Culture and Sensitivity Test, Aerobic Bacteria, Urine

• To diagnose a urinary tract infection (UTI) by identifying the presence of bacteria in the urine.
• To pinpoint the specific type of bacteria causing the UTI (aerobic bacteria in this case).
• To determine which antibiotics are most effective against the identified bacteria for targeted treatment.

This test establishes presence or absence of significant bacterial growth in urine. If significant growth is found then antibiotic susceptibility testing is also done.

This test requires a urine sample. Patient will be explained how to collect mid-stream urine sample in a sterile container.

Ideally, a urine culture should show no growth of bacteria, indicating a healthy urinary tract.

However, due to possible contamination during collection, a small amount of growth is sometimes tolerated.

Up to 10,000 colony forming units (CFU) per milliliter (mL) of urine is generally considered within the normal range for a urine culture.

• No growth/ Insignificant growth: This means that bacteria was not isolated in significant numbers in the sample.
• Significant Growth: This means that bacterium has been isolated in significant numbers thus implying it to be the causative agent of UTI. The sensitivity of the bacterium towards various antibiotics is also reported. The result have to be correlated clinically and other laboratory finding like pus cells in urine.
• Results may be false negative under the following conditions:

1. Patient is on antibiotics
2. Infection due to a fastidious or anaerobic bacterium (this test is for routine aerobic bacteria which are the causative agents of most UTI)

• Results may be false positive if contamination occurs while collecting the sample