Pus (aerobic) culture test

Your doctor may order this test if you have an infection in an area of inflammation or a wound. Symptoms that indicate an infection in the wound or inflammation include:

• The affected area feels warm to touch
• Redness in the affected area
• Swelling or a lump in the affected area
• Pain
• Pus draining from the inflamed area or wound
• Bumps around the wound that look like boils or a rash

In addition to the above symptoms, severe infection is also associated with:

• Fever
• Chills
• Weakness and tiredness
• Confusion

You do not have to prepare specially for this test. Inform the doctor if you are taking any medicine, vitamins or mineral supplements.

This test requires a sample of pus or fluid from the infected area. Based on the site of infection and the amount of pus present, your doctor may use either a swab (cotton bud) or a syringe to obtain a sample. Sometimes, a tissue sample is taken from the wound for testing. Here is how the sample will be collected: 

• Your doctor will clean the area with 70% alcohol or an iodine solution and will allow it to dry. 
• If the wound is superficial, the doctor may use a swab to obtain a sample. He/she will rotate the swab several times over the clean wound surfaces to collect the pus. If the pus is minimal, the doctor will apply gentle pressure when rotating the swab to express sufficient fluid from the wound. 
• In case of deeper or closed wounds, he/she may use a syringe to aspirate a small quantity of fluid or takes a tissue sample for the test.
• In case of ulcers, the doctor may either take a tissue sample or use a needle to aspirate from the edge of the ulcer. Sometimes, he/she may irrigate the ulcer with saline (salt solution), massage the edge of the ulcer and then use a syringe to aspirate a required sample of fluid. 
• The swab or fluid collected will be immediately placed in a suitable container.
• The container will be labelled appropriately and sent to the laboratory for testing.

Results take about 7 to 14 days to show up.

This test is not associated with any risk factors or side effects. 

Normal results: 

When no aerobic bacteria grow in the culture, the results are reported as negative.

Normal results indicate that you don’t have an infection from aerobic bacteria in the affected area.

Abnormal results: 

If aerobic bacteria grow in the culture, the results are reported as positive.

Your doctor will prescribe suitable antibiotics for treating the infection on the basis of the type of bacteria obtained in the test.

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.