Mixed angioinvasive exserohilum and scedosporium infection in a patient with AML

Scedosporiosis and lomentosporiosis: modern perspectives on these difficult-to-treat rare mold infections

SUMMARYAlthough Scedosporium species and Lomentospora prolificans are uncommon causes of invasive fungal diseases (IFDs), these infections are associated with high mortality and are costly to treat with a limited armamentarium of antifungal drugs. In light of recent advances, including in the area of new antifungals, the present review provides a timely and updated overview of these IFDs, with a focus on the taxonomy, clinical epidemiology, pathogenesis and host immune response, disease manifestations, diagnosis, antifungal susceptibility, and treatment. An expansion of hosts at risk for these difficult-to-treat infections has emerged over the last two decades given the increased use of, and broader population treated with, immunomodulatory and targeted molecular agents as well as wider adoption of antifungal prophylaxis. Clinical presentations differ not only between genera but also across the different Scedosporium species. L. prolificans is intrinsically resistant to most currently available antifungal agents, and the prognosis of immunocompromised patients with lomentosporiosis is poor. Development of, and improved access to, diagnostic modalities for early detection of these rare mold infections is paramount for timely targeted antifungal therapy and surgery if indicated. New antifungal agents (e.g., olorofim, fosmanogepix) with novel mechanisms of action and less cross-resistance to existing classes, availability of formulations for oral administration, and fewer drug-drug interactions are now in late-stage clinical trials, and soon, could extend options to treat scedosporiosis/lomentosporiosis. Much work remains to increase our understanding of these infections, especially in the pediatric setting. Knowledge gaps for future research are highlighted in the review.

Fusarium, Scedosporium and Other Rare Mold Invasive Infections: Over Twenty-Five-Year Experience of a European Tertiary-Care Center

Invasive mold infections (IMD) are an emerging concern due to the growing prevalence of patients at risk, encompassing but not limited to allogeneic hematopoietic stem cell transplant recipients, hematological malignancies patients, solid organ transplant recipients and intensive care unit patients. In contrast with invasive aspergillosis and mucormycosis, other hyalohyphomycoses and phaeohyphomycoses remain poorly known. We conducted a retrospective analysis of the clinical, biological, microbiological and evolutive features of 92 IMD having occurred in patients in our tertiary-care center over more than 25 years. A quarter of these infections were due to multiple molds. Molds involved were Fusarium spp. (36.2% of IMD with a single agent, 43.5% of IMD with multiple agents), followed by Scedosporium spp. (respectively 14.5% and 26.1%) and Alternaria spp. (respectively 13.0% and 8.7%). Mortality at day 84 was higher for Fusarium spp., Scedosporium spp. or multiple pathogens IMD compared with Alternaria or other pathogens (51.7% vs. 17.6%, p < 0.05). Mortality at day 84 was also influenced by host factor: higher among hematology and alloHSCT patients than in other patients (30.6% vs. 20.9% at day 42 and 50.0% vs. 27.9% at day 84, p = 0.041). Better awareness, understanding and treatments are awaited to improve patient prognosis.

Lomentospora prolificans Disseminated Infections: A Systematic Review of Reported Cases

BACKGROUND

Lomentospora prolificans, a rare, highly virulent filamentous fungus with high rates of intrinsic resistance to antifungals, has been associated with different types of infections in immunocompromised as well as immunocompetent individuals.

OBJECTIVE

To systematically address all relevant evidence regarding L. prolificans disseminated infections in the literature.

METHODS

We searched Medline via PubMed and Scopus databases through July 2022. We performed a qualitative synthesis of published articles reporting disseminated infections from L. prolificans in humans.

RESULTS

A total of 87 studies describing 142 cases were included in our systematic review. The pathogen was most frequently reported in disseminated infections in Spain (n = 47), Australia (n = 33), the USA (n = 21), and Germany (n = 10). Among 142 reported cases, 48.5% were males. Underlying conditions identified for the majority of patients included malignancy (72.5%), hemopoietic stem cell transplantation (23.2%), solid organ transplantation (16%), and AIDS (2%). Lungs, central nervous system, skin, eyes, heart and bones/joints were the most commonly affected organs. Neutropenia was recorded in 52% of patients. The mortality rate was as high as 87.3%.

CONCLUSIONS

To the best of our knowledge, this is the first systematic review conducted on disseminated infections due to this rare microorganism. Physicians should be aware that L. prolificans can cause a diversity of infections with high mortality and primarily affects immunocompromised and neutropenic patients.