Listeria Antibody, CF, Serum

Antibodies to listeriolysin O have not provied useful for acute diagnosis of invassive disease. However, serodiagnosis of listeriosis employing measurement of antiobodies to listeriolysin O has proved useful for identifying infected individauls with noninvasive disease (asymptomatic infections, gastroenteritis) during foodborne outbreaks. 

Test Code

Quest Code

Alias/See Also

CPT Codes

Preferred Specimen
1 mL serum

Minimum Volume
0.5 mL

Transport Temperature
Room temperature

Specimen Stability
Room temperature: 7 days
Refrigerated: 14 days
Frozen: 30 days


Complement Fixation (CF)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Set up: Tues-Sat; Report available: 2-5 days

Reference Range
<1:8 titer

Interpretive Criteria
<1:8 Antibody not detected
≥1:8 Antibody detected
Single titers of ≥1:8 are suggestive of titer listeria infection. A four-fold or greater increase in titer between acute and convalescent specimens confirms the diagnosis.

Clinical Significance

This test uses complement fixation to detect antibodies to Listeria monocytogenes in serum and may be helpful in diagnosing encephalitis caused by L monocytogenes [1]. Listeriosis is mainly diagnosed by isolation of L monocytogenes; serologic tests for listeriosis are not recommended, because of their low sensitivity and specificity [2].

Listeriosis is the third-leading cause of death from eating contaminated food. Each year in the United States, approximately 1,600 people are diagnosed with listeriosis and 260 die of the condition [2]. Infected pregnant women usually have mild flu-like symptoms. However, by crossing the placenta and infecting fetuses, Listeria can cause fetal loss or newborn death in up to a quarter of cases [2,3]. Other groups at high risk of developing serious disease secondary to Listeria infection include elderly and immunocompromised individuals.

Listeria infection is mainly diagnosed by isolation of L monocytogenes from a normally sterile site. Detecting Listeria antibodies with complement fixation in serum and/or cerebrospinal fluid may be helpful for diagnosing encephalitis caused by L monocytogenes [1]. Because of their low sensitivity and specificity, serologic tests are inadequate for diagnosing listeriosis and thus are generally not recommended [2-4].

The results of this test should be interpreted in the context of pertinent clinical history and physical examination findings.

1. Miller JM, et al. Clin Infect Dis. 2018;67(6):813-816.
2. Center for Disease Control and Prevention. Listeria (Listeriosis). Accessed January 26, 2022.
3. Wellinghausen N. Toxoplasma. In: Carroll KC, et al, eds. Manual of Clinical Microbiology. 12th ed. ASM Press; 2019.
4. Gellin BG, Broome CV. Listeriosis. JAMA. 1989;261(9):1313-1320.

Performing Laboratory
Quest Diagnostics Nichols Institute-San Juan Capistrano, CA
33608 Ortega Highway
San Juan Capistrano, CA 92675-2042

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.