Lepromin

The lepromin skin test is used to determine what type of leprosy a person has. It involves the injection of a standardized extract of inactivated leprosy-causing bacteria (Mycobacterium leprae) under the skin. It is not recommended as a primary mode of diagnosis.

Contents

1 How the test is performed 2 Normal Values 3 Risks 4 Source

How the test is performed

An extract sample of inactivated leprosy-causing bacteria is injected just under the skin, usually on the forearm, so that a small lump pushes the skin up. The lump indicates that the antigen has been injected at the correct depth. The injection site is labeled and examined 3 days and 28 days later to see if there is a reaction.

People with dermatitis or other skin irritations should have the test performed on an unaffected part of the body. If a child needs to have this test performed, it may be helpful to explain how the test will feel, and even practice or demonstrate on a doll. The more familiar the child is with what will happen and why, the less anxiety he or she will feel. When the antigen is injected, there may be a slight stinging or burning sensation. There may also be mild itching at the site of injection afterwards.

Normal Values

People who don't have leprosy will have little or no skin reaction to the antigen. Patients with some forms of leprosy (lepromatous leprosy) will also have no skin reaction to the antigen. A positive skin reaction may be seen in patients with tuberculoid and borderline tuberculoid leprosy. Patients with lepromatous leprosy will not have a positive skin reaction.

Risks

There is an extremely small risk of an allergic reaction which may include itching and rarely hives.

Source

Lepromin skin test. Medline Plus Medical Encyclopedia. Update Date: 8/15/2003. By Daniel Levy, M.D., Ph.D., Infectious Diseases, Greater Baltimore Medical Center , Baltimore, Maryland, USA. Review provided by VeriMed Healthcare Network. Text in the US Federal Government public domain.