Skip to content

Antimicrobial Susceptibility Test for Ceftazidime (Bacterial Culture and Antimicrobial Susceptibility)

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

This test checks whether bacteria grown from your sample are resistant or sensitive to the antibiotic ceftazidime, used to treat serious bacterial infections.

Quick summary

["Determines if your bacteria respond to ceftazidime treatment."]

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

Key facts at a glance

LOINC
101482-8
Short code
CAZ/CLA BC MIC
Synonyms
cefTAZidime+Clav Bld Pos MIC.VOC det
Category
chemistry
Sample
whole-blood
Container
Aerobic and anaerobic blood culture bottles (e.g., BACTEC, BacT/ALERT) — testing performed directly from positive blood culture broth
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
0–120 years
Method
mic-voc-detection
CPT
87181
SNOMED
104377007
Specimen volume
8-10 mL per blood culture bottle for adults; 1-3 mL for pediatric bottles; testing requires positive growth signal from blood culture system
Stability
Blood culture bottles should be incubated as soon as possible after collection; positive cultures should be processed for susceptibility testing immediately upon flagging positive (within 8 hours of positivity)
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
12–48 hours
Order
routine

What This Test Measures

This test involves growing bacteria from your sample (likely blood or other bodily fluid) and testing their response to ceftazidime. The result helps doctors choose the best antibiotic to treat your infection.

Why It’s Done

Doctors order this test when you have a suspected serious bacterial infection and need to confirm which antibiotic will work best against the bacteria causing it.

Your sample (e.g., blood, urine, or other fluid) is sent to a lab where bacteria are cultured. Once grown, they are exposed to ceftazidime, and their growth is observed to determine susceptibility.

The test uses a qualitative method to detect whether bacteria survive or grow in the presence of ceftazidime, indicating resistance or sensitivity.

Results are typically reported as 'resistant,' 'intermediate,' or 'sensitive.' Resistance means the bacteria do not respond to ceftazidime, while sensitivity means it will likely work.

A 'resistant' result may require a different antibiotic, while 'sensitive' results support using ceftazidime for treatment.

Reference range

Interpretive categories per CLSI breakpoints: Susceptible (S), Intermediate (I), Susceptible-Dose Dependent (SDD), or Resistant (R). MIC values are reported in μg/mL with corresponding interpretive criteria.N/A

Specimen: whole-blood

No special patient preparation required. Blood culture collection should be performed prior to initiation of antibiotic therapy when possible. Standard aseptic technique must be followed during venipuncture.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

This test is critical for guiding antibiotic therapy, reducing unnecessary use of broad-spectrum antibiotics, and preventing antibiotic resistance. Accurate results help ensure effective treatment and minimize harm from ineffective medications.

Short name

Ceftazidime Susceptibility Test

Frequently asked questions

What does a positive or negative result mean?
This test does not directly indicate whether you have an infection or if the bacteria are harmful. It only tells doctors how your bacteria respond to ceftazidime. A negative result (sensitive) suggests ceftazidime may treat your infection, while a positive result (resistant) means another antibiotic may be needed.
How long will I need to wait for results?
Results can take several days to a week, depending on the lab and the complexity of the culture process. Your doctor will contact you once they are available.
The process involves drawing a small sample (e.g., blood draw) and sending it to the lab for bacterial culture. There may be mild discomfort or bruising at the site, but no significant pain.
Yes, but inform your doctor if you have taken antibiotics recently. Taking antibiotics before testing may affect the accuracy of the results by altering the bacterial culture.
  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