Stool Test Report Explained in Simple English
A stool test, also called a stool routine examination, is a laboratory test of a small sample of stool. Doctors often order it when a person has diarrhoea that lasts more than a few days, stomach pain, blood or mucus in the stool, unexplained weight loss, or suspected worm infection. The report may look confusing because it uses short medical words such as ova, cysts, pus cells, and occult blood. This guide explains each common line in plain English.
What the Report Usually Shows
Most stool reports have three parts: physical examination (what the sample looks like), chemical examination (simple chemical checks), and microscopic examination (what is seen under the microscope). Not every lab uses exactly the same words, and normal wording can vary slightly from one lab to another. Always check the reference or normal column printed beside your own result, because that column is specific to your lab.
Physical Examination: Colour and Consistency
Colour is described in simple words such as brown, yellow, green, or black. Brown is the usual colour. Yellow or green stool can occur with diarrhoea, when stool passes through the bowel quickly. Black, tar-like stool can be a sign of bleeding higher up in the digestive system, but some medicines and foods can also darken stool, so colour alone never proves bleeding.
Consistency means how solid or loose the sample is. Words such as formed, semi-formed, loose, or watery are used. Formed means a normal solid shape. Loose or watery stool usually goes with diarrhoea. A single loose sample after a stomach upset is common, but diarrhoea that lasts for days, or keeps coming back, is worth discussing with a doctor.
Mucus and Blood Seen in the Sample
Mucus is a jelly-like substance. A small amount can be normal, but a large amount of mucus, especially with pain or diarrhoea, is often noted by the lab because it can occur with inflammation or infection of the bowel.
Blood may be described as present or absent. Blood that you can see is called visible blood. Blood that cannot be seen but is found by a chemical test is called occult blood. Occult blood positive means the test found hidden blood in the sample. It does not by itself say where the blood came from. Possible causes range from piles and small cracks around the anus to inflammation or, less commonly, growths in the bowel. A positive occult blood result always needs a doctor to review it, but it is not an emergency by itself unless there are warning signs listed at the end of this guide.
Microscopic Examination: Pus Cells and Red Blood Cells
Pus cells are white blood cells seen under the microscope. A report often gives a number per high-power field, written as per HPF, which is one view under the microscope. A small number, such as 0 to 5 per HPF, is often reported as normal or insignificant. A higher number can suggest inflammation or infection in the bowel, which is why doctors pay attention to it together with fever and diarrhoea.
Red blood cells, written as RBCs, are counted in the same way. RBCs in stool can occur with bleeding from the bowel, piles, or inflammation. Like pus cells, the number matters less on its own than the full picture: how many cells, whether blood is visible, and what symptoms you have.
Ova, Cysts, and Parasites: The Worm and Germ Section
This is the section most people find hardest to read. Ova means eggs of worms. Cysts are a resting form of tiny single-celled organisms, such as Giardia or Entamoeba, that can survive outside the body and cause infection when swallowed. Parasites means the organisms themselves, such as worms or protozoa.
A normal result in this section is usually written as "No ova or cysts seen" or "No parasites seen". If the report names a specific organism, it means the lab found evidence of that infection in the sample. The name matters because different organisms are treated differently, so this section should never be guessed at. Take the report to your doctor, who will decide whether treatment is needed and which medicine, if any, is suitable. Do not take deworming medicine on the basis of a report alone without medical advice, and do not ignore a positive finding either.
It is also normal for one stool sample to miss an infection. Some organisms are not passed in every sample, so a doctor may ask for two or three samples on different days if infection is still suspected after a negative result.
Chemical Tests: Occult Blood, Reducing Substances, and pH
Occult blood, explained above, is the most common chemical test on a stool report. A negative result means no hidden blood was found in that sample. A positive result means hidden blood was found and follow-up is needed.
Reducing substances are sometimes tested in children with diarrhoea. A positive result can suggest that sugars are not being absorbed properly. This test is not on every adult report, and its meaning depends on age and symptoms, so it should be read by the doctor who ordered it.
Some reports include pH, which is a measure of acidity. Stool pH alone rarely decides anything, and it is usually only useful together with the other findings.
How to Read Your Report in Four Steps
- Read the microscopic section for ova, cysts, and parasites. "None seen" is the usual normal finding.
- Check pus cells and RBCs, and compare them with the normal range printed on your report.
- Check occult blood: negative is the usual normal result, positive needs a doctor review.
- Read the physical part for colour, consistency, mucus, and visible blood, and note whether it matches your symptoms. If every section is normal but symptoms continue for more than a few days, that is still a reason to return to your doctor, because a normal stool test does not rule out every bowel problem.
For a similar plain-English guide to a blood report, see our CBC Test Report Explainer, and to check a related risk factor, see our Diabetes Risk Checker.
When to See a Doctor Promptly
Seek medical care soon, and urgently if symptoms are severe, when you notice: blood in the stool that is heavy or ongoing; black, tar-like stool; severe stomach pain; high fever with diarrhoea; signs of dehydration such as very low urine output, extreme thirst, dizziness, or confusion; diarrhoea lasting more than three days; or weight loss without trying. Children, older adults, and pregnant women should be seen sooner for diarrhoea with blood or dehydration. This list is a guide to seeking care, not a diagnosis of any condition.
Frequently asked questions
What does no ova or cysts seen mean on a stool test report?
It means the laboratory did not find worm eggs, cysts, or parasites in that sample. It is the usual normal result for that section. It does not completely rule out infection, because some organisms are not passed in every sample, so a doctor may repeat the test if symptoms continue.
What does occult blood positive mean in a stool test?
It means a chemical test found hidden blood in the sample that cannot be seen with the eye. It does not say where the blood came from. Causes range from piles to bowel inflammation, and a doctor needs to review the full report and symptoms to decide the next step.
How many pus cells in stool are normal?
Many labs report 0 to 5 pus cells per high-power field as normal or insignificant, but the exact range printed on your own report is the one that counts. A much higher count, especially with fever or diarrhoea, can suggest bowel inflammation or infection and should be reviewed by a doctor.
What is the difference between ova and cysts on a stool report?
Ova are the eggs of worms, while cysts are a resting form of tiny single-celled organisms such as Giardia. Both are found by examining the sample under a microscope. Finding either one means the lab found evidence of a specific organism, and the named organism decides what happens next, so the report should be shown to a doctor.
Can a stool test report be normal even if I still have stomach problems?
Yes. A normal stool test rules out what it tested for in that sample, but it does not rule out every bowel problem. If diarrhoea, pain, blood, or weight loss continue after a normal report, return to your doctor for further assessment rather than assuming nothing is wrong.