Septic arthritis due to Scedosporium apiospermum: case report and review

A systemic infection involved in lung, brain and spine caused by Scedosporium apiospermum species complex after near-drowning: a case report and literature review

Scedosporium apiospermum species complex are widely distributed fungi that can be found in a variety of polluted environments, including soil, sewage, and decaying vegetation. Those opportunistic pathogens with strong potential of invasion commonly affect immunosuppressed populations However, few cases of scedosporiosis are reported in immunocompetent individuals, who might be misdiagnosed, leading to a high mortality rate. Here, we reported an immunocompetent case of systemtic infection involved in lung, brain and spine, caused by S. apiospermum species complex (S. apiospermum and S. boydii). The patient was an elderly male with persistent fever and systemtic infection after near-drowning. In the two tertiary hospitals he visited, definite diagnosis was extremely difficult. After being admitted to our hospital, he was misdiagnosed as tuberculosis infection, before diagnosis of S. apiospermum species complex infection by the metagenomic next-generation sequencing. His symptoms were alleviated after voriconazole treatment. In the present case, the details associated with its course were reported and published studies on Scedosporium spp. infection were also reviewed, for a better understanding of this disease and reducing the misdiagnosis rate.

A Case of Invasive Fungal Infection Due to Scedosporium apiospermum in a Patient with Psoriasis

Scedosporium apiospermum (S. apiospermum) is typically reported to be involved in superficial and subcutaneous fungal infections but overlooked in invasive infections, which is associated with a high mortality rate. It poses a diagnostic challenge due to its confusable characteristics to other hyaline hyphomycetes. Here, we reported a psoriasis patient with an invasive S. apiospermum infection. The patient presents an abscess at the intermuscular space of the left hip and an increased C-reactive protein level. Pus culture showed white-greyish, cottonlike colonies with aerial mycelium and terminal oval conidia, suggesting S. apiospermum. This rare fungus was rapidly confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and RNA sequencing. The patient was successfully treated with voriconazole with no recurrence of the abscesses despite delayed treatment. This is the first such case infection report from China that described an unusual case of intermuscular space abscesses due to S. apiospermum. This report highlights the possibility of fungal infections in deeper tissue, as well as the necessity of thorough evaluation and microbiological diagnosis for invasive infections, particularly in immunocompromised patients.

Molecular epidemiology of clinical filamentous fungi in Qatar beyond Aspergillus and Fusarium with notes on the rare species

Due to an increasing number of patients at risk (i.e., those with a highly compromised immune system and/or receiving aggressive chemotherapy treatment), invasive fungal infections (IFI) are increasingly being reported and associated with high mortality rates. Aspergillus spp., particularly A. fumigatus, is the major cause of IFI caused by filamentous fungi around the world followed by Fusarium spp., however, other fungi are emerging as human pathogens. The aim of this study was to explore the epidemiology and prevalence of the non-Aspergillus and non-Fusarium filamentous fungi in human clinical samples over an 11-year period in Qatar using molecular techniques. We recovered 53 filamentous fungal isolates from patients with various clinical conditions. Most patients were males (75.5%), 9.4% were immunocompromised, 20.7% had IFI, and 11.3% died within 30 days of diagnosis. The fungal isolates were recovered from a variety of clinical samples, including the nasal cavity, wounds, respiratory samples, body fluids, eye, ear, tissue, abscess, and blood specimens. Among the fungi isolated, 49% were dematiaceous fungi, followed by Mucorales (30%), with the latter group Mucorales being the major cause of IFI (5/11, 45.5%). The current study highlights the epidemiology and spectrum of filamentous fungal genera, other than Aspergillus and Fusarium, recovered from human clinical samples in Qatar, excluding superficial infections, which can aid in the surveillance of uncommon and emerging mycoses.

Osteoarticular Mycoses

Osteoarticular mycoses are chronic debilitating infections that require extended courses of antifungal therapy and may warrant expert surgical intervention. As there has been no comprehensive review of these diseases, the International Consortium for Osteoarticular Mycoses prepared a definitive treatise for this important class of infections. Among the etiologies of osteoarticular mycoses are Candida spp., Aspergillus spp., Mucorales, dematiaceous fungi, non-Aspergillus hyaline molds, and endemic mycoses, including those caused by Histoplasma capsulatum, Blastomyces dermatitidis, and Coccidioides species. This review analyzes the history, epidemiology, pathogenesis, clinical manifestations, diagnostic approaches, inflammatory biomarkers, diagnostic imaging modalities, treatments, and outcomes of osteomyelitis and septic arthritis caused by these organisms. Candida osteomyelitis and Candida arthritis are associated with greater events of hematogenous dissemination than those of most other osteoarticular mycoses. Traumatic inoculation is more commonly associated with osteoarticular mycoses caused by Aspergillus and non-Aspergillus molds. Synovial fluid cultures are highly sensitive in the detection of Candida and Aspergillus arthritis. Relapsed infection, particularly in Candida arthritis, may develop in relation to an inadequate duration of therapy. Overall mortality reflects survival from disseminated infection and underlying host factors.

A Canker Barking at the Wrong Knee: Thyronectria austroamericana Septic Arthritis

The mold Thyronectria austroamericana is a plant pathogen that causes canker in honey locust trees. We describe the first case of this mold causing septic arthritis in humans.

Case of femoral pseudarthrosis due to Scedosporium apiospermum in an immunocompetent patient with successful conservative treatment and review of literature

Scedosporium apiospermum is a ubiquitous filamentous fungus, commonly found in soil, sewage and polluted waters. It is rarely pathogenic but can cause a broad spectrum of clinical diseases, which can be localised or disseminate to distant organs. The disseminated form of the disease is mostly seen among immunocompromised patients. However, some rare cases of disseminated disease have been reported in immunocompetent individuals. Treatment of these infections is challenging because of their natural resistance to many antifungal agents. Here, we report the case of a 57-year-old immunocompetent patient diagnosed with femoral pseudarthrosis due to S. apiospermum, despite having no obvious clinical sign of infection. Previously, the patient had undergone four iterative femoral surgeries following a road traffic accident which occurred 20 years before. During its last surgery for pseudarthrosis, no clinical or biological signs of infection were present. Per operative samples tested positive for S. apiospermum. The patient was successfully treated with oral voriconazole during 6 months with an excellent tolerance. We also provide a review of literature on bone and joint infections due to Scedosporium spp. (S. apiospermum, Scedosporium boydii and Scedosporium aurantiacum), discussing the evolution of their management and outcome which seems to improve since the use of voriconazole.

A cluster of scedosporiosis in lung transplant candidates and recipients: The Zurich experience and review of the literature

Scedosporium species are fungal pathogens increasingly recognized in cystic fibrosis (CF). They can cause multiresistant, life-threatening infections that are of particular concern in CF patients undergoing lung transplantation, as optimal treatment remains unclear. Here, we describe our Zurich experience of CF patients with Scedosporium infection. Disseminated infection occurred in one patient after transplantation and was successfully treated. We propose a step-by-step approach to treat candidates with colonization, and discuss our cases in the context of the current literature.

Osteoarticular Infections Caused by Non-Aspergillus Filamentous Fungi in Adult and Pediatric Patients: A Systematic Review

Osteoarticular mycoses due to non-Aspergillus moulds are uncommon and challenging infections. A systematic literature review of non-Aspergillus osteoarticular mycoses was performed using PUBMED and EMBASE databases from 1970 to 2013. Among 145 patients were 111 adults (median age 48.5 [16-92 y]) and 34 pediatric patients (median age 7.5 [3-15 y]); 114 (79.7%) were male and 88 (61.9%) were immunocompromised. Osteomyelitis was due to direct inoculation in 54.5%. Trauma and puncture wounds were more frequent in children (73.5% vs 43.5%; P = 0.001). Prior surgery was more frequent in adults (27.7% vs 5.9%; P = 0.025). Vertebral (23.2%) and craniofacial osteomyelitis (13.1%) with neurological deficits predominated in adults. Lower limb osteomyelitis (47.7%) and knee arthritis (67.8%) were predominantly seen in children. Hyalohyphomycosis represented 64.8% of documented infections with Scedosporium apiospermum (33.1%) and Lomentospora prolificans (15.8%) as the most common causes. Combined antifungal therapy and surgery was used in 69% of cases with overall response in 85.8%. Median duration of therapy was 115 days (range 5-730). When voriconazole was used as single agent for treatment of hyalohyphomycosis and phaeohyphomycosis, an overall response rate was achieved in 94.1% of cases. Non-Aspergillus osteoarticular mycoses occur most frequently in children after injury and in adults after surgery. Accurate early diagnosis and long-course therapy (median 6 mo) with a combined medical-surgical approach may result in favorable outcome.

Combination Antifungal Therapy in the Treatment of Scedosporium apiospermum Central Nervous System Infections

Treatment of Scedosporium apiospermum central nervous system (CNS) infection typically consists of an azole in combination with surgical debridement. This approach requires prolonged treatment and carries a high associated mortality. We present two cases of the successful treatment of S. apiospermum CNS infections with the combination of voriconazole and terbinafine.

Severe filamentous fungal infections after widespread tissue damage due to traumatic injury: six cases and review of the literature

We describe 6 cases of severe filamentous fungal infections after widespread tissue damage due to traumatic injury in previously healthy people. Additionally, we report 69 cases from an exhaustive 20-y review of the literature to investigate the epidemiological and clinical features, the prognosis and the therapeutic management of these post-traumatic severe filamentous fungal infections. Traffic (41%) and farm accidents (25%) were the main causes of injury, which involved either the limbs only (41%) or multiple sites (41%). Necrosis was the main symptom (60%) and Mucorales (72%) and Aspergillus (11%) were the 2 most frequent fungi causing infection. These infections required substantial surgical debridement or amputation (96%) associated with aggressive antifungal therapy (81%), depending on the responsible fungi. This study underlines the need for early, repeated and systematic mycological wound samples to guide and adapt surgical and antifungal management in these filamentous fungal infections.

Infections caused by Scedosporium spp

Scedosporium spp. are increasingly recognized as causes of resistant life-threatening infections in immunocompromised patients. Scedosporium spp. also cause a wide spectrum of conditions, including mycetoma, saprobic involvement and colonization of the airways, sinopulmonary infections, extrapulmonary localized infections, and disseminated infections. Invasive scedosporium infections are also associated with central nervous infection following near-drowning accidents. The most common sites of infection are the lungs, sinuses, bones, joints, eyes, and brain. Scedosporium apiospermum and Scedosporium prolificans are the two principal medically important species of this genus. Pseudallescheria boydii, the teleomorph of S. apiospermum, is recognized by the presence of cleistothecia. Recent advances in molecular taxonomy have advanced the understanding of the genus Scedosporium and have demonstrated a wider range of species than heretofore recognized. Studies of the pathogenesis of and immune response to Scedosporium spp. underscore the importance of innate host defenses in protection against these organisms. Microbiological diagnosis of Scedosporium spp. currently depends upon culture and morphological characterization. Molecular tools for clinical microbiological detection of Scedosporium spp. are currently investigational. Infections caused by S. apiospermum and P. boydii in patients and animals may respond to antifungal triazoles. By comparison, infections caused by S. prolificans seldom respond to medical therapy alone. Surgery and reversal of immunosuppression may be the only effective therapeutic options for infections caused by S. prolificans.

Infection with Scedosporium apiospermum and S. prolificans, Australia

S. prolificans has become a major pathogen in immunocompromised patients.

Scedosporium apiospermum and S. prolificans are fungi of increasing clinical importance, particularly in persons with underlying diseases. We reviewed the records of 59 patients in Australia from whom Scedosporium spp. were isolated from June 30, 1997, through December 31, 2003. S. apiospermum was isolated predominantly from the respiratory tracts of 28 of 31 patients with underlying lung diseases and resulted in 2 infections and 1 death. The annual number of S. apiospermum isolates remained constant. S. prolificans was isolated from 28 patients only after November 1999. Eight patients with acute myeloid leukemia or hematopoietic stem cell transplants had invasive infection; 4 had fungemia and 6 died from infection. S. prolificans caused locally invasive infection in 2 immunocompetent patients and was found in the respiratory tract of 18 patients with underlying respiratory disease but did not cause fungemia or deaths in these patients. Scedosporium spp. showed distinct clinical and epidemiologic features.

Pseudallescheriasis in the 21st century

Since its discovery as an agent of mycetoma nearly a century ago, Pseudallescheria boydii with its asexual (synanamorphic) form, Scedosporium apiospermum, is now recognized as an important emerging opportunistic pathogen causing invasive mycosis in immunocompromised patients. The clinical spectrum of pseudallescheriasis is wide. Invasive disease of the lung, CNS and dissemination are serious manifestations in immunocompromised patients. This organism responds poorly to amphotericin B, and its histopathologic resemblance to aspergillosis often results in a delay in diagnosis. In vitro data, animal models and accumulating clinical experience support the use of voriconazole as a primary treatment for pseudallescheriasis. This paper reviews the microbiology, ecology, epidemiologic trends, clinical manifestations and current treatment options of pseudallescheriasis.

Scedosporium apiospermum mycetoma with bone involvement successfully treated with voriconazole

Treatment of Scedosporium apiospermum mycetoma usually requires limb amputation. A 49-year-old woman, from Ivory Coast, was diagnosed with Madura foot in 1995. She failed to respond to several treatments including itraconazole, fluconazole and co-trimoxazole, and refused limb amputation. In December 2002 she was admitted to hospital in France with a painful, swollen right leg and foot. She had no fever and C-reactive protein was 120 mg/l. Magnetic resonance imaging (MRI) confirmed the destruction of tarsus bones with a tibia extension. Voriconazole (400 mg/day) treatment was initiated in March 2003; a significant clinical improvement was observed within 4 months as confirmed by C-reactive protein (16 mg/l) and MRI. Voriconazole was maintained for 18 months with good tolerance. Cholestasis appeared after the first month and remained stable. In October 2004 voriconazole was discontinued due to side effects on the liver (alanine aminotransferase 17 times the normal level); MRI showed impressive regression of bone lesions. As of July 2005, the patient remains clinically well. Voriconazole appears to be a promising drug for the treatment of S. apiospermum mycetomas.

Infections Due to Scedosporium apiospermum and Scedosporium prolificans in Transplant Recipients: Clinical Characteristics and Impact of Antifungal Agent Therapy on Outcome

BACKGROUND

Unique characteristics, impact of therapy with antifungal agents, and outcome of infections with Scedosporium species were assessed in transplant recipients.

METHODS

The patients comprised a total of 80 transplant recipients with Scedosporium infections, including 13 patients from our institutions (University of Pittsburgh Medical Center [Pittsburgh, PA], University of Maryland [Baltimore], Duke University Medical Center [Durham, NC], Emory University [Atlanta, GA], and Hospital Gregorio Maranon [Madrid, Spain]) and 67 reported in the literature. The transplant recipients were compared with 190 non-transplant recipients with scedosporiosis who were described in the literature.

RESULTS

Overall, 69% of the infections in hematopoietic stem cell transplant (HSCT) recipients and 53% of the infections in organ transplant recipients were disseminated. HSCT recipients, compared with organ transplant recipients, were more likely to have infections caused by Scedosporium prolificans (P=.045), to have an earlier onset of infection (P=.007), to be neutropenic (P<.0001), and to have fungemia (P=.04). Time elapsed from transplantation to Scedosporium infection in transplant recipients has increased in recent years (P=.002). The mortality rate among transplant recipients with scedosporiosis was 58%. In a logistic regression model using amphotericin B as comparison treatment, voriconazole was associated with a trend towards better survival (odds ratio [OR], 10.40; P=.08). Presence of disseminated infection (OR, 0.20; P=.03) predicted lower survival, and receipt of adjunctive surgery as treatment (OR, 5.52; P=.02) independently predicted a better survival in this model.

CONCLUSIONS

Scedosporium infections in transplant recipients were associated with a high rate of dissemination and a poor outcome overall. The use of newer triazole agents warrants consideration as a therapeutic modality for these infections.

Invasive infections caused by Blastoschizomyces capitatus and Scedosporium spp

Blastoschizomyces capitatus, Scedosporium prolificans and S. apiospermum are emerging fungal pathogens that may cause disseminated disease in neutropenic patients. They can present as fever resistant to antibiotics and to wide-spectrum antifungal agents, although they may involve almost every organ. The proportion of recovery from blood cultures is high and they are characteristically resistant to most antifungal agents. Prognosis is poor unless patients recover from neutropenia. Voriconazole has good in-vitro activity and is currently the drug of choice for these infections.

Mycotic osteomyelitis due to Scedosporium Apiospermum: MR imaging-pathologic correlation

Mycotic osteomyelitis is rare and occurs in immunocompromised patients after inoculation of the pathogen at a penetrating trauma site. Mycotic osteomyelitis due to Scedosporium Apiospermum is extremely rare, with only 13 cases of septic arthritis reported previously. Ours is only the third case of S. apiospermum osteomyelitis in an immunocompromised patient and the only patient with a histopathologic diagnosis from an amputation specimen. Recognition of this pathogen may be delayed due to insidious onset and negative joint fluid cultures, often requiring synovial or bone biopsies to establish the diagnosis. Delay in appropriate treatment may result in disseminating infection or even death.

Scedosporium prolificans osteomyelitis in an immunocompetent child treated with voriconazole and caspofungin, as well as locally applied polyhexamethylene biguanide

Scedosporium species are increasingly isolated from immunocompromised and immunocompetent patients. Unfortunately, Scedosporium infections are generally resistant to amphotericin B, and Scedosporium prolificans strains are particularly resistant to the antifungal agents now in use. We report here on an immunocompetent child with S. prolificans-associated osteomyelitis successfully treated with debridement, local irrigation with polyhexamethylene biguanide, and the systemic administration of voriconazole and caspofungin despite poor in vitro activity of voriconazole alone against the isolate. We also review the treatments and outcomes of 28 reported cases of osteomyelitis or septic arthritis caused by Scedosporium species in immunocompetent patients.

Disseminated infection due to Scedosporium apiospermum in a patient with acute myelogenous leukemia

A 62-year-old man diagnosed with acute myelogenous leukemia which had developed from myelodysplastic syndrome received cytarabine and idarubicine as an induction therapy. The patient developed pneumonia and bacterial sepsis during profound neutropenia. Fever and sepsis improved by using many anti-bacterials and anti-fungals but he became febrile again and complained of severe lumbar pain. 67Ga scintigram showed abnormal uptake in the lumbar vertebra and left sternoclavicular joint, suggesting a diagnosis of discitis and osteomyelitis in the lumbar vertebra and sternoclavicular arthritis. We biopsied the site several times but culture of the biopsy specimen could not isolate any pathogens, and high fever persisted for about 10 months despite administration of various anti-bacterials and anti-fungals. Finally we inserted a catheter into the abscess at the iliopsoas muscle and Scedosporium apiospermum was isolated in the bloody pus obtained from the catheter. Itraconazole and amphotericin B were restarted, and the high fever and lumbar pain improved rapidly. The findings of S. apiospermum infection in this patient emphasizes the importance of being aware of this pathogen in patients with hematologic malignancy during the neutropenic phase.

Antifungal pharmacotherapy for invasive mould infections

The incidence of invasive mould infections is increasing and is associated with significant morbidity and mortality. Among the most prevalent of these infections are those caused by Aspergillus and Fusarium species. Invasive disease caused by moulds frequently presents as a pulmonary infection, but haematogenous infection can occur. Some moulds cause cutaneous disease through either direct inoculation of the skin or secondary spread to the skin after dissemination from another body site. Early diagnosis can often be difficult and, unfortunately, diagnosis occurs late in the course of illness in many cases. Treatment options have historically been limited by the need for intravenous administration (amphotericin B), significant toxicities (amphotericin B), lack of reliable in vitro activity (e.g., amphotericin B in Fusarium and Scedosporium apiospermum infections) and relative lack of clinical experience with newer agents. The recent approval of voriconazole (Vfend, Pfizer) introduces a treatment option that demonstrates both in vitro and in vivo activity against a variety of moulds. With the recent development of the new echinocandin class of antifungal agents and newer broad-spectrum azole antifungal agents with in vitro mould activity, there is a renewed emphasis on fungal treatment strategies. Antimould therapy presents challenges in adverse effect avoidance and management, drug interactions and pharmacoeconomic considerations. Furthermore, combination therapy is being explored with these various new antifungal agents. The administration of an optimal fungicidal therapy early in the course of the illness and control of the underlying disease are vital to prevent complications and mortality from these tenacious mycoses.