What test is used for valley fever?

Valley fever is typically diagnosed with one or more of the following tests:

1. Serologic tests:

- Immunodiffusion (ID) test: Detects antibodies against Coccidioides immitis in the blood. A positive ID test indicates a current or past infection.

- Complement fixation (CF) test: Measures the level of antibodies that bind to and activate complement proteins. Rising CF titers over time suggest an active infection.

- Enzyme immunoassay (EIA) and chemiluminescence immunoassay (CLIA): These tests detect antibodies specific to C. immitis.

2. Skin tests:

- Coccidioidin skin test: Involves injecting a small amount of coccidioidin, a protein derived from C. immitis, into the skin. A positive reaction, characterized by a raised, hardened area at the injection site, indicates previous exposure to the fungus.

3. Culture:

- Specimens from respiratory secretions, tissues, or body fluids are collected and incubated in a laboratory to grow C. immitis. A positive culture confirms the presence of an active infection.

4. Molecular tests:

- Polymerase chain reaction (PCR): Detects the DNA of C. immitis in clinical specimens. PCR can be used on various samples, including blood, sputum, or tissue biopsies.

The specific tests ordered by a healthcare professional may vary depending on the patient's symptoms, risk factors, and the availability of diagnostic resources. In some cases, a combination of tests may be used to establish a definitive diagnosis of Valley fever.