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Escherichia coli (E. coli) count in stool by culture and sensitivity

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

This test checks for the presence of harmful *Escherichia coli* bacteria in your stool, which can cause infections like urinary tract infections, diarrhea, or other illnesses.

Quick summary

["Identifying E. coli helps determine if an infection is present and guides treatment choices."]

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

Key facts at a glance

LOINC
44089-1
Short code
E coli O157H7 Spec Cult
Synonyms
E coli O157H7 Spec Cult
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
organism-specific-culture
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Is Done

Your healthcare provider may order this test if you have symptoms like persistent diarrhea, fever, abdominal pain, or if you’ve been exposed to someone with a known E. coli infection. It’s also used to diagnose urinary tract infections, food poisoning, or other gastrointestinal issues caused by bacterial contamination.

What to Expect During the Test

You’ll provide a fresh stool sample (usually collected in a sterile container) for lab testing. The sample is cultured to grow bacterial colonies, and antibiotics are tested to see which ones kill the bacteria effectively.

How the Results Are Interpreted

Results show whether E. coli is present and, if so, which antibiotics may work best. A positive result means you have an infection that may require antibiotics or other treatments. Negative results indicate no detectable E. coli.

Preparation and Care

No special preparation is needed, but avoid using laxatives or enemas before giving the sample. Keep the stool sample refrigerated if not tested immediately to prevent contamination.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Stool Culture for E. coli

Frequently asked questions

How long does it take to get results?
Results typically take 2–5 business days, depending on lab processing. Some urgent cases may receive preliminary results sooner.
What if my test is positive for E. coli?
A positive result means you likely have an infection. Your doctor will determine the best treatment—this could include antibiotics (if appropriate), increased fluids, or other supportive care. Follow-up may include retesting if symptoms persist.
Can I eat or drink before giving the stool sample?
Yes, you can eat and drink normally. Avoid using any stool softeners or laxatives unless instructed otherwise by your provider.
  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