IgM and IgG antibodies to Coccidioides antigen usually appear during the first month of infection, decline over the next 3-6 months but remain detectable for approximately 18-24 months in some cases with self-limited illnesses. Antibodies may persist in patients with chronic pulmonary complications or progressive extrapulmonary (disseminated) coccidioidomycosis. Antibodies may be falsely-negative in some progressive or chronic cases. Follow-up testing maybe considered at weeks 2 – 4 to determine if antibody levels are increasing especially in patients with low positive (10 EU – 20 EU) or intermediate results. Increase in antibody concentration would suggest recent infection. Antibodies may also be detected in healthy subjects who are asymptomatic as a result of sub-clinical infection within the last 18 – 36 months.
1.0 mL Serum from a SST Gold Top Tube
CSF: Sterile transport tube
1.0 mL Serum from a Red Top Tube in a Plastic Vial
14 days Refrigerated
14 days Frozen
Allow blood to clot for 30 minutes, then centrifuge.
Pipette serum into a plastic screw cap via
0.5 mL Serum
Negative
Negative: <1.0 EU
Positive: > 1.0 EU
Limitations:
8% cross reactivity with Blastomyosis
36% cross reactivity with Histoplasmosis
IgM and IgG antibodies to Coccidioides antigen usually appear during the first month of infection, decline over the next 3-6 months but remain detectable for approximately 18-24 months in some cases with self-limited illnesses. Antibodies may persist in patients with chronic pulmonary complications or progressive extrapulmonary (disseminated) coccidioidomycosis. Antibodies may be falsely-negative in some progressive or chronic cases. Follow-up testing maybe considered at weeks 2 – 4 to determine if antibody levels are increasing especially in patients with low positive (10 EU – 20 EU) or intermediate results. Increase in antibody concentration would suggest recent infection. Antibodies may also be detected in healthy subjects who are asymptomatic as a result of sub-clinical infection within the last 18 – 36 months.
Cross-reactions occur with Aspergillus spp., Histoplasma capsulatum, Parcocidioides brasiliensis, and Talaromyces mameffei.
1 to 2 days
00913912; 00913899
86635 x 2