Semi-Quantitative Complement Fixation
This test is New York DOH approved.
- Patient Preparation
- Serum separator tube OR CSF.
- Specimen Preparation
- Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum OR CSF to an ARUP Standard Transport Tube. (Min: 0.15 mL) Parallel testing is preferred and convalescent specimens must be received within 30 days from receipt of acute specimens. Mark specimens plainly as acute or convalescent.
- Storage/Transport Temperature
- Unacceptable Conditions
- Contaminated or severely lipemic specimens.
- After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)
Any titer suggests past or current infection. However, greater than 30 percent of cases with chronic residual pulmonary disease have negative Complement Fixation (CF) tests. Titers of less than 1:32 (even as low as 1:2) may indicate past infection or self-limited disease; titers greater than or equal to 1:32 may indicate disseminated infection. CF serology may be used to follow therapy. Antibody in CSF is considered diagnostic for coccidioidal meningitis, although 10 percent of patients with coccidioidal meningitis will not have antibody in CSF.
CF measures both IgM and IgG. As single antibody titers are generally not diagnostic, paired specimens are preferred. Acute and convalescent specimens (drawn at least 21 days apart), showing at least a fourfold rise in titer, are diagnostic.
Negative fungal serology does not rule out the possibility of current infection.
|Component Test Code*||Component Chart Name|
|0050170||Coccidioides Antibody by CF|
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, contact interface support at email@example.com.
- Cocci IgG, IgM CF
- Coccidioidomycosis IgG/IgM
- San Joaquin Fever Antibody
- Valley Fever antibodies