CPT® Code 86668

The CPT® Code 86668 refers to a laboratory test specifically designed to measure antibodies against Francisella tularensis, the bacterium responsible for tularemia. This test is crucial for diagnosing infections caused by F. tularensis, which is prevalent throughout the continental United States and can affect both humans and animals. The bacterium can be transmitted through various routes, including bites from ticks and deer flies, direct skin contact with infected animals, ingestion of contaminated water, inhalation of contaminated dust, or exposure in laboratory settings. Symptoms of tularemia can manifest in several ways, including the development of skin ulcers, swollen lymph nodes, sore throat, mouth sores resulting from oral contact, and pneumonia associated with inhalation of the bacteria. The test measures two types of antibodies: IgG and IgM. Elevated levels of IgG antibodies may suggest either a current or past infection, while increased IgM levels are more indicative of a recent or ongoing infection. To perform this test, a blood sample is collected, typically through a venipuncture, which is a separately reportable procedure. The serum or plasma obtained from the blood sample is then analyzed using a semi-quantitative enzyme-linked immunosorbent assay (ELISA) method. It is important to note that there may be cross-reactivity with antibodies from other infections, such as those caused by Brucella, Yersinia, and Proteus OX19, which can complicate the interpretation of results.