Kveim test

The Kveim test is a diagnostic procedure used to help identify sarcoidosis, a condition characterized by inflamed immune cells forming granulomas. It involves injecting a small amount of tissue extract from a person with sarcoidosis into the patient's skin. If the patient has the disease, the immune system reacts, causing a small lump or hardening at the injection site within several weeks. While historically used, the test is rarely performed today due to concerns about safety and the availability of more modern, reliable tests.