What It Is
Helicobacter pylori (H. pylori) bacteria are a common cause of
peptic ulcers (sores in the lining of the stomach, small intestine, or esophagus).
In this test, a stool (feces) sample is used to determine if H. pylori antigens
are present in your child's gastrointestinal (GI) system. Antigens are substances
that trigger the immune system to fight infection.
Why It's Done
A doctor may request an H. pylori antigen stool test if your child has
symptoms that could indicate the presence of a peptic ulcer, such as indigestion,
abdominal pain, a full or bloated feeling, nausea, frequent belching, or vomiting.
A test also might be ordered after your child completes a course of antibiotics for
H. pylori to determine whether it eradicated the infection.
Preparation
Unlike most other lab tests, a stool sample is often collected by parents at home,
not by health care professionals at a hospital or clinic. For 2 weeks before the test,
your child may be asked to avoid certain medications such as antibiotics, antacids,
bismuth, and peptic ulcer medicines such as proton pump inhibitors (PPIs) and H2 blockers.
Procedure
The doctor or hospital laboratory usually will provide written instructions on
how to collect a stool sample. If instructions aren't provided, here are tips for
collecting a stool sample from your child:
- Be sure to wear protective gloves and wash your hands and your child's hands afterward.
- Some young kids can't always let a parent know in advance when a bowel movement
is coming. So a hat-shaped plastic lid is used to collect the stool specimen. This
catching device can be quickly placed over a toilet bowl, or under your child's bottom,
to collect the sample. Using a catching device can prevent contamination of the stool
by water and dirt. Another way to collect a stool sample is to loosely place plastic
wrap over the seat of the toilet. Then place the stool sample in a clean, sealable
container before taking it to the lab.
- Plastic wrap can also be used to line the diaper of an infant or toddler who isn't
yet using the toilet. The wrap should be placed so that urine runs into the diaper,
not the wrap. Stools shouldn't be allowed to touch the inside of disposable diapers
because the lining usually has antibacterial properties that can interfere with the
test results.
- Your child shouldn't urinate into the container. If possible, have your child
empty his or her bladder before a bowel movement.
- The stool should be collected into clean, dry plastic jars with screw-cap lids.
Your child may be asked to provide a stool sample one or more times. For best results,
the stool should be brought to the lab right away. If this isn't possible, the stool
should be refrigerated and then taken to the lab as soon as possible.
Alternatively, a doctor or nurse may collect a small stool sample by inserting
a swab into your child's rectum.
What to Expect
When the sample arrives at the laboratory, a small amount of stool is placed in
tiny vials. Specific chemicals and a color developer are added. At the end of the
test, the presence of a blue color indicates the presence of H. pylori antigens.
Getting the Results
In general, the result of the H. pylori stool test is reported in 1-4
days.
Risks
No risks are associated with collecting stool samples.
Helping Your Child
Collecting a stool sample is painless. Tell your child that collecting the stool
won't hurt, but it has to be done carefully. A child who's old enough might be able
to collect the sample alone to avoid embarrassment. Tell your child how to do this
properly. If the sample is collected by swabbing, your child may feel slight pressure
in his or her rectum during the procedure.
If You Have Questions
If you have questions about the H. pylori stool test, speak with your
doctor.
