First Case of Trichoderma longibrachiatum CIED (Cardiac Implantable Electronic Device)-Associated Endocarditis in a Non-immunocompromised Host: Biofilm Removal and Diagnostic Problems in the Light of the Current Literature.

BACKGROUND: Trichoderma species are saprophytic filamentous fungi producing localized and invasive infections that are cause of morbidity and mortality, especially in immunocompromised patients, causing up to 53% mortality. Non-immunocompromised patients, undergoing continuous ambulatory peritoneal dialysis, are other targets of this fungus. Current molecular diagnostic tools, based on the barcode marker ITS, fail to discriminate these fungi at the species level, further increasing the difficulty associated with these infections and their generally poor prognosis.

CASE REPORT: We report on the first case of endocarditis infection caused by Trichoderma longibrachiatum in a 30-year-old man. This patient underwent the implantation of an implantable cardioverter defibrillator in 2006, replaced in 2012. Two years later, the patient developed fever, treated successfully with amoxicillin followed by ciprofloxacin, but an echocardiogram showed large vegetation onto the ventricular lead. After CIED extraction, the patient had high-grade fever. The culturing of the catheter tip was positive only in samples deriving from sonication according to the 2014 ESCMID guidelines, whereas the simple washing failed to remove the biofilm cells from the plastic surface. Subsequent molecular (ITS sequencing) and microbiological (macromorphology) analyses showed that the vegetation was due to T. longibrachiatum.

CONCLUSIONS: This report showed that T. longibrachiatum is an effective threat and that sonication is necessary for the culturing of vegetations from plastic surfaces. Limitations of the current barcode marker ITS, and the long procedures required by a multistep approach, call for the development of rapid monophasic tests.