Sign in →

Test ID: CCOC Coccidioides Antibody, Spinal Fluid

Reporting Name

Cocci CF and ID, CSF

Useful For

Diagnosing coccidioidomycosis from spinal fluid specimens


Diagnosing meningitis from spinal fluid specimens

Clinical Information

Coccidioidomycosis (valley fever, San Joaquin Valley fever) is a fungal infection found in the southwestern United States, Central America, and South America. It is acquired by inhalation of arthroconidia of Coccidioides immitis. Usually, it is a mild, self-limiting pulmonary infection, often leaving a coin-like lesion. Less commonly, chronic pneumonia may persist or progress to fibronodular cavitary disease. A rash often develops within 1 to 2 days, followed by erythema nodosum or multiforme and accompanying arthralgias. About 2 weeks after exposure, symptomatic patients develop fever, cough, malaise, and anorexia; chest pain is often severe. Coccidioidomycosis may disseminate beyond the lungs to involve multiple organs including the meninges.


Serologic testing for coccidioidomycosis should be considered when patients exhibit symptoms of meningeal infection and have lived or traveled in areas where Coccidioides immitis is endemic. Any history of exposure to the organism or travel cannot be overemphasized when coccidioidomycosis serologic tests are being considered.


Complement Fixation (CF):

IgG antibody is detected by CF testing. Any CF titer in cerebrospinal fluid (CSF) should be considered significant. A positive complement fixation test in unconcentrated CSF is diagnostic of meningitis.


Immunodiffusion (ID):

IgM and IgG precipitins are rarely found in CSF. However, when present, they are diagnostic of meningitis (100% specific). Since the ID test is 100% specific, it is helpful in interpreting CF results.


Early primary antibody (IgM) found in coccidioidomycosis can be detected by the IgM-specific ID test. IgM precipitins may be detectable within 1 to 4 weeks after the onset of symptoms. The presence of IgG antibody parallels the CF antibody and indicates an active or a recent asymptomatic infection with Coccidioides immitis. Both IgG and IgM antibodies are rarely detected 6 months after infection. However, in some patients having disseminated infection, both IgG and IgM antibodies may be present for several years. IgM and IgG precipitins are not prognostic.


An equivocal result (a band of nonidentity) cannot be interpreted as significant for a specific diagnosis. However, this may be an indication that a patient should be followed serologically.


The sensitivity of serologic testing (CF and ID combined) for coccidioidomycosis is >90% or primary symptomatic cases.

Testing Algorithm

See Meningitis/Encephalitis Panel Algorithm in Special Instructions.

Analytic Time

3 days

Day(s) and Time(s) Performed

Monday; 6 a.m.

Tuesday through Friday; 9:30 a.m.

Clinical Reference

Larone D, Mitchell T, Walsh T: Histoplasma, blastomyces, coccidioides, and other dimorphic fungi causing systemic mycoses. In Manual of Clinical Microbiology. Seventh edition. Edited by PR Murray, EJ Baron, MA Pfaller, et al: Washington, DC, ASM Press, 1999, pp 1260-1261

Method Name

Complement Fixation (CF) Using Coccidioidin: IgG
Immunodiffusion: IgG and IgM

Specimen Type


Specimen Required

Container/Tube: Sterile vial

Specimen Volume: 2 mL

Specimen Minimum Volume

1.2 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
CSF Refrigerated (preferred) 14 days
  Frozen  14 days

Reference Values



If positive, results are titered.




Results are reported as positive, negative, or equivocal.

Test Classification

This test uses a standard method. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information

86635 x 3

LOINC Code Information

Test ID Test Order Name Order LOINC Value
CCOC Cocci CF and ID, CSF 88745-5


Result ID Test Result Name Result LOINC Value
81542 Cocci Ab, CF (CSF) 13917-0
21002 Cocci ID-IgG (CSF) 94662-4
21001 Cocci ID-IgM (CSF) 94663-2


If not ordering electronically, complete, print, and send a Microbiology Test Request (T244) with the specimen.

Mayo Clinic Laboratories | Neurology Catalog Additional Information:

mml-CNS-Infections, mml-Pediatric