Endocarditis due to Trichosporon beigelii: In vitro susceptibility of isolates and review

Infection with Trichosporon beigelii is an uncommon cause of endocarditis. Of the eight cases of T. beigelii endocarditis that have been reported (one herein and seven previously), six involved prosthetic heart valves and two involved native heart valves. The clinical manifestations of this infection included embolization of the superficial femoral artery or of the bifurcation of the posterior tibial and peroneal arteries in three of these patients (two with prosthetic valve and one with native valve endocarditis). In seven of the eight reported cases, blood cultures were positive for the organism. Although clinical isolates of the organism are generally reported to be susceptible to amphotericin B, isolates can vary in their sensitivities to antifungal agents in vitro depending on the methodology used, and clinical response to therapy with antifungal agents in a regimen that includes amphotericin B is generally poor. Only two of six patients who were treated with antifungal agents survived endocarditis caused by T. beigelii and were apparently cured; one of these patients was also managed surgically with valve replacement. Infection with T. beigelii should be considered in the differential diagnosis of endocarditis in immunocompetent patients, particularly those who have a prosthetic heart valve. Rapid, aggressive therapy may be necessary to eradicate this organism.