Urine culture and sensitivity Lab Test

Urine culture and sensitivity

Clinical Definition of Urine culture and sensitivity

The urine culture test is performed to grow and identify organisms, mainly bacteria and fungi that may cause a Urinary Tract Infection (UTI). While in the bladder, urine is normally sterile and free from any organisms. Urinary tract infections are common in females and children than in adult males.

The antibiotic sensitivity or susceptibility test helps to select an appropriate antibiotic that is effective against specific types of bacteria or fungi causing any infection. This test needs to be conducted as some types of bacteria or fungi are resistant to certain antibiotics and infections, and they are not cured by treatment with those antibiotics.

How Do I Prepare For Urine Culture Test?

No special preparation is required for the Urine test. You just need to make sure that you are empty stomach and filled with water. At least have 3-4 glasses of water 10 mins before the test. Make sure that the urine sample collected is the mid-stream urine sample and not the one from the beginning or ending to get proper results.

Why Do I Need Urine Culture Test?

A urine Culture test is usually suggested by a doctor, when you’ve experienced pain during urinating, less urine and also frequent urine symptoms. When this is prolonged for some time (maybe 3-4 days) and if the symptoms do not subside, the doctor would then suggest a Urine Culture and Sensitivity test to determine if there is an infection and to what extent. In many cases, if the urine infection levels have increased, the person may also experience high fever and sudden chills in the body. This may go up to 5-6 days as well, if not detected and cured on time.

Urine culture and sensitivity is used to diagnose, and screen for diseases or medical conditions related to urinary tract infection for persons experiencing symptoms such as frequent and painful urination.

Reason to take Urine culture and sensitivity Test

General symptoms of a Urinary Tract Infection:-

• Painful or difficult urination with burning sensation

• Increased urination frequency 

• Urine that smells bad or appears cloudy or reddish

• Pain and pressure in the Lower abdomen (belly) and back

• Feeling Chills

• Unexpected fever

• Malaise 

• Tiredness

What Other Tests Might I Have Along With Urine Culture Test?

In the first instance, a doctor would not ask for a Urine Culture report directly. When a person reports to a doctor with Urine Sensitivity problems, the first thing the doctor would ask to do is go for a Urine Routine test. Urine Routine test is a series of tests conducted on a Urine sample to find out if any medical condition or disease exists or no. That is the first stage which will tell you that there is a problem, but the Urine Culture report will show what exactly is the problem and also get you closer to the solution.

What Is Urine Culture Test?

A Urine Culture test is basically a test done to figure out if there any types of germs in the Urine which could lead to infection. Urine, in itself, does not carry any germs, microorganisms or bacteria; but the bacteria generally enters the Urethra from the Urinary Tract and cause the infection which is commonly known as UTI, i.e. Urinary Tract Infection

The objective of the Urine culture test is to detect if there are any fungi or bacteria in the Urinary tract and provide suggestive medications to stop the growth on an immediate basis.

How Is Urine Culture Test Done?

The Urine Culture and Sensitivity test is done by collecting the Urine Sample in a clean sterilized hygienic bottle; preferably empty stomach early in the morning. First, the Urine Routine results are declared post 14-16 hours of the test being conducted. For the Urine Culture report, one has to wait for 48 – 72 hours for the report to be declared.

The Urine Sample is kept in the Laboratory for 2-3 days, and a lab worker will keep a close check on it. They would make a note of how many types of germs or bacteria are present in the urine sample and how many are growing. The test is termed Negative if there are no germs noticed in the urine sample. If there is an indication of some germs growing, then that is a clear indication that the person has a UTI. E-Coli bacteria are the most common bacteria that cause UTI.

Post detection of the bacteria, they would then analyse further to check the urine sensitivity test, which means finding the antibiotics that can affect in this situation and cure the infection completely.

Does Urine Culture Test Pose Any Risk?

No, The Urine Culture and Sensitivity test is not at all risky. It just helps us get to the root of the problem and solve it.

What Might Affect My Test Results?

Complete care is to be taken while collecting the Urine Sample to ensure that the urine has no contact with the human skin or hands or any other such source, which could dilute the test completely. Even if the container in which the sample is collected, is not sterilised or clean, it may ruin the report completely.

Sample Required?

Specimen type: Urine, Specimen collection procedure :

Mid-Stream Urine (not at the beginning and not at the end) should be collected. Ensure proper care to clean the genitals before collection.

Follow these steps to get the sample

• Initial or the first few drops of the urine should be discarded in the toilet.

• Mid-stream urine sample should be collected in the sterile container provided.

• Latter part or the end of the urine should not be collected.

• Cap the container. Keep it in the refrigerator or a cool place during the collection period.

No special preparation required.

Do not urinate for at least one hour before the test and drink a glass of water 15-20 minutes before sample collection.

What Do My Test Results Mean?

If the Urine Culture test denotes “Positive”, it means that there a certain amount of bacteria or organisms that have been found in the Urine Sample and that the infection is certainly because of these bacteria. The Culture report not only detects the various types of germs present but also shows its sensitivity to various Antibiotics. Which means you can gauge from this report itself that which antibiotics would provide maximum benefit.

The urine culture normal range is between 10,000 to 1,00,000 colonies/ml, but if it shoots above 1,00,000 colonies/pm; then it means that the Urine Infection is prevalent and some corrective actions need to be taken.

Understanding results of Urine culture and sensitivity

Reference RangeInterpretation
>100,000 colonies/mlPositive
10,000-100,000 colonies/mlIndeterminate
<10,000 colonies/mlNegative

 

Inference: Urine is normally sterile. However, in the process of collecting the urine, some contamination from skin bacteria may accour. Hence upto 10,000 colonies of bacteria/ml are considered normal. Greater than 100,000 colonies/ml represents a positive urinary tract infection. For counts between 10,000 and 100,000, the culture is indeterminate.

‘*A Reference range is a set of values which helps the healthcare professional to interpret a medical test. It may vary with age, gender, and other factors. Reference ranges may also vary between labs, in value & units depending on instruments used and method of establishment of reference ranges’

 

Conclusion

Urine Culture and Sensitivity test are done when there is an observation of painful urine excretion, and this test is done to detect any micro-organisms in the body and to eradicate them.

References

  1. https://labtestsonline.org/tests/urine-culture
  2. https://medlineplus.gov/ency/article/003741.htm
  3. https://labtestsonline.org/tests/urine-culture
  4. https://labtestsonline.org/tests/urine-culture
  5. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3106168/
  6. http://www.uofmhealth.org/health-library/hw5973