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Colony Count of Stool Sample (Anaerobic Culture)

Published: August 9, 2026Updated: August 16, 2026

This test measures the number of bacteria colonies grown from a sample of your stool under strict oxygen-free conditions. It helps identify if harmful bacteria are present in your digestive system.

Quick summary

["Assessing bacterial overgrowth or infection in your gut with precision."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
64096-1
Short code
Colonies counted Amn
Synonyms
Colonies counted Amn
Category
chemistry
Sample
fluid
Container
Sterile tube
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
molgen
Specimen volume
2-5 mL
Stability
Room temperature: 2h, Refrigerated: 24h
Hemolysis max
300
TAT
4–24 hours
Order
routine

Why This Test Is Done

Your doctor may recommend this test if you have symptoms like persistent diarrhea, abdominal pain, bloating, or unexplained weight loss. It can also be used to check for infections like Clostridium difficile or other harmful bacteria that might not be caught by standard stool tests.

How the Test Works

A small sample of your stool is collected and placed in a special environment where only bacteria that thrive without oxygen (anaerobic bacteria) are allowed to grow. After several days, the number of colonies (visible bacterial growth) is counted under a microscope.

What to Expect Before the Test

No special preparation is needed, but you may be asked to avoid certain medications (like antibiotics) that could affect the results. If you have a recent infection or are on antibiotics, let your doctor know before testing.

What to Expect During the Test

The test involves collecting a stool sample, usually via a clean container provided by your healthcare provider. The sample is then sent to a lab for processing and incubation.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Stool Culture Count

Frequently asked questions

How long does it take to get results?
Results typically take 3 to 7 days, depending on the lab and whether additional testing (like antibiotic sensitivity) is needed.
What does a high or low colony count mean?
A high colony count often signals an infection or imbalance in gut bacteria, while a low count may indicate a normal bacterial presence. Your doctor will interpret results in the context of your symptoms and medical history.
Can I eat or drink before the test?
Yes, you can eat and drink normally before the test, but avoid certain medications that might affect bacterial growth unless instructed otherwise.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy