Skin test used for diagnosis of tuberculosis. A positive result only indicates that one has been in contact with the tubercle bacillus, but it cannot be used to know if the patient currently has infection or not.
This is a simple and rapid test that will be performed on an outpatient basis (in the doctor's office). A liquid will be injected in your arm under the skin that will leave a little bubble or "blister". You will be scheduled for another appointment days later for measurement of the “blister.” The only precaution you should have during those days will be not to scratch that area and not be rub it when washing.
Do not be frightening if the area turns red or the “blister” increases its size: This does not mean that you suffer the disease.