Pulmonary blastomycosis.

Blastomyces dermatitidis is acquired in almost all cases via inhalation, and pulmonary disease is the most frequent clinical manifestation of blastomycosis. Pulmonary disease can range from asymptomatic infection to rapidly severe and fatal disease. Most cases will present as pneumonia, either acute or chronic, or as a lung mass. In rare cases pulmonary blastomycosis is associated with the acute respiratory distress syndrome. Blastomycosis can present as isolated pulmonary disease or along with coexisting extrapulmonary disease that usually will involve the skin, bony structures, genitourinary tract, or central nervous system. Diagnosis is largely based on isolation of the organism via culture or visualization of the organism in clinical specimens. Detection of urinary Blastomyces antigen is a recent addition to diagnostic options. Itraconazole is the drug of choice for most forms of the disease; amphotericin B is reserved for the more severe forms. Newer azoles such as voriconazole and posaconazole have a limited role in the treatment of pulmonary blastomycosis.