Epidemiology, clinical manifestations, and outcomes of Scedosporium infections among solid organ transplant recipients

Abstract

Background: Few studies of Scedosporium infections following solid organ transplantation have been performed in the era of induction immunosuppression and widespread antifungal prophylaxis.

Methods: We performed a single-center, retrospective study of transplant recipients from 2000 through 2010 who had a positive Scedosporium culture.

Results: Among 27 patients, 67% (n = 18) and 33% (n = 9) were infected with Scedosporium apiospermum and Scedosporium prolificans, respectively. A total of 67% received induction immunosuppression and 74% received prior antifungal therapy. Isolates were broadly resistant to antifungals. Of these patients, 59% (n = 16) were colonized by Scedosporium, and 41% (n = 11) had disease (scedosporiosis). No significant clinical differences were seen between species. Colonization occurred exclusively in the lungs of lung transplant recipients (LTR). Scedosporiosis followed lung transplantation in 55%, and other organ transplants (multivisceral [18%]; and heart, liver, small intestine [9% each]) in 45%. Scedosporiosis was preceded by colonization in 36%. Diseases included pneumonia (64%), mediastinitis (18%), and fungemia/disseminated infections (18%). The 6-month outcomes were death in 55%, progression in 18%, stability in 9%, and resolution in 18%. Patients who died had earlier onset scedosporiosis post transplant (median: 80.5 vs. 1388 days; P = 0.04), and were more likely to have mediastinitis or disseminated infections than pneumonia (100% vs. 29%; P = 0.06). The 3 patients who developed scedosporiosis >1 year post transplant survived. All patients who survived were treated with a voriconazole-containing regimen.

Conclusions: LTR were most susceptible to Scedosporium colonization and scedosporiosis, particularly within the lungs. Death was common with scedosporiosis in the first year after all types of organ transplants, consistent with profound immunosuppression and antifungal resistance, but not encountered thereafter.

Keywords: S. apiospermum; S. prolificans; Scedosporium; colonization; scedosporiosis; transplantation.