Diagnostics
Stool Test and Culture
What is stool test and stool culture test?
How is a stool test performed?
Sample Collection: Instructed to use a clean, sterile container to collect a small sample of stool.
Laboratory Analysis: The stool sample is sent to a laboratory, where it undergoes various tests to assess digestive health. This may include examining the consistency, color, presence of blood, fat content, and pH level of the stool.
What are the common types of stool tests?
There are several types of stool tests available to diagnose various gastrointestinal disorders. Here are some of the most common ones:
- Faecal occult blood test (FOBT): Detects hidden blood in the stool, which may indicate gastrointestinal bleeding. It is often used for colorectal cancer screening or to investigate other digestive conditions. This test requires the collection of three separate stool samples.
- Fecal Immunochemical Test (FIT): FIT determines if any blood in the stool is related to the lower intestines.
- Fecal Fat Test: This test measures the amount of fat in the stool and helps evaluate conditions related to fat absorption, such as pancreatic insufficiency or malabsorption disorders.
- Stool Culture Test: This test aids in diagnosing bacterial infections within the gastrointestinal tract.
- Ova and Parasite Exam: This test checks for the presence of parasites or their eggs in the stool, assisting in the diagnosis of parasitic infections such as giardiasis or hookworm infection.
- Clostridium Difficile Toxin Test: This test specifically looks for the presence of toxins produced by the Clostridium difficile bacteria.
Stool Culture
A stool culture is a test where a sample of stool is examined in the lab to check for the presence of disease-causing bacteria.
During a stool culture, the laboratory staff will cultivate and grow bacteria in the stool. To do this, they will smear a sample of stool onto specialized plates containing a gel that provides an optimal environment for bacterial growth. The staff will then proceed to identify the bacteria using techniques such as dye staining, microscopic analysis, and other tests.
Common bacteria that laboratory staff may specifically look for in a stool culture include:
- Campylobacter species
- Salmonella species
- Shigella species
These bacteria are known to cause gastrointestinal infections and are important to identify for appropriate diagnosis and treatment.
When the stool culture test is conducted?
A stool culture is typically ordered when someone presents with signs and symptoms of an infection in the digestive tract. The symptoms include prolonged diarrhea lasting more than a few days and may contain blood and/or mucus, abdominal pain and cramping, nausea and vomiting, and fever.
While not everyone with these symptoms will undergo testing, a stool culture is more likely ordered in the following situations:
- Severe symptoms, dehydration, electrolyte imbalance, or other complications.
- Individuals who are very young, elderly, or have a weakened immune system. Diarrhea is a significant global health concern, particularly in children under 5 years, where it is a leading cause of death.
- Consumption of potentially contaminated food or fluids.
It is important to note that the doctor will decide whether to order a stool culture based on the individual’s clinical presentation and situation.
References
- Healthline. Stool Culture: Procedure, Risks, and Results. [Internet]. Healthline; c2021 [cited 2023 27th June]. Available from: https://www.healthline.com/health/stool-culture
- Netmeds. Stool Culture: Procedure, Risks, and Results. [Internet]. Netmeds; c2021 [cited 2023 27th June]. Available from: https://www.netmeds.com/health-library/post/stool-culture-procedure-risks-and-results.
