Emerging fungal infections in solid organ transplant recipients

The effect of infectious diseases on lung transplantation in Japan

Lung transplantation in Japan is an increasingly accessible treatment option for end-stage lung disease; however, the lack of donor organs is a persisting challenge. Five- and 10-year survival rates of lung transplant recipients in Japan are comparable, if not superior, to international standards. The outcomes of lung transplantation in Japan are likely affected by multiple factors. Infectious disease complications are a significant burden to transplant recipients and account for approximately 30% of recipient mortality in Japan, presenting a major challenge in peri-transplant management. Herein, we explore the current status of infectious disease epidemiology, available evidence surrounding infectious diseases in lung transplantation, and potentially influential factors pertinent to lung transplantation outcomes in Japan. Although infection remains the major cause of morbidity and mortality associated with lung transplantation in Japan, there is limited data and evidence. Despite some uncertainties, publicly available data suggests a low rate of antimicrobial resistance in Gram-negative bacteria and a distinct set of endemic pathogens that recipients may encounter. As a countermeasure against the burden of infectious diseases, 8 out of 10 transplant centers in Japan have a dedicated infectious diseases department. Despite these efforts, specific surveillance, prevention, and management are indispensable to improving post-transplantation infectious disease management. We accordingly lay out potential areas for improving infectious disease-related outcomes among lung transplant recipients in Japan.

Trichoderma spp.-Related Pneumonia: A Case Report in Heart-Lung Transplantation Recipient and a Systematic Literature Review

Opportunistic and hospital-acquired infections are common among recipients of solid organ transplantation. New pathogens are increasingly reported in the intensive care unit (ICU) population. We report a case of a patient who developed Trichoderma spp.-related pneumonia (TRP) after heart-lung transplantation. In the absence of antifungal susceptibility testing, TRP was confirmed by histological examination, and empirical therapy with voriconazole and caspofungin was swiftly initiated. Complete resolution of pneumonia was obtained after prolonged combination therapy. Given the lack of guidelines, we conducted a systematic review to elucidate the diagnostic and therapeutic strategies to apply during Trichoderma infection. After deduplication and selection of full texts, we found 42 articles eligible for the systematic review. Pneumonia seems to be the most common clinical manifestation (31.8%). The most used antifungal therapy was amphotericin B, while combination therapy was also reported (27.3%). All the patients were immunocompromised except for one case. Despite the rarity of Trichoderma spp. infection, the increase in invasive fungal infections is of growing importance in ICU, considering their impact on mortality and the emergence of antifungal resistance. In the absence of prospective and multicenter studies, a review can provide useful insight regarding the epidemiology, clinical manifestations, and management of these unexpected challenges.

Scedosporium and Lomentospora Infections Are Infrequent, Difficult to Diagnose by Histology, and Highly Virulent

OBJECTIVE

To further characterize the histomorphology and clinicopathologic features of colonization and invasive disease by Scedosporium and Lomentospora.

METHODS

We conducted a 20-year retrospective study. Patients with at least 1 histopathology specimen and concurrent culture were included. Clinical features, histopathology, microbiology, and outcomes were analyzed.

RESULTS

Eighteen patients were identified, and all were immunocompromised. Eight patients had colonization, while 10 had invasive disease (pneumonia [n = 3], skin and soft-tissue infections [n = 3], disseminated disease [n = 4]). Scedosporium apiospermum was identified in 15 patients, Lomentospora prolificans in 2 patients, and Scedosporium ellipsoideum in 1 patient. Fungal elements were identified histologically in 11 patients. Granulomatous, suppurative, and necrotizing inflammation with irregular branching hyphae and characteristic microconidia were observed in 9 cases; conidiogenous cells were identified in 4 cases. Seven patients died of invasive disease despite therapy, and 3 recovered after treatment. No deaths were observed in patients with colonization.

CONCLUSIONS

Scedosporium and Lomentospora are rare, virulent opportunistic fungal pathogens. Fungal morphology may overlap with other hyaline molds, but identification of obovoid conidia should allow a diagnosis of non-Aspergillus hyalohyphomycosis and consideration of Scedosporium and Lomentospora. Histopathologic correlation with culture and polymerase chain reaction is critical for diagnosis and treatment.

Emerging Fungal Infections

Various uncommon fungal pathogens have been increasingly identified as causes of disseminated and invasive fungal disease (IFD) worldwide. Growing recognition and clinical knowledge of these emerging fungal pathogens has occurred through improved molecular diagnostics, nucleic sequence databases, and taxonomic reclassification of medically significant fungi. However, emerging fungal diseases carry significant morbidity and mortality and, due to a paucity of published literature, the collective clinical experience with these fungi is often limited. In this review, we focus on unusual emerging fungal pathogens not extensively covered elsewhere in this issue of Infectious Diseases Clinics of North America.

Pneumonia With Scedosporium apiospermum and Lomentospora prolificans in a Patient After Bilateral Lung Transplantation for Pulmonary Hypertension: A Case Report

Infections caused by the Scedosporium genus have become recognized as a fatal complication after lung transplantation in Europe and Australia, but the reports have been rare from Asian countries including Japan. We present a case of pneumonia caused by a mixed infection of Scedosporium apiospermum (SA) and Lomentospora prolificans (LP) that developed after augmentation of immunosuppression for chronic lung allograft dysfunction (CLAD) after lung transplantation. A 13-year-old man underwent bilateral lung transplantation for pulmonary hypertension. One year after surgery, he was treated with a series of augmented immunosuppressive therapy for severe acute rejection and subsequent CLAD. Three months following the first steroid pulse therapy, his serum β-D-glucan elevated without any sign of fungal infection by other tests. The serum β-D-glucan once returned to a normal level by empirical administration of micafungin; however, the patient's condition worsened again by discontinuation of it. He did not recover by restarting micafungin, and computed tomography (CT) scans eventually demonstrated new infiltrates in his lung field 6 weeks after the elevation of serum β-D-glucan. Microscopic findings of transbronchial lung biopsy specimens showed filamentous fungi, and the culture of bronchoalveolar lavage fluid revealed the growth of SA and LP. Despite subsequent voriconazole administration, he died 14 days after the start of voriconazole. Early and aggressive inspection including bronchoscopy should be performed for the diagnosis of Scedosporium infection in immunocompromised patients, even if CT scans and sputum culture show no evidence of infection.

Evaluation of ID Fungi Plates Medium for Identification of Molds by MALDI Biotyper

MALDI-TOF mass spectrometry (MS) identification of pathogenic filamentous fungi is often impaired by difficulties in harvesting hyphae embedded in the medium and long extraction protocols. The ID Fungi Plate (IDFP) is a novel culture method developed to address such difficulties and improve the identification of filamentous fungi by MALDI-TOF MS. We cultured 64 strains and 11 clinical samples on IDFP, Sabouraud agar-chloramphenicol (SAB), and ChromID Candida agar (CAN2). We then compared the three media for growth, ease of harvest, amount of material picked, and MALDI-TOF identification scores after either rapid direct transfer (DT) or a long ethanol-acetonitrile (EA) extraction protocol. Antifungal susceptibility testing and microscopic morphology after subculture on SAB and IDFP were also compared for ten molds. Growth rates and morphological aspects were similar for the three media. With IDFP, harvesting of fungal material for the extraction procedure was rapid and easy in 92.4% of cases, whereas it was tedious on SAB or CAN2 in 65.2% and 80.3% of cases, respectively. The proportion of scores above 1.7 (defined as acceptable identification) were comparable for both extraction protocols using IDFP (P = 0.256). Moreover, rates of acceptable identification after DT performed on IDFP (93.9%) were significantly higher than those obtained after EA extraction with SAB (69.7%) or CAN2 (71.2%) (P = <0.001 and P = 0.001, respectively). Morphological aspects and antifungal susceptibility testing were similar between IDFP and SAB. IDFP is a culture plate that facilitates and improves the identification of filamentous fungi, allowing accurate routine identification of molds with MALDI-TOF-MS using a rapid-extraction protocol.

Infection prophylaxis and management of fungal infections in lung transplant

Lung transplantation has emerged as a lifesaving treatment for a wide range of advanced lung diseases. While the survival of lung transplant recipients continues to improve, infectious complications contribute substantially to morbidity and mortality following lung transplantation. The incidence of invasive fungal infections is variable, with a mean occurrence of 8.6%. The majority of fungal infections in lung transplant recipients are caused Aspergillus and Candida species. This review provides an update in the current approaches for the diagnosis, management and prevention of fungal infections and the late complications that are associated.

Fungal evolution: major ecological adaptations and evolutionary transitions

Fungi are a highly diverse group of heterotrophic eukaryotes characterized by the absence of phagotrophy and the presence of a chitinous cell wall. While unicellular fungi are far from rare, part of the evolutionary success of the group resides in their ability to grow indefinitely as a cylindrical multinucleated cell (hypha). Armed with these morphological traits and with an extremely high metabolical diversity, fungi have conquered numerous ecological niches and have shaped a whole world of interactions with other living organisms. Herein we survey the main evolutionary and ecological processes that have guided fungal diversity. We will first review the ecology and evolution of the zoosporic lineages and the process of terrestrialization, as one of the major evolutionary transitions in this kingdom. Several plausible scenarios have been proposed for fungal terrestralization and we here propose a new scenario, which considers icy environments as a transitory niche between water and emerged land. We then focus on exploring the main ecological relationships of Fungi with other organisms (other fungi, protozoans, animals and plants), as well as the origin of adaptations to certain specialized ecological niches within the group (lichens, black fungi and yeasts). Throughout this review we use an evolutionary and comparative-genomics perspective to understand fungal ecological diversity. Finally, we highlight the importance of genome-enabled inferences to envision plausible narratives and scenarios for important transitions.

Brain abscess caused by Cladophialophora bantiana after renal allograft loss: A case report

Cerebral feohifomycosis are severe infections caused by dematiaceous fungi. Cladophialophora bantiana is one of the most commonly isolated species; it has central nervous system tropism and it often manifests as a brain abscess in immunocompetent patients. In immunocompromised patients, it can lead to brain abscesses and disseminated infections. Despite the availability of broad-spectrum antifungal drugs, it is a must to perform surgical management, in addition to drug therapy. However, mortality is high. The diagnostic approach must be invasive to establish a timely diagnosis and direct treatment based on culture and susceptibility tests. We report a case of brain abscess caused by C. bantiana in an immunosuppressed patient who was treated with surgical resection and voriconazole with an adequate response to therapy and without neurological sequels.

Mold Infections in Solid Organ Transplant Recipients

Mold infections carry a substantial clinical and economic burden in solid organ transplant (SOT) recipients with a high overall mortality of near 30%. The most important pathogens include Aspergillus, the Zygomycetes, Fusarium, Scedosporium/Pseudallescheria, and the dematiaceous (dark) molds. Risk factors for the infections vary by transplant type but include degree of immune suppression and loss of skin or mucosal integrity. Correct diagnosis usually requires histopathology and/or culture. Management often requires a multidisciplinary team approach with combined antifungal and surgical therapies. This article reviews the epidemiology, risk factors, microbiology, diagnostic, and treatment approach to mold infections in SOT recipients.

Molecular Identification and Susceptibility Testing of Molds Isolated in a Prospective Surveillance of Triazole Resistance in Spain (FILPOP2 Study)

Antifungal resistance is increasing by the emergence of intrinsically resistant species and by the development of secondary resistance in susceptible species. A previous study performed in Spain revealed levels of azole resistance in molds of between 10 and 12.7%, but secondary resistance in Aspergillus fumigatus was not detected. We used itraconazole (ITZ)-supplemented medium to select resistant strains. A total of 500 plates supplemented with 2 mg/liter of ITZ were sent to 10 Spanish tertiary hospitals, and molecular identification and antifungal susceptibility testing were performed. In addition, the cyp51A gene in those A. fumigatus strains showing azole resistance was sequenced. A total of 493 isolates were included in the study. Sixteen strains were isolated from patients with an infection classified as proven, 104 were isolated from patients with an infection classified as probable, and 373 were isolated from patients with an infection classified as colonization. Aspergillus was the most frequent genus isolated, at 80.3%, followed by Scedosporium-Lomentospora (7.9%), Penicillium-Talaromyces (4.5%), Fusarium (2.6%), and the order Mucorales (1%). Antifungal resistance was detected in Scedosporium-Lomentospora species, Fusarium, Talaromyces, and Mucorales Three strains of A. fumigatus sensu stricto were resistant to azoles; two of them harbored the TR₃₄+L98H mechanism of resistance, and the other one had no mutations in cyp51A The level of azole resistance in A. fumigatus remains low, but cryptic species represent over 10% of the isolates and have a broader but overall higher range of antifungal resistance.

Transplant tourism and invasive fungal infection

BACKGROUND

Deceased and live-related renal transplants (RTXs) are approved procedures that are performed widely throughout the world. In certain regions, commercial RTX has become popular, driven by financial greed.

METHODS

This retrospective, descriptive study was performed at the Royal Hospital from 2013 to 2015. Data were collected from the national kidney transplant registry of Oman. All transplant cases retrieved were divided into two groups: live-related RTX performed in Oman and commercial-unrelated RTX performed abroad. These groups were then divided again into those with and without evidence of fungal infection, either in the wound or renal graft.

RESULTS

A total of 198 RTX patients were identified, of whom 162 (81.8%) had undergone a commercial RTX that was done abroad. Invasive fungal infections (IFIs) were diagnosed in 8% of patients who had undergone a commercial RTX; of these patients, 76.9% underwent a nephrectomy and 23.1% continued with a functioning graft. None of the patients with RTXs performed at the Royal Hospital contracted an IFI. The most common fungal isolates were Aspergillus species (including Aspergillus flavus, Aspergillus fumigatus, Aspergillus nidulans, and Aspergillus nigricans), followed by Zygomycetes. However, there was no evidence of fungal infection including Aspergillus outside the graft site. Computed tomography (CT) findings showed infarction of the graft, renal artery thrombosis, aneurysmal dilatation of the external iliac artery, fungal ball, or just the presence of a perigraft collection. Of the total patients with IFIs, 23.1% died due to septic shock and 53.8% were alive and on hemodialysis. The remaining 23.1% who did not undergo nephrectomy demonstrated acceptable graft function.

CONCLUSIONS

This is the largest single-center study on commercial RTX reporting the highest number of patients with IFI acquired over a relatively short period of time. Aspergillus spp were the main culprit fungi, with no Candida spp being isolated. A high index of suspicion might be the most reasonable means to reduce the possible very poor outcomes. Improving legal transplant programs and strengthening the associated laws could prevent commercial transplant tourism.

Single-center experience of antifungal prophylaxis for coccidioidomycosis in heart transplant recipients within an endemic area

In endemic regions, coccidioidomycosis causes substantial morbidity and mortality for patients receiving solid organ transplants. We aimed to demonstrate the effect of antifungal coccidioidal prophylaxis in heart transplant (HT) recipients. We retrospectively reviewed the electronic health records of all patients who received HTs between October 19, 2005, and December 13, 2014. We collected information regarding antifungal regimens and determined whether patients subsequently developed infections. Our 174-person cohort all received antifungal prophylaxis for at least 6 months (mean follow-up, 53.8 months). One proven and one probable coccidioidal infection (each, 0.6%) occurred during the study period. The incidence of coccidioidomycosis was 0.6% at 1 year and 2.3% at 5 years. No cases of proven coccidioidomycosis occurred within 2 years after transplantation. No patients developed disseminated disease, and no sentinel events were attributed to coccidioidomycosis. Both fluconazole and voriconazole were well tolerated. In the absence of intolerance or contraindication, we suggest continuing a universal antifungal prophylactic regimen with fluconazole for at least 6-12 months in HT recipients residing in a coccidioidomycosis-endemic area.

Systemic Scedosporium prolificans infection in an 11-month-old Border collie with cobalamin deficiency secondary to selective cobalamin malabsorption (canine Imerslund-Gräsbeck syndrome)

An 11-month-old Border collie presented collapsed and continued to deteriorate rapidly despite supportive treatment. The dog had a history of failure to thrive and recurring respiratory infection. Laboratory abnormalities included neutrophilic leucocytosis, Heinz body anaemia, hyperammonaemia, hyperbilirubinaemia, proteinuria and hypocobalaminaemia. Post-mortem examination revealed multi-focal necrosis within the heart, kidneys, pancreas, liver, meninges and cerebral cortex. Fungal hyphae in lesions were identified as Scedosporium prolificans following culture. Subsequent genotyping confirmed that the dog carried the CUBN:c.8392delC mutation in a homozygous state, verifying hereditary cobalamin deficiency (a.k.a. Imerslund-Gräsbeck syndrome). Cobalamin deficiency may have been a predisposing factor for the development of systemic fungal infection in this dog.

Scolecobasidium granulomatous pneumonia and abscess - an emerging opportunistic fungal pathogen: a case report

Scolecobasidium sp. are commensal soil and water thermophilic dematiaceous fungi. They are commonly isolated as contaminants from respiratory secretions due to their abundant presence in water supplies, but they are also rare yet emerging culprits producing severe opportunistic infections in immunocompromised individuals. The most consistent presentations reported in literature are life-threatening pulmonary and cerebral granulomatous lesions.

The neurology of solid organ transplantation

Transplantation is the rescue treatment for end-stage organ failure with more than 110,000 solid organs transplantations performed worldwide annually. Recent advances in transplantation procedures and posttransplantation management have improved long-term survival and quality of life of transplant recipients, shifting the focus from acute perioperative critical care needs toward long-term chronic medical problems. Neurologic complications affect up to 30-60 % of solid organ transplant recipients. Common etiologies include opportunistic infections and toxicities of antirejection medications, and wide spectrum of toxic and metabolic disturbances. Most complications are common to all allograft types, but some are relatively specific for individual allograft types (e.g., central pontine myelinolysis in liver transplant recipients). Close collaboration between neurologists and other transplant team members is essential for effective management. Early recognition of complications and accurate diagnosis leading to timely treatment is essential to reduce the morbidity and improve the overall transplant outcome.

Phaeohyphomycosis in Transplant Patients

Phaeohyphomycosis is caused by a large, heterogenous group of darkly pigmented fungi. The presence of melanin in their cell walls is characteristic, and is likely an important virulence factor. These infections are being increasingly seen in a variety of clinical syndromes in both immunocompromised and normal individuals. Transplant patients are especially at risk due their prolonged immunosuppression. There are no specific diagnostic tests for these fungi, though the Fontana-Masson stain is relatively specific in tissue. They are generally seen in a worldwide distribution, though a few species are only found in specific geographic regions. Management of these infections is not standardized due to lack of clinical trials, though recommendations are available based on clinical experience from case reports and series and animal models. Superficial infections may be treated without systemic therapy. Central nervous system infections are unique in that they often affect otherwise normal individuals, and are difficult to treat. Disseminated infections carry a high mortality despite aggressive therapy, usually with multiple antifungal drugs. Considerable work is needed to determine optimal diagnostic and treatment strategies for these infections.

Emerging issues with diagnosis and management of fungal infections in solid organ transplant recipients

Invasive fungal infections (IFIs) are being increasingly recognized in solid organ transplant (SOT) recipients, and delayed diagnosis can lead to graft loss and death. Therefore, there is a low threshold for prophylaxis and early initiation of empiric antifungal treatment, in this patient population. Meanwhile, the increasing consumption of antifungals is associated with high cost, medication toxicities and the emergence of resistance in Candida species, all of which call for rational use of antifungal agents. The implementation of fungal biomarkers, molecular diagnostic methods and direct detection of volatile fungal metabolites in breath samples could lead to faster diagnosis, early appropriate treatment and improved clinical outcomes, but also aid in the de-escalation of antifungal treatment. Those novel diagnostic modalities need to be validated specifically in SOT recipients. Infectious diseases consultation can contribute to optimization of care through prompt initiation and appropriate modification of antifungal treatment, management of medication toxicities and drug-drug interactions, as well as source control. In this review, we conceptually summarize recent advances in the diagnosis and management of IFI in SOT recipients, and highlight the importance of early diagnostic tools and good stewardship of antifungal drugs.

Successful long-term management of invasive cerebral fungal infection following liver transplantation

Central nervous system (CNS) infections after liver transplantation may be fungal in aetiology, with involvement from either common organisms such as Cryptococcus neoformans and Aspergillus spp. as well as less common organisms, such as the Mucorales and Scedosporium spp. Although the mortality of CNS fungal infections was nearly 100% in early series, more recent data has suggested that good outcomes can be achieved. This may be due to both improved diagnostic capabilities, such as the ability to obtain fungal susceptibilities and therapeutic drug levels, and improved therapeutic options, such as the newer triazoles- voriconazole and posaconazole. Due to improved outcomes, issues have now arisen around the long-term tolerability of these agents. The following two cases of invasive cerebral fungal infections following liver transplantation, one with Aspergillus flavus, and the other with Scedosporium boydii/apiospermum highlight the success that can be seen with the modern management of a previously fatal diagnosis. In particular, we highlight the issues around therapeutic monitoring and discontinuation of therapy.

A rare fungal species, Quambalaria cyanescens, isolated from a patient after augmentation mammoplasty--environmental contaminant or pathogen?

Some emerging but less common human fungal pathogens are known environmental species and could be of low virulence. Meanwhile, some species have natural antifungal drug resistance, which may pose significant clinical diagnosis and treatment challenges. Implant breast augmentation is one of the most frequently performed surgical procedures in China, and fungal infection of breast implants is considered rare. Here we report the isolation of a rare human fungal species, Quambalaria cyanescens, from a female patient in China. The patient had undergone bilateral augmentation mammoplasty 11 years ago and was admitted to Peking Union Medical College Hospital on 15 September 2011 with primary diagnosis of breast infection. She underwent surgery to remove the implant and fully recovered thereafter. During surgery, implants and surrounding tissues were removed and sent for histopathology and microbiology examination. Our careful review showed that there was no solid histopathologic evidence of infection apart from inflammation. However, a fungal strain, which was initially misidentified as “Candida tropicalis” because of the similar appearance on CHROMagar Candida, was recovered. The organism was later on re-identified as Q. cyanescens, based on sequencing of the rDNA internal transcribed spacer region rather than the D1/D2 domain of 26S rDNA. It exhibited high MICs to 5-flucytosine and all echinocandins, but appeared more susceptible to amphotericin B and azoles tested. The possible pathogenic role of Q. cyanescens in breast implants is discussed in this case, and the increased potential for misidentification of the isolate is a cause for concern as it may lead to inappropriate antifungal treatment.

Pathogenesis and host defence against Mucorales: the role of cytokines and interaction with antifungal drugs

Innate immune response, including macrophages, neutrophils and dendritic cells and their respective receptors, plays an important role in host defences against Mucorales with differential activity against specific fungal species, while adaptive immunity is not the first line of defence. A number of endogenous and exogenous factors, such as cytokines and growth factors as well as certain antifungal agents have been found that they influence innate immune response to these organisms. Used alone or especially in combination have been shown to exert antifungal effects against Mucorales species. These findings suggest novel ways of adjunctive therapy for patients with invasive mucormycosis.

Posaconazole salvage treatment for invasive fungal infection

Invasive fungal infection (IFI) is an important cause of morbidity and mortality. Posaconazole is a second generation triazole with a broad spectrum, and it may be suitable for salvage antifungal treatment although posaconazole is not usually considered to be as first-line antifungal therapy for IFI. The purpose of this study was to assess the utility of posaconazole salvage treatment for IFI. We conducted a retrospective review of patients with salvage antifungal treatment with posaconazole for IFI at our institution between December 2007 and July 2012. A total of ten patients received posaconazole salvage IFI. Etiology of IFI was consisting of mucormycosis (four patients), Paecilomyces variotii (one patient), and unspecified IFI etiology (five patients). Causes of posaconazole treatment were following; intolerance of previous antifungal therapy in five patients, refractory IFI on previous antifungal therapy in four patients, and both intolerance of previous antifungal therapy and refractory IFI on previous antifungal therapy in one patient. Duration of posaconazole salvage treatment ranged from 15 to 355 days with median 47 days. The overall successful posaconazole salvage treatment response rate was 80.0 % (8 of 10 patients). There were three patients who died during the study period. However, only one death was attributed to the progression of IFI. Two patients discontinued posaconazole due to adverse events. Posaconazole salvage treatment was effective antifungal therapy for IFI. Further studies are needed to define the optimal therapeutic strategy.

Clinical and morphologic findings in disseminated Scedosporium apiospermum infections in immunocompromised patients

Scedosporium apiospermum is a ubiquitous, saprophytic, filamentous mold that may cause localized, subcutaneous infections in immunocompetent hosts, but disseminated infection in severely immunocompromised patients. This mold is often highly resistant to multiple commonly used antifungal drugs. Even with treatment, there is a high mortality rate. We present two patients with fatal disseminated S. apiospermum infections after bone marrow and lung transplantation. This infection can be rapidly fatal, and survival may be improved by early recognition.

Current status of antifungal resistance and its impact on clinical practice

Mortality linked to invasive fungal diseases remains very high despite the availability of novel antifungals and new therapeutic strategies. Candida albicans and Aspergillus fumigatus account for most invasive mycosis produced by yeast or moulds, respectively. Other Candida non-albicans are increasingly being reported and newly emerging, as well as cryptic, filamentous fungi often cause disseminated infections in immunocompromised hosts. Management of invasive fungal infections is becoming a challenge as emerging fungal pathogens generally show poor response to many antifungals. The ability of reference antifungal susceptibility testing methods to detect emerging resistance patterns, together with the molecular characterization of antifungal resistance mechanisms, are providing useful information to optimize the effectiveness of antifungal therapy. The current status of antifungal resistance epidemiology with special emphasis on the molecular resistant mechanisms that have been described in the main pathogenic fungal species are reviewed.

Invasive mold infections in solid organ transplant recipients

Invasive mold infections represent an increasing source of morbidity and mortality in solid organ transplant recipients. Whereas there is a large literature regarding invasive molds infections in hematopoietic stem cell transplants, data in solid organ transplants are scarcer. In this comprehensive review, we focused on invasive mold infection in the specific population of solid organ transplant. We highlighted epidemiology and specific risk factors for these infections and we assessed the main clinical and imaging findings by fungi and by type of solid organ transplant. Finally, we attempted to summarize the diagnostic strategy for detection of these fungi and tried to give an overview of the current prophylaxis treatments and outcomes of these infections in solid organ transplant recipients.