Pulmonary zygomycosis.

Zygomycosis has emerged as an increasingly common infection in immunocompromised patients. Although the majority of these cases are community acquired, hospital outbreaks have been described, linked to the use of contaminated products. Risk factors for development of zygomycosis include uncontrolled diabetes mellitus, neutropenia, use of immunosuppressive medications, and iron overload states. Recent studies have shown the central role of iron in the pathogenesis of zygomycosis and the effect of disease states such as ketoacidosis and hyperglycemia on the availability of iron to the Zygomycetes. These organisms most commonly infect the sinuses, lungs, central nervous system, and skin and soft tissues. Diagnosis often involves invasive procedures, including deep tissue biopsy, because radiological studies are not specific for this disease, and other less invasive diagnostic modalities have not yet been proven to be sensitive or specific. Treatment may require a combined medical and surgical approach in these frequently frail patients; yet, even with such aggressive measures the mortality of zygomycosis remains high.