Abstract:Objective To identify the pathogen causing bloodstream infection (BSI) in an elderly patient and to describe its pathogenic characteristics. This study also reviews recent relevant literatures on Trichoderma longibrachiatum (T. longibrachiatum) infections. Methods Blood specimens from central and peripheral veins were co-llected for blood culture. The morphological characteristics and drug susceptibility of the isolated filamentous fungus were analyzed. The sequences of the isolated strains were detected using the internal transcribed spacer (ITS) region, and then analyzed using MEGA software. Results Both morphological observation and ITS sequencing su-ggested that the pathogen was T. longibrachiatum. The minimum inhibitory concentration (MIC) against the strain detected in accordance with the M38-A2 Guideline for the Drug Susceptibility of Filamentous Fungi issued by the Clinical and Laboratory Standards Institute (CLSI) of the United States showed that the MICs of micafungin, caspofungin, 5-fluorocytosine, posaconazole, voriconazole, itraconazole, fluconazole, anidulafungin and amphotericin were 8, 8, 64, 2, 0.5, 2, 64, 8 and 4 μg/mL respectively. The patient recovered well after anti-fungal treatment with voriconazole. A total of 15 cases of T. longibrachiatum infection were reported in the literature. The main underlying disease was transplantation (n=5), and the main clinical manifestation was pulmonary infection (n=5). Of these, 9 cases survived, 3 died, and 3 had an unknown prognosis. Conclusion T. longibrachiatum infection is more common in patients with low immunity and more underlying diseases, with a high fatality rate, lack standardized clinical treatment guidelines, lack break points in drug sensitivity results, and is resistant to common antifungal drugs. It is of guiding significance to isolate and identify pathogens in time and provide corresponding drug sensitivity testing results for clinical drug use.