Tests and diagnosis

By Mayo Clinic Staff

Valley fever is difficult to diagnose solely on the basis of signs and symptoms, because they're usually vague and overlap with symptoms that occur in other illnesses. Even a chest X-ray can't distinguish valley fever from other lung diseases.

A definitive diagnosis depends on finding evidence of coccidioides organisms in tissue, blood or other body secretions. For that reason, you're likely to have one or more of the following tests:

  • Sputum smear or culture. These tests check a sample of the matter that's discharged while coughing (sputum) for the presence of coccidioides organisms.
  • Blood tests. Through a blood test, your doctor can check for antibodies against the fungus that causes valley fever.
May 27, 2015