CPT® Code 86619

The CPT® Code 86619 refers to a laboratory test specifically designed to measure antibodies against Borrelia, the bacteria responsible for relapsing fever. This condition can be caused by two types of Borrelia spirochetes: those transmitted by ticks, known as tick-borne relapsing fever (TBRF), and those transmitted by lice, referred to as louse-borne relapsing fever (LBRF). TBRF is predominantly found in the western regions of the United States, particularly in mountainous areas that are infested with rodents, which serve as reservoirs for the disease. In contrast, LBRF is typically associated with refugee populations in underdeveloped regions of the world, where conditions may facilitate the spread of lice. Relapsing fever is characterized by a series of symptoms that include fever, chills, headache, muscle and joint pain, nausea, and potentially a rash. The onset of these symptoms usually occurs between 5 to 15 days following a tick or louse bite, and the symptoms can persist for a duration of 2 to 9 days. After an initial phase of symptoms, there may be a spontaneous remission, but the cycle of symptoms can recur until the patient receives appropriate antibiotic treatment. To perform this test, a blood sample is collected, which is reported separately through a venipuncture procedure. The serum obtained from the blood sample is then analyzed using a semi-quantitative immunofluorescence assay or an indirect fluorescent antibody technique, allowing for the detection of antibodies specific to Borrelia.