Coccidioides is a fungus that causes coccidioidomycosis. Coccidioidomycosis is common in the San Joaquin Valley of California and certain other areas in the southwestern U.S. Symptoms resemble pneumonia or pulmonary tuberculosis. There may be small, red, inflamed areas on the skin. This test detects exposure to this fungus.

Coccidioidin and spherulin are two different antigens and are both used to test for coccidioidomycosis. Spherulin may be a more sensitive test than coccidioidin.

• Infant test or procedure preparation (birth to 1 year)
• Toddler test or procedure preparation (1 to 3 years)
• Preschooler test or procedure preparation (3 to 6 years)
• Schoolage test or procedure preparation (6 to 12 years)
• Adolescent test or procedure preparation (12 to 18 years)

A positive reaction indicates there has been exposure to the microorganism. This test can be very helpful in diagnosing early infection, since the skin test can be positive 2 to 21 days after the onset of symptoms, even before serology is positive. A significant number of patients will have anergy, or will not respond to this test even when they have the disease.

There can be false-positives, in that there can be positive results when the patient has been exposed to histoplasma fungus or blastomyces fungus, but not coccidioides.