Infective endocarditis caused by Scedosporium prolificans infection in a patient with acute myeloid leukemia undergoing induction chemotherapy

Disseminated Scedosporium prolificans infection occurs mainly in immunocompromised patients. The mortality rate is high, as the fungus is resistant to most antifungal agents. Here, we present the case of a 66-year-old female with acute myeloid leukemia who developed infective endocarditis caused by S. prolificans infection during induction chemotherapy. Her 1,3-β-D-glucan levels were elevated and computed tomography revealed bilateral sinusitis and disseminated small nodular masses within the lungs and spleen; it nonetheless took 6 days to identify S. prolificans by blood culture. The patient died of multi-organ failure despite the combined use of voriconazole and terbinafine. Autopsy revealed numerous mycotic emboli within multiple organs (caused by mitral valve vegetation) and endocarditis (caused by S. prolificans). The geographic distribution of this infection is limited to Australia, the United States, and southern Europe, particularly Spain. The first Japanese case was reported in 2011, and four cases have been reported to date, including this one. Recently, the incidence of S. prolificans-disseminated infection in immunocompromised patients has increased in Japan. Therefore, clinicians should consider S. prolificans infection as a differential diagnosis when immunocompromised patients suffer disseminated infections with elevated 1,3-β-D-glucan levels.