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Gram Stain Bacteria Detection by Fluorescent Probe (for Blood)

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

This test uses a fluorescent probe to help identify bacteria in your blood sample, often used to guide treatment for suspected infections.

Quick summary

["A quick tool to check for potential bacterial infections in your bloodstream."]

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

Key facts at a glance

LOINC
106905-3
Short code
GN bact DNA Ct Bld Pos Qn NAA+probe
Synonyms
GN bact DNA Ct Bld Pos Qn NAA+probe
Category
chemistry
Sample
whole-blood
Container
Lavender-top (EDTA)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
probe-amp-tar
Specimen volume
3 mL
Stability
Room temperature: 4h, Refrigerated: 24h
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

What This Test Does

This test involves examining a small sample of your whole blood under a microscope with a special fluorescent dye. The probe binds to bacterial cells if they are present, making them visible under certain lighting conditions. This helps healthcare providers determine whether bacteria are likely causing an infection.

How the Test Works

The fluorescent probe targets specific components of bacteria, allowing for visual confirmation of their presence. Unlike traditional Gram staining, this method uses advanced imaging to enhance sensitivity and specificity for detecting bacteria in blood.

When You Might Need This Test

This test may be used when you have symptoms of a blood infection (sepsis), unexplained fever, or other signs of possible bacterial contamination in your bloodstream. It is often performed as part of a broader diagnostic evaluation.

What to Expect Before the Test

No special preparation is needed for this test. A healthcare provider will draw a small amount of blood, typically from your arm, and send it to the lab for analysis. The process usually takes a few minutes.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Blood Gram Stain Probe Test

Frequently asked questions

How long does it take to get results from this test?
Results are typically available within a few hours to a couple of days, depending on lab processing times. Your healthcare provider will discuss the findings with you during your follow-up visit.
Can this test detect all types of bacteria?
This test uses a fluorescent probe to detect a broad range of bacteria, but it may not identify specific bacterial species. For detailed identification, additional tests (like culture) may be needed.
Is there any risk or discomfort associated with this test?
The test involves a small needle insertion, which may cause slight discomfort or bruising at the site. Rarely, there may be mild swelling or redness. Most people tolerate the procedure well.
  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