Gene-Finding in Coccidioides immitis

Coccidioides immitis is a primary fungal pathogen that lives in the soil of the desert Southwest. Like most medically important fungi that cause systemic disease, C. immitis exhibits different morphologies in its saprobic and parasitic phases, but is distinguished from other fungal pathogens by the unique morphogenetic features of its growth in host tissue (Fig. 1). Coccidioidomycosis, the disease caused by this pathogenic fungus, is also known as Valley Fever because the organism is prevalent in the San Joaquin Valley of Central California. C. immitis infections are caused by inhalation of the organism. The clinical spectrum of disease is broad, ranging from an asymptomatic infection to a rapidly fatal mycosis (1).The most common clinical presentation is self-limited pneumonia, but in some cases the fungus can cause chronic cavitary pulmonary disease or disseminate beyond the lungs to the skin, bones, meninges, and other body organs. It has been estimated, primarily on the basis of skin tests, that there are between 25,000 and 100,000 new cases of human C. immitis infections each year in the United States. Approximately 5% of these new cases progress to disseminated disease.