, or viruses. A stain may be placed on the sample that highlights certain germs under the microscope.
How to Prepare for the Test
There is no preparation needed.
How the Test will Feel
There is no discomfort.
Why the Test is Performed
Your provider may order this test if you have severe diarrhea that will not go away or that keeps returning. The test result may be used to select the correct antibiotic treatment.
Normal Results
A normal result means there are no disease-causing germs present.
Normal value ranges may vary slightly among different labs. Talk to your provider about the meaning of your test results.
What Abnormal Results Mean
An abnormal result means that abnormal germs have been found in the stool sample. This may be due to an infection of the digestive tract.
Risks
There are no risks associated with a fecal smear.