Epidemiology and outcome of infections due to Aspergillus terreus: 10‐year single centre experience

Abstract

SummaryAspergillus terreus, a less common pathogen, appears to be an emerging cause of infection at our institution, the Medical University Hospital of Innsbruck. Thus the epidemiology and outcome of A. terreus infections over the past 10 years was assessed. We analysed 67 cases of proven invasive aspergillosis (IA) according to the European Organisation for Research and Treatment of Cancer/Mycoses Study Group criteria, investigated antifungal susceptibility of amphotericin B (AMB), voriconazole and caspofungin and performed molecular typing of A. terreus. Patients with proven IA caused by A. terreus (n ¼ 32) and non-A. terreus (n ¼ 35) were evaluated. The two groups were comparable in terms of age, gender, underlying disease, antifungal prophylaxis and duration of neutropenia (P > 0AE05). Leukaemia was the most common underlying malignancy. Fungal dissemination occurred in 63% of the patients. Aspergillus terreus infections were associated with a lower response rate to AMB therapy (20%), compared with 47% for patients with non-A. terreus infections (P < 0AE05). In vitro, A. terreus was found to be resistant to AMB and molecular typing discriminated between patients isolates, showing a high strain diversity with 26 distinct types (I-XXVI) identified by combination of three primers. Aspergillus terreus infections displayed evidence of AMB resistance in vitro and in vivo and were associated with a high rate of dissemination and poor outcome; A. terreus causes systemic infections of endemic character in Tyrol, Austria. The onset of A. terreus infection depends not on the degree of immunosuppression but on environmental Aspergillus spp. exposure.

Galleria mellonellaas a host model to studyAspergillus terreusvirulence and amphotericin B resistance

“…terreus isolates are known to show an intrinsic resistance to AMB with MIC values 2 mg/mL. 10,11,38 No clinical beakpoints for AMB are defined for A. terreus species, but regarding the EUCAST breakpoints for other Aspergillus spp, isolates with MIC values >2 mg/mL are considered to be clinically resistant against AMB. 39 Data from in vitro studies correlate well with murine studies.…”

“…8,9 In vivo and in vitro data indicate that A. terreus isolates are intrinsically resistant to amphotericin B (AMB) (MIC 2 mg/mL). 10,11 The mechanisms involved in AMB resistance are only partly elucidated and special focus has been put on comparing cellular and metabolic differences in AMB resistant isolates (ATR) to one susceptible isolate (ATS) from the University of Milano (MIC of 0.5 mg/mL).…”

Qualitative and Quantitative Assessment of Airborne Fungal Spores in the Hospitals Environment of Ahvaz City (2016)

“…Since A. terreus infections have displayed resistance to amphotericin B in vitro and in vivo, and due to the high rate of dissemination of this species in the study; management and more decontamination of hospital air are recommended. Lass-Florl et al (34) believed the beginning of fungal infection caused by A.terreus depends not on the immunosuppression degree but depends on environmental exposure to Aspergillus spores. In addition, A.terreus is suggested to be associated with hospital plants (35,36).…”

Successful Treatment of Lung Aspergillus terreus Infection After a Second Hematopoietic Stem Cell Transplant in a Patient With Myelodysplastic Syndrome

“…7 Treatment commonly fails, and the mortality rates are higher than those of other Aspergillus species. 8,9 Aspergillus terreus infections have prompted clinical interest because of their lack of response to amphotericin B and the relatively high percentage of clinical isolates with acquired resistance to azoles, particularly voriconazole. Isavuconazole has demonstrated potent in vitro antifungal activity against most Aspergillus species, including Aspergillus terreus strains that were resistant to amphotericin B.…”