Stool test: results decoding and preparation for the test
The general stool analysis is a laboratory examination of human feces in order to study its physical, chemical characteristics, composition, types of inclusions and further diagnosis of the gastrointestinal tract. All information about the interpretation of the results of stool analysis in the article is for information purposes only, do not interpret and diagnose yourself, it must be done by a specialist!
Indicator | Breastfed infants | Infants on artificial feeding | Children | Adults |
---|---|---|---|---|
Macroscopic characteristics | ||||
Quantity |
40-50 g/day |
30-40 g/day |
100-250 g/day |
10-400 g/day |
Consistency |
Viscous, puttylike |
Pasty |
Formed |
Formed |
Color |
Yellow, with shades of golden to greenish |
Light brown, orange |
Brown to dark brown |
Brown to dark brown |
Smell |
Sour, not very pungent, milky |
Sour, intensive |
Fecal, not pungent |
Fecal, not pungent |
Mucus |
A small amount of transparent mucus is acceptable |
A small amount of transparent mucus is acceptable |
Not detected |
Not detected |
Blood |
Not detected |
Not detected |
Not detected |
Not detected |
Pus |
Not detected |
Not detected |
Not detected |
Not detected |
Parasites |
Not detected |
Not detected |
Not detected |
Not detected |
Undigested food |
Not detected |
Not detected |
Small and moderate amounts of plant indigestible fiber is acceptable |
Small and moderate amounts of plant indigestible fiber is acceptable |
Chemical parameters |
|
|
|
|
Acidity, pH |
4.8–5.8 |
6.8–7.5 |
7.0–7.5 |
7.0–7.5 |
Bilirubin |
Up to three months a small amount is acceptable |
Up to three months a small amount is acceptable |
Not detected |
Not detected |
Stercobilin |
Detected |
Detected |
Detected |
Detected, 75-350 mg/day |
Soluble protein |
Not detected |
Not detected |
Not detected |
Not detected |
Microscopic characteristics |
|
|
|
|
Ammonia |
Not detected |
Not detected |
Up to 20-40 mmol/kg |
Up to 20-40 mmol/kg |
Starch |
Not detected |
Not detected |
Not detected |
Not detected |
Neutral fats |
Separate droplets are acceptable |
Acceptable in small quantities |
Not detected |
Not detected |
Fatty acids |
A small amount of crystals are acceptable |
A small amount of crystals are acceptable |
Not detected |
Not detected |
Digestible fiber |
Not detected |
Not detected |
Not detected |
Not detected |
Muscle and connective tissue fibers |
Not detected |
Not detected |
A small amount is acceptable to enter |
A small amount is acceptable to enter |
Red blood cells |
Not detected |
Not detected |
Not detected |
Not detected |
White blood cells |
Not detected or single |
Not detected or single |
Not detected or single |
Not detected or single |
Yeast-like fungi |
Not detected |
Not detected |
Not detected |
Not detected |
Iodophilic bacteria |
Not detected |
Not detected |
Not detected |
Not detected |
Epithelium cells |
Not detected or single |
Not detected or single |
Not detected or single |
Not detected or single |
Interpretation of the results of the general stool analysis
The amount of feces excreted per day directly depends on the amount of food consumed and the diet. The predominance of vegetable products on the table increases the volume of feces, while protein products decrease it. Regular deviation of the daily volume from the reference values may indicate pathology: a constant increase in the volume indicates enterocolitis, pancreatitis, cholecystitis, dyspepsia of various etiologies, increased bowel motility or IBS, a constant decrease indicates constipation or malnutrition.
Normal stool consistency in children (after weaning) and adults is cylindrical and about ¾ consisting of water. Breastfed babies normally have puttylike stools, while infants on artificial feeding have pasty stool. Biliary stone disease, cholecystitis and pancreatitis cause a smear-like consistency. Dysentery, salmonellosis, dyspepsia, and enterocolitis cause frothy stools. Hard stools are a consequence of constipation, bowel wall spasms, and stenosis of the large intestine. There are many possible causes of liquid stools, most commonly diarrhea, IBS or increased bowel motility.
The pigment stercobilin gives adult feces a characteristic brown color. In infants, the feces are lighter, toward light yellow, golden and greenish hues. In the case of infants on artificial feeding, on the contrary, the feces are usually darker, ranging from dark yellow to brown. Most often, the color of adult stools changes due to the characteristics of the diet and after taking certain medications. If, however, the rules of preparation for the stool test were followed, then here is what the change in color can indicate: black - internal bleeding, esophageal varices, peptic ulcer disease or gastric cancer; dark brown - recurrent constipation, excessive protein in the diet, problems with digestion of protein foods, colitis, dyspepsia; light brown - excess vegetable food, IBS, increased intestinal motility; reddish brown - ulcerative colitis; light yellow - pancreatitis; grayish or almost white - hepatitis, liver cirrhosis, bile duct obstruction.
Sour smell of stools is caused by fermentation processes, for children under 6 months of age sour smell is a variant of normal and is explained by the use of breast milk or artificial baby milk (in this case the smell is more intense). Putrid dyspepsia, enterocolitis, gastric pathology, ulcerative colitis and a number of more severe conditions cause putrid odor. Cholecystitis, bile duct obstruction, biliary disease, pancreatitis explain the appearance of stinky odor.
The presence of mucus, a product of destruction of the intestinal epithelium, indicates an inflammatory process in the intestine, hemorrhoids, celiac disease, cystic fibrosis or the presence of certain parasites.
Finding blood in the stool is an alarming sign. Easily detectable fresh scarlet blood in the stool most often indicates hemorrhoids or anal fissures. The combination of liquid stool and blood is a symptom of dysentery and a number of diseases of infectious nature. The appearance of streaks of blood accompanies ulcerative colitis, Crohn's disease, and less often cancer. The combination of blood cells and mucus in the tests may indicate the development of paraproctitis, colitis, polyps and intestinal diverticula. Profuse and/or regular rectal bleeding is a reason for an obligatory and immediate visit to a proctologist.
For children and adults, the detection of pus in the feces is a dangerous pathology and indicates an active inflammation in the organs of the gastrointestinal tract. In such situations, additional laboratory and instrumental examinations are always prescribed.
If a stool sample contains helminths (worms) and their eggs, antiparasitic drug therapy is prescribed.
A positive result of stool test for residual undigested food leads the doctor to assume a fermentation disorder, insufficient production of gastric juice, gastritis, or problems with intestinal motility.
A neutral acidity of feces is normal. Weak alkalinity (pH 7.5-8.0) is seen in diseases of the small intestine, medium (pH 8.0-8.5) - in pancreatitis, colitis, regular constipation, severe (pH > 8.5) - in putrefactive dyspepsia. A weakly acidic reaction is normal for infants and formula feeders due to the intake of milk and formula, while in adults increased acidity indicates an excess of carbohydrates in the diet, active fermentation processes, for example, in fermentative dyspepsia.
The body of a healthy adult completely recycles bilirubin into stercobilin. If in infants a small amount of bilirubin in the feces is considered a variant of normal and can be explained by not fully formed intestinal microflora, in adults it can indicate the development of IBS, dysbacteriosis, the recent intake of antibiotics.
A significant decrease in stercobilin in stool test results, up to its absence, indicates functional problems of the liver, cholelithiasis, and obstruction of the bile ducts. If the index exceeds the norm, then there is a suspicion of hemolytic anemia and excessive bile production.
A positive reaction to protein in the stool test usually indicates pathology of the duodenum or stomach, dyspepsia, gastritis, enterocolitis, hemorrhoids.
Even minimal concentrations of ammonia in the stools of infants are considered abnormal. For adults, however, a concentration of about 20-40 mmol/kg is acceptable. Elevated ammonia content accompanies fermentation and protein digestion disorders. Also the index increases against the background of colitis and putrefactive dyspepsia.
Starch in a healthy body is completely broken down in the gastrointestinal tract and should not be "out". Traces of intracellular starch in stools may appear in hyposecretion of gastric juice, putrefaction and fermentation processes. Extracellular starch, a product of the decay of plant cells, is not absorbed if the body does not produce enough amylase enzyme or due to an abnormally high rate of food movement through the gastrointestinal tract.
Neutral fats (triglycerides) in a stool sample may only be normal in children younger than 1 year of age. For children older and adults, non-failure to break down fats is a sign of a functional disorder of the pancreas, liver or gallbladder. Fatty acids are found in stool test results when the absorption function of the intestinal walls is impaired and intestinal motility is increased. Another cause of incomplete breakdown of fats may be a trivial overabundance of fatty foods in the diet or taking fat-containing medications.
Non-digestible fiber may be present in the stool test, it is no coincidence that it was called indigestible. But the presence of digestible fiber in the analysis, at best, indicates an overabundance of raw fruits and vegetables in the diet, at less favorable circumstances - on violations of secretory function of the stomach, bile secretion process, accelerated evacuation of stools from the intestine.
In a fully healthy body protein food (meat, fish) is completely digested. One manifestation of this process is the appearance of muscle fibers and connective tissue elements in the feces. This may be caused by insufficient production of enzymes by the pancreas and decreased acidity of the stomach.
A positive reaction for erythrocytes in a fecal analysis is usually indicative of hemorrhoids, fissures and ulcers in various parts of the intestine, and polyposis. The presence of leukocytes clearly indicates the course of an inflammatory process in one or more parts of the intestine. If an intestinal tumor disintegrates, both erythrocytes and leukocytes are found in the stool.
Yeast-like fungi proliferate against the background of dysbacteriosis caused by taking antibiotics and/or corticosteroids.
Iodophilic bacteria received their name because of their ability to change their color under the influence of iodine-containing solutions, such as Lugol solution. Pathogenic cocci and bacilli appear in the results of stool analysis in dysbacteriosis, active fermentation processes in the stomach, against a background of excessive carbohydrates in the diet, insufficient production of pancreatic enzymes.
The presence of crystals in the feces, depending on their chemical composition, may indicate processes of putrefaction, bleeding from the intestinal walls, an allergic reaction, worm infestation.
The presence of squamous epithelium cells in the feces is of no diagnostic value, cylindrical epithelium - indicates the course of acute or chronic colitis.
Preparing for a stool sample
- Stop taking antibacterials, laxatives, corticosteroids 72 hours before the scheduled time of sample collection, and do not use rectal suppositories, enemas, or pastes. It is advisable to consult a doctor about the need to stop taking certain medications.
- For 48 hours, exclude from your diet foods containing coloring substances (tomatoes, beets, blueberries, etc.), alcohol, dairy products, products that cause fermentation. Moderate consumption of fatty, spicy and pickled foods.
- It is not recommended to do a stool test during your menstrual period, as well as earlier than a week after the contrast radiography.
- Doctors recommend taking a stool sample for the study in the morning on an empty stomach, without using an enema, laxatives or other methods of stimulating peristalsis. It is better to deliver the container to the laboratory on the same day, as soon as possible. It is not recommended to keep the stool sample in the refrigerator as this can distort the results.
- No water, urine, or any other foreign liquids or chemicals should get into the stool sample. It is recommended that you urinate, then rinse your genitals and crotch thoroughly and dry with a clean towel.
- Do not defecate into the toilet to avoid contact with water, urine or chemicals. Perform defecation in a clean container or surface that does not absorb moisture: in a pot, vessel, on a plastic sheet, plastic sheet, special plastic container, etc.
- The stool sample is taken with a special spoon, which is usually included in the set of disposable sterile containers from the pharmacy. A stool sample weighing 1-2 grams should fill approximately one third of the container. It is not permitted to transport the stool sample in matchboxes and other household containers not intended for this purpose.
- Preparing for the fecal occult blood test you should exclude from your diet 72 hours before taking the sample foods with high iron, bromine and iodine content (apples, sweet peppers, beans, almonds, peanuts, seaweed, etc.), meat and fish products, all green and red vegetable products.
- For better tracking of the dynamics, it is recommended to perform a stool test in the same laboratory.