Native valve endocarditis due to Pseudallescheria boydii in a patient with AIDS: case report and review. A 53-year-old man with AIDS developed mitral valve endocarditis due to infection with the fungus Pseudallescheria boydii. A limited number of cases of prosthetic valve endocarditis caused by this organism have been described. We report a unique case of pseudallescheria infection of a native valve and describe this disease in a patient with AIDS. 