F. Tularensis Ab

Laboratory assay overview

This immunoassay is for the qualitative detection of antibodies (IgG, IgM) against Francisella tularensis, the causative agent of Tularemia disease. Antibodies can be detected starting 2-3 weeks after the onset of symptoms. Paired sera 2-3 weeks apart to observe seroconversion is recommended to confirm infection in patients with high clinical suspicion. This assay is intended for patients with signs and symptoms consistent with acute Tularemia and not useful for patients with resolved infection. Tularemia can cause a wide spectrum of symptoms depending on exposure. People rarely can be infected through tick and deer fly bites, contact with infected animals, drinking contaminated water, or inhalation. Antibodies against other bacteria, including Brucella, can cross-react with assays targeting Francisella. Therefore, positive serologic results should be interpreted in the context of clinical illness and exposure consistent with Tularemia infection. Antibodies can persist for years and IgM in a single sample is not a reliable indicator of recent infection. Positive IgG and IgM results can represent current, recent, or past infection since they can be detected for several years post infection. A negative result can occur early during acute infection, before the development of antibodies. References: 1. Clinical Testing and Diagnosis for Tularemia, Centers for Disease Control and Prevention. http://www.cdc.gov/tularemia/hcp/diagnosis-testing/index.html Last updated May 15, 2024. 2. Jeannine M Petersen, and Elizabeth A Dietrich, 2023. 13.4 Detection of Francisella tularensis Antibodies, Leber AL, Burnham CD Clinical Microbiology Procedures Handbook, 5th Edition. ASM Press, Washington, DC. doi: 10.1128/9781683670438.CMPH.ch13.4. 3. Maurin, Max. Francisella tularensis, Tularemia and Serological Diagnosis. Front Cell Infect Microbiol. 2020; 10:512090.

Quest Diagnostics population reference ranges

Quest Diagnostics calculates these statistical intervals for this specific assay and demographic group, not as universal optimal targets.