Diagnosis

To diagnose valley fever, your doctor may evaluate your medical history and review your signs and symptoms. Valley fever is difficult to diagnose based on the signs and symptoms, because symptoms are usually vague and similar to those that occur in other illnesses. Even a chest X-ray can't help doctors see the difference between valley fever and other lung diseases.

To diagnose valley fever, doctors may order 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.

If doctors think you may have pneumonia associated with valley fever, they may also order imaging tests, such as a CT scan, MRI or chest X-ray.

If needed, doctors may remove a sample of tissue from the lungs for testing.

In some cases, doctors may do a skin test to find out if you've had valley fever in the past and have developed immunity.