Coccidioides antibody (IgG) – Serum or Plasma

Why This Test Is Done

Your healthcare provider may order this test if you live in or have traveled to an area with high risk for *Coccidioides* exposure, such as parts of the southwestern U.S., Mexico, or certain regions of South America and Africa. Symptoms of infection—like fever, cough, or skin rashes—may also prompt testing. It can also be used to monitor treatment progress or assess immune response in suspected cases.

What to Expect Before the Test

No special preparation is needed. You’ll provide a blood sample (serum or plasma) via venipuncture. If you’re taking blood from your arm, you may feel a brief pinch or slight discomfort. If you have a hard time giving blood, let your provider know.

What the Test Results Mean

Positive results indicate the presence of antibodies, suggesting past or ongoing exposure to *Coccidioides*. However, antibodies alone don’t confirm active infection without clinical symptoms or additional testing. False positives can occur in rare cases. Results are used alongside symptoms, medical history, and other tests to guide diagnosis.

Possible Results and Next Steps

If results are positive, your provider may recommend further evaluation, such as chest X-rays, CT scans, or additional antibody tests (e.g., IgA or IgM) to determine if infection is active. If symptoms are mild or no longer present, follow-up may focus on monitoring rather than treatment.