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

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 Lateral-Flow Device for the Rapid Detection of Scedosporium Species

Scedosporium species are human pathogenic fungi, responsible for chronic, localised, and life-threatening disseminated infections in both immunocompetent and immunocompromised individuals. The diagnosis of Scedosporium infections currently relies on non-specific CT, lengthy and insensitive culture from invasive biopsy, and the time-consuming histopathology of tissue samples. At present, there are no rapid antigen tests that detect Scedosporium-specific biomarkers. Here, we report the development of a rapid (30 min) and sensitive (pmol/L sensitivity) lateral-flow device (LFD) test, incorporating a Scedosporium-specific IgG1 monoclonal antibody (mAb), HG12, which binds to extracellular polysaccharide (EPS) antigens between ~15 kDa and 250 kDa secreted during the hyphal growth of the pathogens. The test is compatible with human serum and allows for the detection of the Scedosporium species most frequently reported as agents of human disease (Scedosporium apiospermum, Scedosporium aurantiacum, and Scedosporium boydii), with limits of detection (LODs) of the EPS biomarkers in human serum of ~0.81 ng/mL (S. apiospermum), ~0.94 ng/mL (S. aurantiacum), and ~1.95 ng/mL (S. boydii). The Scedosporium-specific LFD (ScedLFD) test therefore provides a potential novel opportunity for the detection of infections caused by different Scedosporium species.

Cutaneous Hyalohyphomycosis and Its Atypical Clinical Presentations in Immunosuppressed Patients

There has been a substantial increase in the number of cases of invasive fungal infections worldwide, which is associated with a growing number of immunosuppressed patients and a rise in antifungal resistance. Some fungi that were previously considered harmless to humans have become emerging pathogens. One of them is Purpureocillium lilacinum, a ubiquitous filamentous fungus commonly found in the environment, especially in the air and soil. P. lilacinum belongs to a bigger group of hyaline fungi that cause hyalohyphomycosis, a fungal infection caused by fungi with colorless hyphae. Although this is a heterogeneous group of fungi, there are similarities regarding their ubiquity, ways of transmission, affected patients, and difficulties in diagnostics and treatment. In hyalohyphomycosis, the skin is one of the most affected organs, which is why the involvement of dermatologists is crucial for the initial assessment, since the timely recognition and early diagnosis of this condition can prevent life-threatening infections and death. In this review, we covered cutaneous hyalohyphomycosis caused by P. lilacinum and other fungi in the same group, including Fusarium, Penicilium, Scedosporium, Scopulariopsis, Acremonium, and Trichoderma genera.

Skin lesions by Scedosporium apiospermum and Nocardia pulmonary infection in an oncologic patient: a case report

BACKGROUND

Fungal infections, other than candidiasis and aspergillosis, are an uncommon entity. Despite this, emerging pathogens are a growing threat. In the following case report, we present the case of an immunocompromised patient suffering from two serious opportunistic infections in the same episode: the first of these, Nocardia multilobar pneumonia; and the second, skin infection by Scedosporium apiospermum. These required prolonged antibacterial and antifungal treatment.

CASE PRESENTATION

This case is a 71-year-old oncological patient admitted for recurrent pneumonias that was diagnosed for Nocardia pulmonary infection. Nervous system involvement was discarded and cotrimoxazole was started. Haemorrhagic skin ulcers in the lower limbs appeared after two weeks of hospital admission. We collected samples which were positive for Scedosporium apiospermum and we added voriconazole to the treatment. As a local complication, the patient presented a deep bruise that needed debridement. We completed 4 weeks of intravenous treatment with slow improvement and continued with oral treatment until the disappearance of the lesions occurs.

CONCLUSIONS

Opportunistic infections are a rising entity as the number of immunocompromised patients is growing due to more use of immunosuppressive therapies and transplants. Clinicians must have a high suspicion to diagnose and treat them. A fluid collaboration with Microbiology is necessary as antimicrobial resistance is frequent.

Development and efficacy of tryptophol-containing emulgel for reducing subcutaneous fungal nodules from Scedosporium apiospermum eumycetoma

Background and purpose

Subcutaneous infections caused by Scedosporium apiospermum present as chronic eumycetomatous manifestations in both immunocompromised and immunocompetent individuals. Serious adverse effects/toxicities from the long-term use of antifungal drugs and antifungal resistance have been reported in patients with S. apiospermum infections. The present study aimed to determine the anti-S. apiospermum activities of fungal quorum sensing molecule known as tryptophol (TOH) and to develop a TOH-containing emulgel for treating S. apiospermum eumycetoma.

Experimental approach

Anti-S. apiospermum activities of TOH were determined and compared with voriconazole. Effects of TOH on S. apiospermum biofilm formation and human foreskin fibroblast (HFF)-1 cell cytotoxicity were determined. Moreover, TOH-containing emulgel was developed and physical properties, in vitro, and in vivo antifungal activities against S. apiospermum eumycetoma were evaluated.

Findings/Results

The minimal concentration of TOH at 100 µM exhibited anti-S. apiospermum activities by reducing growth rate, germination rate, and biofilm formation with less cytotoxicity to HFF-1 cells than voriconazole. Further study on the development of an emulgel revealed that TOH-containing emulgel exhibited excellent physical properties including homogeneity, consistency, and stability. Treatment by TOH-containing emulgel significantly reduced subcutaneous mass in a mouse model of S. apiospermum eumycetoma. The histopathological assessment showed marked improvement after 14 days of TOH-containing emulgel treatment.

Conclusion and implications

TOH could be used as an anti-fungal agent against S. apiospermum infections. A novel and stable TOH-containing emulgel was developed with excellent anti-S. apiospermum activities suggesting the utilization of TOH-containing emulgel as an innovative therapeutic approach in the treatment of S. apiospermum eumycetoma.

Invasive and Subcutaneous Infections Caused by Filamentous Fungi: Report from a Portuguese Multicentric Surveillance Program

Invasive fungal infections (IFI) have significantly increased over the past years due to advances in medical care for the at-risk immunocompromised population. IFI are often difficult to diagnose and manage, and can be associated with substantial morbidity and mortality. This study aims to contribute to understanding the etiology of invasive and subcutaneous fungal infections, their associated risk factors, and to perceive the outcome of patients who developed invasive disease, raising awareness of these infections at a local level but also in a global context. A laboratory surveillance approach was conducted over a seven-year period and included: (i) cases of invasive and subcutaneous fungal infections caused by filamentous/dimorphic fungi, confirmed by either microscopy or positive culture from sterile samples, (ii) cases diagnosed as probable IFI according to the criteria established by EORTC/MSG when duly substantiated. Fourteen Portuguese laboratories were enrolled. Cases included in this study were classified according to the new consensus definitions of invasive fungal diseases (IFD) published in 2020 as follows: proven IFI (N = 31), subcutaneous fungal infection (N = 23). Those proven deep fungal infections (N = 54) totalized 71.1% of the total cases, whereas 28.9% were classified as probable IFI (N = 22). It was possible to identify the etiological fungal agent in 73 cases (96%). Aspergillus was the most frequent genera detected, but endemic dimorphic fungi represented 14.47% (N = 11) of the total cases. Despite the small number of cases, a high diversity of species were involved in deep fungal infections. This fact has implications for clinical and laboratory diagnosis, and on the therapeutic management of these infections, since different species, even within the same genus, can present diverse patterns of susceptibility to antifungals.

A case of bilateral injection abscesses caused by Graphium type of Scedosporium apiospermum

Fungal infections with non-Aspergillus species are increasingly reported even among immunocompetent individuals. We report a case of bilateral injection abscesses by Scedosporium apiospermum in an immunocompetent patient. This rare fungus was isolated and identified by culture from the surgical tissue and was confirmed by Vitek MS and sequencing of the internal transcribed spaces region of rDNA. The patient is being treated with Voriconazole for the past 3 months with no recurrence of the abscesses.

Scedosporium apiospermum infection of the lumbar vertebrae: A case report

BACKGROUND

Scedosporium apiospermum (S. apiospermum) is a clinically rare and aggressive fungus mainly found in contaminated water, wetlands, decaying plants, stagnant water, and potted plants in hospitals. The lung, bone, joint, eye, brain, skin, and other sites are easily infected, and there is a marked risk of misdiagnosis. There have been few case reports of infection by S. apiospermum of the lumbar vertebrae; most reports have focused on infection of the lung.

CASE SUMMARY

An otherwise healthy 60-year-old man presented with a 4-mo history of lumbosacral pain, stooping, and limited walking. The symptoms were significantly aggravated 10 d prior to hospitalization, and radiating pain in the back of his left lower leg developed, which was so severe that he could not walk. Movement of the lumbar spine was significantly limited, anterior flexion was about 30°; backward extension, right and left lateral curvature, and rotational mobility were about 10°; tenderness of the spinous processes of the lumbar 3-5 vertebrae was evident, and the muscle strength of both lower limbs was grade IV. Imaging suggested bony destruction of the lumbar 3, 4, and 5 vertebrae and sacral 1 vertebra; in addition, the corresponding intervertebral spaces were narrowed and the lumbar 5 vertebra was posteriorly displaced and unstable. Lumbar vertebral infection was also noted, and the possibility of lumbar tuberculosis was considered. We first performed surgical intervention on the lesioned lumbar vertebrae, cleared the infected lesion, and performed stable fixation of the lesioned vertebral body using a lumbar internal fixation device, which restored the stability of the lumbar vertebrae. Cytological and pathological examination of the lesioned tissue removed during surgery confirmed S. apiospermum infection of the lumbar vertebrae; on this basis, the patient was administered voriconazole. At the 6-mo follow-up, efficacy was significant, no drug-related side effects were observed, and imaging examination showed no evidence of recurrence.

CONCLUSION

S. apiospermum infection can occur in immunocompetent individuals with no history of near drowning. Voriconazole is effective for the treatment of S. apiospermum infection of the lumbar vertebrae for which it is suitable as the first-line therapy.

Eumycetoma Medical Treatment: Past, Current Practice, Latest Advances and Perspectives

Mycetoma is a neglected tropical disease that is associated with poor communities and socioeconomically impaired individuals in the tropical and sub-tropical areas. Interestingly, the disease is caused by either bacteria (actinomycetoma) or fungus (eumycetoma). The latter form of the disease, eumycetoma, is the most common type in Africa. Eumycetoma is characterized by a prolonged disease duration and low cure rate. The effective case management of eumycetoma largely depends on the accurate diagnosis and identification of the causative agent to the species level and evaluating its susceptibility to the available drugs. This review summarizes the currently available and used antifungal agents for the treatment of eumycetoma and discusses optimizing the newly developed antifungals as a potential second line for eumycetoma treatment.

Scedosporium apiospermum fungemia successfully treated with voriconazole and terbinafine

Scedosporium apiospermum is ubiquitous in the environment and is considered an emerging infection. Immunocompromised hosts can have a wide spectrum of diseases ranging from cutaneous to disseminated disease that may involve pulmonary, central nervous system, or bone. Disseminated disease in immunocompetent hosts is uncommon. Treatment of deep-seated infections is challenging because of the limited susceptibility of the Scedosporium species to all current antifungal drugs. We report a case of Scedosporidium apiospermum fungemia with a presumed pulmonary involvement in an immunocompetent patient. The fungemia was successfully treated with oral voriconazole and terbinafine.

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.

Pulmonary Scedosporium apiospermum Infection with Pulmonary Tumorlet in an Immunocompetent Patient

Scedosporium apiospermum is an opportunistic fungus that can cause various types of infections, including localized infections and life-threatening disseminated infections, particularly in immunocompromised patients. Treatment is especially challenging due to its multidrug resistance. We herein report the case of a 73-year-old woman who was non-immunocompromised but developed S. apiospermum lung infection and a pulmonary tumorlet. To our knowledge, this is the first report of the coexistence of pulmonary S. apiospermum infection and tumorlet. The lung lesion was successfully treated by surgical excision without any antifungal agents, and no recurrence of the tumorlet or S. apiospermum infection has occurred.