Wound Swab for AFB Smear/ZN Stain

Specimen Required

WOUND SWAB

Fasting Required

Purpose of the Test

The test is usually performed when a person has a wound that is not healing or is showing signs of infection, and tuberculosis or other acid-fast bacilli are suspected.

When this test is required

The test may be requested by a healthcare provider when a person has a wound that is not healing or is showing signs of infection, and tuberculosis or other acid-fast bacilli are suspected. The test may also be ordered if a person has symptoms of tuberculosis, such as coughing, fever, and weight loss. It may also be ordered if a person has been in close contact with someone who has tuberculosis or if they have a weakened immune system and are at a higher risk of developing the disease.

What the Test Detects

The Wound Swab for AFB Smear/ZN Stain is a test used to detect the presence of Mycobacterium tuberculosis or other acid-fast bacilli in a wound sample. The test identifies the bacteria by staining them with a special dye called Ziehl-Neelsen (ZN) stain. Acid-fast bacteria resist being decolorized by acid alcohol, which helps distinguish them from other types of bacteria.

Preparation for the Test

No special preparation is needed for the test. However, it is important to inform the healthcare provider of any medications being taken, as some may interfere with the test results. It is also important to inform the healthcare provider of any allergies or sensitivities to medications or other substances.

Sample Requirements

The sample required is a swab taken from the wound site. The swab should be placed in a sterile container and sent to the laboratory for testing.

Additional Notes

It is important to follow proper wound care procedures when collecting the swab to avoid contaminating the sample with other bacteria. It is also important to inform the healthcare provider of any medications being taken, as some may interfere with the test results. False-negative results can occur if there are not enough bacteria present in the sample or if the bacteria are not acid-fast. Therefore, a negative result does not rule out the possibility of tuberculosis or other acid-fast bacilli infection.

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