Aspergillus galactomannan detection: Trichoderma as a cause of positive results

Invasive Trichoderma longibrachiatum infection in a neutropaenic patient

Invasive fungal infection is a life-threatening complication of chemotherapy and neutropaenia in the haematology population. Trichoderma species rarely cause human disease but have been reported to cause invasive infection in the immunosuppressed. We present a case of invasive Trichoderma longibrachiatum pulmonary infection with fatal outcome in a neutropaenic patient with acute myeloid leukaemia. 2012 Elsevier Ltd. All rights reserved.

Invasive Trichoderma spp. infections: clinical presentation and outcome of cases from the literature and the FungiScope® registry

Background

Trichoderma spp. are filamentous fungi causing invasive fungal diseases in patients with haematological malignancies and in peritoneal dialysis patients.

Objectives

To analyse clinical presentation, predisposing factors, treatment and outcome of Trichoderma infections.

Methods

A systematic literature review was conducted for published cases of invasive Trichoderma infection in PubMed until December 2021 and by reviewing the included studies’ references. Cases from the FungiScope^® registry were added to a combined analysis.

Results

We identified 50 invasive infections due to Trichoderma species, including 11 in the FungiScope^® registry. The main underlying conditions were haematological malignancies in 19 and continuous ambulatory peritoneal dialysis (CAPD) in 10 cases. The most prevalent infection sites were lung (42%) and peritoneum (22%). Systemic antifungal therapy was administered in 42 cases (84%), mostly amphotericin B (n = 27, lipid-based formulation 13/27) and voriconazole in 15 cases (30%). Surgical interventions were performed in 13 cases (26%). Overall mortality was 48% (n = 24) and highest for allogeneic HSCT and solid organ transplantation (SOT) recipients [80% (4/5) and 77% (7/9), respectively]. In patients treated with amphotericin B, voriconazole and caspofungin, mortality was 55% (15/27), 46% (7/15) and 28% (2/7), respectively. Three out of four patients treated with a combination therapy of voriconazole and caspofungin survived.

Conclusions

Despite treatment with antifungal therapies and surgery, invasive Trichoderma infections are life-threatening complications in immunocompromised patients, especially after HSCT and SOT. In addition, Trichoderma spp. mainly affect the lungs in patients with haematological malignancies and the peritoneum in CAPD patients.

Serology anno 2021-fungal infections: from invasive to chronic

BACKGROUND

Diagnosing invasive or chronic fungal infections is a challenge, particularly in the immunocompromised host. Microscopy and culture remain the reference standard, but are insensitive. The use of non-culture-based techniques is recommended in conjunction with conventional methods to improve the diagnostic yield.

OBJECTIVES

The aim was to provide an updated 2021 inventory of fungal antigen and serology tests for diagnosing invasive and chronic fungal infections, the key focus was set on Aspergillus, Candida and Cryptococcus species.

SOURCES

Pubmed search for publications with the key words fungal antigen tests, laboratory-based diagnosis of invasive pulmonary aspergillosis, chronic pulmonary aspergillosis, invasive candidiasis, invasive fungal infections and cryptococcal infections published from 2017 to 2020.

CONTENT

Antigen assays such as the galactomannan (GM) and β-d-glucan detection systems are frequently used, but these tests vary in sensitivity and specificity, depending on the patient population involved, specimens inspected, cut-offs defined, test strategy applied and inclusion or exclusion of possible fungal case definitions. Multiple different detection systems are available, with recently introduced new point-of-care tests such as the lateral flow device and the lateral flow assay. Despite a wide heterogeneity in populations evaluated, studies indicate a better diagnostic performance of bronchoalveolar lavage GM in comparison with serum GM, and a suboptimal specificity of GM bronchoalveolar lavages (cut-off ≥1) and serum β-d-glucan in non-neutropenic individuals. Point-of-care cryptococcal antigen tests show excellent performance.

IMPLICATIONS

There are fungal antigen detection tests available with excellent to reasonable clinical performance to diagnose invasive fungal infections. Only a few assays are useful to monitor therapeutic response. There are multiple marketed IgG antibody tests to detect Aspergillus fumigatus antibodies, the titres vary widely and the performance differs significantly. In general, diagnostic tests are vulnerable to being affected by the host, the microbe and laboratory setting.