Successful treatment of Scedosporium apiospermum soft tissue abscess with caspofungin and voriconazole in a severely immunocompromised patient with acute myeloid leukemia

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.

A rare case of scedosporium apiospermum osteomyelitis in an immunocompetent patient

Scedosporium, a widespread filamentous fungus found in diverse environments, has experienced a rise in cases due to escalating malignancies and chronic immunosuppression. Clinical manifestations span mycetoma, airway involvement, and various infections, with osteomyelitis being a notable complication. We present a case of a 77-year-old female initially displaying cutaneous Scedosporium signs, which progressed to osteomyelitis. The patient, with a history of trauma, chronic low dose steroid use, and underlying conditions, presented with a foot injury caused by her dog. Despite initial management, worsening symptoms led to the identification of Scedosporium. A comprehensive approach involving debridement, antimicrobial therapy, and reduction of immunosuppression resulted in clinical improvement. The rarity of zoonotic transmission, diagnostic challenges, and antifungal efficacy are also discussed. The patient's positive trajectory emphasizes early diagnosis, targeted treatment, and vigilance in managing immunosuppression. An adaptable treatment protocol is proposed based on risk factors. Considering the rising opportunistic fungal infections and delayed culture results, initiating empirical antifungals based on clinical judgment and regional prevalence is vital for favorable outcomes.

Consensus guidelines for the diagnosis and management of invasive fungal disease due to moulds other than Aspergillus in the haematology/oncology setting, 2021

Invasive fungal disease (IFD) due to moulds other than Aspergillus is a significant cause of mortality in patients with malignancies or post haemopoietic stem cell transplantation. The current guidelines focus on the diagnosis and management of the common non-Aspergillus moulds (NAM), such as Mucorales, Scedosporium species (spp.), Lomentospora prolificans and Fusarium spp. Rare but emerging NAM including Paecilomyces variotii, Purpureocillium lilacinum and Scopulariopsis spp. are also reviewed. Culture and histological examination of tissue biopsy specimens remain the mainstay of diagnosis, but molecular methods are increasingly being used. As NAM frequently disseminate, blood cultures and skin examination with biopsy of any suspicious lesions are critically important. Treatment requires a multidisciplinary approach with surgical debridement as a central component. Other management strategies include control of the underlying disease/predisposing factors, augmentation of the host response and the reduction of immunosuppression. Carefully selected antifungal therapy, guided by susceptibility testing, is critical to cure. We also outline novel antifungal agents still in clinical trial which offer substantial potential for improved outcomes in the future. Paediatric recommendations follow those of adults. Ongoing epidemiological research, improvement in diagnostics and the development of new antifungal agents will continue to improve the poor outcomes that have been traditionally associated with IFD due to NAM.

Tryptophol Coating Reduces Catheter-Related Cerebral and Pulmonary Infections by Scedosporium apiospermum

Introduction

Central venous catheter (CVC) is a medical device that is used to administer medication for a long duration. Colonization by an emerging opportunistic pathogen Scedosporium apiospermum in the CVC lumen is frequently reported to cause severe complications in patients. Here, we describe the effect of fungal quorum-sensing molecule (QSM) known as tryptophol (TOH) to control S. apiospermum colonization in catheter tube lumens in both in vitro and in vivo models.

Methods

Antifungal susceptibility of TOH against S. apiospermum was compared with voriconazole, and the colony diameter was determined on days 2, 4, and 6. Experimental catheterization rat model was conducted with pre-coating of TOH and voriconazole or an uncoated control and an infection with S. apiospermum. Biofilm formation on the catheter luminal surface was assessed using the scanning electron microscopy, crystal violet, and 2,3-bis(2-methoxy-4-ni-tro-5-sulfophenyl)-5-(phenylamino)-carbonyl-2H-tetra-zolium hydroxide (XTT) reduction assays. Brain and lung samples of catheterized rats were histopathologically assessed. Serum samples from catheterized rats were injected into Galleria mellonella larvae. Survival of catheterized rats and G. mellonella was determined.

Results

TOH impeded the growth of S. apiospermum by reducing the colony diameter in a dose-dependent manner. TOH coating remarkably lessened S. apiospermum biofilm formation and fungal cell viability on the catheter luminal surface. Additionally, TOH coating lessens cerebral edema that is associated with abscess and invasive pulmonary damages due to S. apiospermum catheter-related infection. Furthermore, TOH coating also lessened the virulence of S. apiospermum in sera of experimental catheterized rats and extended the survival rate of larvae Galleria mellonella infection model.

Conclusion

An alternative modification of catheter by coating with TOH is effective in preventing S. apiospermum colonization in vivo. Our study gives a new strategy to control catheter contamination and prevents nosocomial diseases due to S. apiospermum infection.

Recurrent Scedosporium apiospermum mycetoma successfully treated by surgical excision and terbinafine treatment: a case report and review of the literature

Background

Scedosporium apiospermum is an emerging opportunistic filamentous fungus, which is notorious for its high levels of antifungal-resistance. It is able to cause localized cutaneous or subcutaneous infections in both immunocompromised and immunocompetent persons, pulmonary infections in patients with predisposing pulmonary diseases and invasive mycoses in immunocompromised patients. Subcutaneous infections caused by this fungus frequently show chronic mycetomatous manifestation.

Case report

We report the case of a 70-year-old immunocompromised man, who developed a fungal mycetomatous infection on his right leg. There was no history of trauma; the aetiological agent was identified by microscopic examination and ITS sequencing. This is the second reported case of S. apiospermum subcutaneous infections in Hungary, which was successfully treated by surgical excision and terbinafine treatment. After 7 months, the patient remained asymptomatic. Considering the antifungal susceptibility and increasing incidence of the fungus, Scedosporium related subcutaneous infections reported in the past quarter of century in European countries were also reviewed.

Conclusions

Corticosteroid treatment represents a serious risk factor of S. apiospermum infections, especially if the patient get in touch with manure-enriched or polluted soil or water. Such infections have emerged several times in European countries in the past decades. The presented data suggest that besides the commonly applied voriconazole, terbinafine may be an alternative for the therapy of mycetomatous Scedosporium infections.

ESCMID and ECMM joint guidelines on diagnosis and management of hyalohyphomycosis: Fusarium spp., Scedosporium spp. and others

Mycoses summarized in the hyalohyphomycosis group are heterogeneous, defined by the presence of hyaline (non-dematiaceous) hyphae. The number of organisms implicated in hyalohyphomycosis is increasing and the most clinically important species belong to the genera Fusarium, Scedosporium, Acremonium, Scopulariopsis, Purpureocillium and Paecilomyces. Severely immunocompromised patients are particularly vulnerable to infection, and clinical manifestations range from colonization to chronic localized lesions to acute invasive and/or disseminated diseases. Diagnosis usually requires isolation and identification of the infecting pathogen. A poor prognosis is associated with fusariosis and early therapy of localized disease is important to prevent progression to a more aggressive or disseminated infection. Therapy should include voriconazole and surgical debridement where possible or posaconazole as salvage treatment. Voriconazole represents the first-line treatment of infections due to members of the genus Scedosporium. For Acremonium spp., Scopulariopsis spp., Purpureocillium spp. and Paecilomyces spp. the optimal antifungal treatment has not been established. Management usually consists of surgery and antifungal treatment, depending on the clinical presentation.

Autochthonous cases of mycetoma in Europe: report of two cases and review of literature

BACKGROUND

Mycetoma is a chronic granulomatous infection involving cutaneous and subcutaneous tissues. It is endemic in tropical and subtropical areas, but sporadic cases have been reported also in countries of temperate climate. The purpose of this paper is to review the cases of mycetoma in European subjects (and presumably acquired in Europe), to give an insight in the main factors associated with this condition, and to describe two previously unpublished cases observed at our Centre.

METHODS AND FINDINGS

PubMed was systematically searched for case reports and case series of mycetoma in Europeans reported between 1980 and 2014, using specific search strategies. Two further cases diagnosed by the authors are described. Forty-two cases were collected. Eleven cases were caused by Scedosporium apiospermium, mainly in immunosuppressed patients from Bulgaria, Germany, the Netherlands, Portugal, Slovenia, Spain and the United Kingdom. Excluding all patients with immunosuppression, 29 cases remain. Most of them were reported from Bulgaria and in Albanian patients (all diagnosed outside Albania). In the Bulgarian case series many different micro-organisms, both bacteria and fungi, were isolated, while all the 5 cases from Albania were caused by Actinomadura spp. Other countries reporting cases were Greece, Italy and Turkey. In general, Actinomadura spp is the most frequent causative agent isolated, followed by Nocardia spp and Madurella mycetomatis. The foot was the most reported site involved. Most patients were medically treated, but unfortunately a long-term follow up (at least one year) was available only in a few cases.

CONCLUSIONS

Our review and our own cases suggest that Europeans without travel history can be affected by Madura foot. The lack of a surveillance system is likely to cause an underreporting of cases. Moreover, the unfamiliarity of Western doctors with this peculiar infection may cause a mismanagement, including unnecessary amputations.

Scedosporium apiospermum catheter-related soft-tissue infection: a case report and review of the literature

We report a case of catheter-related Scedosporium apiospermum soft-tissue infection. This ubiquitous filamentous fungus can cause human infection after traumatic subcutaneous implantation of its conidia or their inhalation in near-drowning cases. It has also been reported as an etiological agent in a growing number of hospital-acquired infections.