A 16-year-old male with bone marrow failure due to chemotherapy for recurre
nt acute lymphoblastic leukemia developed an abscess in the lower lobe of t
he left lung draining through a bronchogastric fistula, as well as mitral v
alve endocarditis with large vegetations. After a course of antifungal ther
apy, the left lobe was removed and the fistula closed. The mitral valve was
then replaced, after a failed attempt at valve repair, by a mechanical, do
uble-leaflet prosthesis. Microscopy of the lung and heart specimens disclos
ed hyphae. Cultures of both specimens on Sabouraud's medium recovered a fun
gus, which was identified by culturing on Czapek's medium as Aspergillus fl
avus. Despite further antifungal therapy, fatal embolism developed. The emb
oli contained the same A. flavus as the valve and lung specimens. This case
confirms the grim prognosis of primary Aspergillus endocarditis in immunoc
ompromised patients, and suggests that delayed surgical treatment and the p
resence of another focus of Aspergillus infection may increase the risk of
death.