Urine C/S (Urine Culture and Sensitivity)

Also known as Urine culture test

You need to provide

Urine

This test is for

Male, Female

Test Preparation

The urine sample must preferably be the first-morning midstream urine (part of urine that comes after the first and before the last stream). Collect the urine sample in a sealed and sterile screw-capped container provided by our sample collection professional. Ensure that the urethral area (from where the urine is passed) is clean & the container doesn't come in contact with your skin. Women are advised not to give the sample during the menstrual period unless prescribed.
If you are on any antibiotic(s), please provide clinical history, prescription, and/or specify the name of the antibiotic(s) as it may affect your test results.

Understanding Urine C/S (Urine Culture and Sensitivity)

What is Urine C/S (Urine Culture and Sensitivity)?

The Urine C/S (Urine Culture and Sensitivity) test helps detect harmful bacteria and yeast (few candida spp.) in urine that may be causing a urinary tract infection (UTI). Additionally, this sensitivity test helps identify the antibiotics most effective against those particular bacteria. It is also used to determine if there is resistance to any antibiotics.

Urine is the body’s liquid waste made when the kidneys filter out toxins from the blood. It is made up of water, salt, electrolytes such as sodium and potassium, and some metabolic end products. The pathway followed by urine from the kidneys to the outside is called the urinary tract. Sometimes, this urinary tract may get infected by some microorganisms causing a UTI.

The Urine C/S (Urine Culture and Sensitivity) test is usually done when you experience symptoms of UTI, such as a burning sensation while passing urine, back pain, painful or frequent urination, blood in the urine, etc., for appx. 3-4 days and do not subside. This test helps to identify infection-causing microorganisms. If the results are positive, the sensitivity test helps determine which drugs (or antibiotics) are likely to be most effective for treating your infection. On the other hand, a negative urine culture indicates no signs of microbial infection, hence it will not show sensitivity to various antibiotics.

Before your test, make sure to drink enough water to be able to submit a urine sample for testing. The doctor may ask you to stop taking certain medications like antibiotics and supplements before a Urine C&S test as they may affect your test results. A mid-stream urine sample should be collected into a sterile container provided by the sample collection professional. Women are advised not to give the sample during the menstrual period unless prescribed as that can interfere with certain test results.

Test result ranges are approximate and may differ slightly between different labs depending on the methodology and laboratory guidelines. Talk to your doctor about your specific test results. Narrate your complete medical history to help the doctor correlate your clinical and laboratory findings. The test results will help them determine your medical condition and formulate your overall treatment plan.

What is Urine C/S (Urine Culture and Sensitivity) used for?

The Urine C/S (Urine Culture and Sensitivity) test can be done:

If you have symptoms of UTI, such as frequent or painful urination, blood in urine, burning sensation while urinating, clouded or strong smelly urine, fever, and chills, back pain, or other urinary problems.
As part of routine medical checkups.
As part of a pregnancy checkup.

What does Urine C/S (Urine Culture and Sensitivity) measure?

The Urine C/S (Urine Culture and Sensitivity) test helps identify the bacteria or yeast (few candida spp.) causing UTI; the most common bacteria responsible for UTI is E.coli. Once the pathogen (harmful microorganism) is identified, the antibiotic susceptibility test is done to formulate a treatment plan for the infection.

Interpreting Urine C/S (Urine Culture and Sensitivity) results

Interpretations

Negative result: No colonies to less than 1,00,000 CFU/ml (Colony Forming Units)

Positive result:

· Usually more than 1,00,000 CFU/ml

· Patient undergoing antibiotic treatment: More than 1,000 CFU/ml

· For gram-positive bacteria like Staphylococcus aureus: Single colony

The negative result indicates no infection of the urinary tract.

The positive result indicates an infection of the urinary tract. An antibiotic susceptibility test accompanies the positive result.

Only a single colony type is found in an uncontaminated sample, indicating a clinically significant positive result. However, if multiple colonies of different types are found, sample contamination is indicated, and the sample may need to be collected again.

Answers to Patient Concerns & Frequently Asked Questions (FAQs) about Urine C/S (Urine Culture and Sensitivity)

Frequently Asked Questions about Urine C/S (Urine Culture and Sensitivity)

Q. What are the common UTI-causing microorganisms?

Common microorganisms that may cause a UTI are Escherichia coli (E.coli), Klebsiella spp., Proteus spp., Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus spp., Acinetobacter spp., Staphylococcus saprophyticus, and Candida spp. Sometimes a person may also get UTI due to less common organisms like Enterobacter spp, Providencia spp, Citrobacter spp, etc.

Q. What are the common symptoms of UTI?

Common symptoms of UTI include frequent urination, burning sensation while urinating, clouded or strong smelly urine, fever, and chills, back pain, blood in urine, etc.

Q. What is the difference between sensitive and resistant in urine culture?

Sensitive means the microorganism present in the urine can't grow in the presence of a particular antibiotic or the antibiotic is effective against that microorganism. Resistant means the microorganism can grow even if the antibiotic is present. This is a sign of an ineffective antibiotic. Your doctor may not prescribe this antibiotic in such a case.

Q. What is the difference between the Urine C/S (Urine Culture and Sensitivity) test and Urine Routine and Microscopy test?

The Urine C/S (Urine Culture and Sensitivity) test can identify the microorganisms responsible for UTI, whereas a urine routine and microscopy test is the examination of urine’s appearance, concentration, and content.

Q. Can the Urine C/S (Urine Culture and Sensitivity) test detect sexually transmitted diseases?

No, this test cannot detect sexually transmitted diseases.

Q. What can affect the results of the Urine C&S test?

The results of a Urine C&S test can get affected if the patient has recently taken antibiotics before the sample collection. It may also be affected if the urine sample is not collected properly. These may result in False negative or false positive results on urine culture.

Q. Can I have a negative urine culture test even with symptoms of UTI?

A negative/normal urine culture test result means that the urine sample showed no significant growth of bacteria or yeast on culture. However, if symptoms persist, a urine culture may be repeated on another sample to look for the presence of bacteria at lower colony counts. Inform the laboratory if you are already started on antibiotic therapy by your doctor, as this will affect test results. Please share your prescription if available with you.

Q. What does “mixed growth” mean in culture?

Sometimes, your culture shows several types of bacteria (mixed growth); this growth is likely due to contamination from outside your urinary tract or the surrounding skin or vaginal contamination in women in voided urine samples. If symptoms persist, your doctor may order a repeat culture on a more carefully collected “mid-stream clean catch” urine sample.

Q. Can I have WBC/ pus cells in urine routine examination, but no organism on culture?

Sterile pyuria can lead to high levels of white blood cells in urine without the presence of bacteria. It has been linked to various causes, such as recently treated UTI (usually within 2 weeks), sexually transmitted infections (STIs), cystitis, atypical infections like tuberculosis (TB), autoimmune diseases like systemic lupus erythematosus (SLE), drug intake and malignancy.

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