Morphologic criteria for the preliminary identification of Fusarium, Paecilomyces, and Acremonium species by histopathology

Hyphae, pseudohyphae, yeasts, spherules, spores, and more: A review on the morphology and pathology of fungal and oomycete infections in the skin of domestic animals

Fungi are among the most common infectious agents affecting the skin of animals. The skin can serve as a port of entry for fungal infections, which can eventually become disseminated. In some regions of the world, oomycetes, such as Pythium and Lagenidium, are also responsible for a significant number of severe cutaneous infections. Histologic evaluation of fungal morphology, including size, shape, septation, branching, and budding characteristics, combined with the distribution of inflammatory infiltrates within different skin layers can potentially identify etiologic agents, guiding selection of antifungals and additional diagnostics. Fungal infections of the skin surface are typically caused by Malassezia and rarely Candida, with opportunistic fungi also capable of colonizing the skin surface, especially when the barrier is broken. Folliculocentric infections, caused by dermatophytes, result in mild to severe inflammation and can occasionally penetrate deep into the skin. A wide range of fungi, including agents of hyalohyphomycosis, phaeohyphomycosis, and dimorphic fungal infections, as well as oomycetes, result in nodular cutaneous and subcutaneous lesions. With the occasional exception of dimorphic fungi, fungal speciation often requires cultures performed on fresh tissues. However, molecular techniques such as pan-fungal polymerase chain reaction on paraffin blocks is becoming an increasingly useful tool to distinguish between cutaneous fungal pathogens. This review focuses on describing the clinical and histologic features of the most common fungal and oomycete infections affecting the skin of animals, divided according to distribution patterns of lesions and fungal or oomycete morphology.

Non-Aspergillus Hyaline Molds: A Host-Based Perspective of Emerging Pathogenic Fungi Causing Sinopulmonary Diseases

The incidence of invasive sino-pulmonary diseases due to non-Aspergillus hyaline molds is increasing due to an enlarging and evolving population of immunosuppressed hosts as well as improvements in the capabilities of molecular-based diagnostics. Herein, we review the following opportunistic pathogens known to cause sinopulmonary disease, the most common manifestation of hyalohyphomycosis: Fusarium spp., Scedosporium spp., Lomentospora prolificans, Scopulariopsis spp., Trichoderma spp., Acremonium spp., Paecilomyces variotii, Purpureocillium lilacinum, Rasamsonia argillacea species complex, Arthrographis kalrae, and Penicillium species. To facilitate an understanding of the epidemiology and clinical features of sino-pulmonary hyalohyphomycoses in the context of host immune impairment, we utilized a host-based approach encompassing the following underlying conditions: neutropenia, hematologic malignancy, hematopoietic and solid organ transplantation, chronic granulomatous disease, acquired immunodeficiency syndrome, cystic fibrosis, and healthy individuals who sustain burns, trauma, or iatrogenic exposures. We further summarize the pre-clinical and clinical data informing antifungal management for each pathogen and consider the role of adjunctive surgery and/or immunomodulatory treatments to optimize patient outcome.

Coexistence of Fungal Keratitis in Bilateral Sequential Microsporidial Keratitis - A Rare Case Presentation

AIM

To report a case of bilateral microsporidiosis with coexisting fungal infection in one eye.

METHOD

Retrospective interventional case report.

RESULTS

A 61-year-old man with uncontrolled diabetes presented with clinical and microbiological features of non-resolving fungal keratitis in the right eye since 3 months and underwent therapeutic penetrating keratoplasty (TPK) for the same. Fungal filaments along with oval bodies suspicious of microconidia were noted on calcofluor stain. A week following TPK, the patient presented with features of viral keratouveitis in the left eye which on microbiology was confirmed as microsporidiosis. Retrospectively, the right eye microbiology slides were reassessed, which confirmed the coexistence of fungus with microsporidiosis by acid-fast stain and polymerase chain reaction.

CONCLUSION

Structural resemblance of microconidia with microsporidial spores can be misleading, thus creating a need for awareness regarding the possible coexistence along with a need to suspect microsporidiosis in nonresponding clinically resembling viral keratitis.

Implications of Crop Rotation and Fungicide on Fusarium and Mycotoxin Spectra in Manitoba Barley, 2017–2019

Fusarium head blight (FHB) is one of the most important diseases of barley in Manitoba province (western Canada), and other major barley producing regions of the world. Little is known about the Fusarium species and mycotoxin spectra associated with FHB of barley in Manitoba. Hence, barley grain samples were collected from 149 commercial fields from 2017 to 2019, along with information on respective cropping history, and analyzed with respect to Fusarium species spectra, abundance, chemotype composition, and mycotoxin profiles. Fusarium poae was the predominant Fusarium species associated with FHB of barley in Manitoba, followed by F. graminearum, and F. sporotrichioides; F. equiseti and F. avenaceum were also detected but at low levels. F. poae strains with the nivalenol (NIV) chemotype and F. graminearum strains with 3-acetyl deoxynivalenol (3-ADON) and 15-acetyl deoxynivalenol (15-ADON) chemotypes were commonly detected in the barley grain samples. Nivalenol (597.7, 219.1, and 412.4 µg kg⁻¹) and deoxynivalenol (DON) (264.7, 56.7, and 65.3 µg kg⁻¹) were the two most prevalent mycotoxins contaminating Manitoba barley in 2017, 2018 and 2019, respectively. A substantially higher DON content was detected in grain samples from barley fields with cereals as a preceding crop compared to canola and flax. Furthermore, F. poae proved less sensitive to four triazole fungicides (metconazole, prothioconazole+tebuconazole, tebuconazole, and prothioconazole) than F. graminearum. Findings from this research will assist barley producers with improved understanding of FHB threat levels and optimizing practices for the best management of FHB in barley.

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.

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.

Global guideline for the diagnosis and management of rare mould infections: an initiative of the European Confederation of Medical Mycology in cooperation with the International Society for Human and Animal Mycology and the American Society for Microbiology

With increasing numbers of patients needing intensive care or who are immunosuppressed, infections caused by moulds other than Aspergillus spp or Mucorales are increasing. Although antifungal prophylaxis has shown effectiveness in preventing many invasive fungal infections, selective pressure has caused an increase of breakthrough infections caused by Fusarium, Lomentospora, and Scedosporium species, as well as by dematiaceous moulds, Rasamsonia, Schizophyllum, Scopulariopsis, Paecilomyces, Penicillium, Talaromyces and Purpureocillium species. Guidance on the complex multidisciplinary management of infections caused by these pathogens has the potential to improve prognosis. Management routes depend on the availability of diagnostic and therapeutic options. The present recommendations are part of the One World-One Guideline initiative to incorporate regional differences in the epidemiology and management of rare mould infections. Experts from 24 countries contributed their knowledge and analysed published evidence on the diagnosis and treatment of rare mould infections. This consensus document intends to provide practical guidance in clinical decision making by engaging physicians and scientists involved in various aspects of clinical management. Moreover, we identify areas of uncertainty and constraints in optimising this management.

Invasive infections with Purpureocillium lilacinum: clinical characteristics and outcome of 101 cases from FungiScope® and the literature

OBJECTIVES

To provide a basis for clinical management decisions in Purpureocillium lilacinum infection.

METHODS

Unpublished cases of invasive P. lilacinum infection from the FungiScope® registry and all cases reported in the literature were analysed.

RESULTS

We identified 101 cases with invasive P. lilacinum infection. Main predisposing factors were haematological and oncological diseases in 31 cases (30.7%), steroid treatment in 27 cases (26.7%), solid organ transplant in 26 cases (25.7%), and diabetes mellitus in 19 cases (18.8%). The most prevalent infection sites were skin (n = 37/101, 36.6%) and lungs (n = 26/101, 25.7%). Dissemination occurred in 22 cases (21.8%). Pain and fever were the most frequent symptoms (n = 40/101, 39.6% and n = 34/101, 33.7%, respectively). Diagnosis was established by culture in 98 cases (97.0%). P. lilacinum caused breakthrough infection in 10 patients (9.9%). Clinical isolates were frequently resistant to amphotericin B, whereas posaconazole and voriconazole showed good in vitro activity. Susceptibility to echinocandins varied considerably. Systemic antifungal treatment was administered in 90 patients (89.1%). Frequently employed antifungals were voriconazole in 51 (56.7%) and itraconazole in 26 patients (28.9%). Amphotericin B treatment was significantly associated with high mortality rates (n = 13/33, 39.4%, P = <0.001). Overall mortality was 21.8% (n = 22/101) and death was attributed to P. lilacinum infection in 45.5% (n = 10/22).

CONCLUSIONS

P. lilacinum mainly presents as soft-tissue, pulmonary or disseminated infection in immunocompromised patients. Owing to intrinsic resistance, accurate species identification and susceptibility testing are vital. Outcome is better in patients treated with triazoles compared with amphotericin B formulations.

An Overview of the Management of the Most Important Invasive Fungal Infections in Patients with Blood Malignancies

In patients with hematologic malignancies due to immune system disorders, especially persistent febrile neutropenia, invasive fungal infections (IFI) occur with high mortality. Aspergillosis, candidiasis, fusariosis, mucormycosis, cryptococcosis and trichosporonosis are the most important infections reported in patients with hematologic malignancies that undergo hematopoietic stem cell transplantation. These infections are caused by opportunistic fungal pathogens that do not cause severe issues in healthy individuals, but in patients with hematologic malignancies lead to disseminated infection with different clinical manifestations. Prophylaxis and creating a safe environment with proper filters and air pressure for patients to avoid contact with the pathogens in the surrounding environment can prevent IFI. Furthermore, due to the absence of specific symptoms in IFI, rapid and accurate diagnosis reduces the mortality rate of these infections and using molecular techniques along with standard mycological methods will improve the diagnosis of disseminated fungal infection in patients with hematologic disorders. Amphotericin B products, extended-spectrum azoles, and echinocandins are the essential drugs to control invasive fungal infections in patients with hematologic malignancies, and according to various conditions of patients, different results of treatment with these drugs have been reported in different studies. On the other hand, drug resistance in recent years has led to therapeutic failures and deaths in patients with blood malignancies, which indicates the need for antifungal susceptibility tests to use appropriate therapies. Life-threatening fungal infections have become more prevalent in patients with hematologic malignancies in recent years due to the emergence of new risk factors, new species, and increased drug resistance. Therefore, in this review, we discuss the different dimensions of the most critical invasive fungal infections in patients with hematologic malignancies and present a list of these infections with different clinical manifestations, treatment, and outcomes.

Common traps/pitfalls and emergency diagnosis in dermatopathology

Although all diagnoses in dermatopathology are important, three main groups may be highlighted. One group includes diagnoses that need to be communicated to the treating physician as soon as possible (this review includes infectious process while erythema multiforme and related diseases are discussed elsewhere in this series). A second group has diagnoses significant for their association with syndromes or internal malignancies. And a third group includes malignant lesions that can be confused histologically with benign ones or lesions that have an aggressive behavior unexpected for their apparently low-grade histology. This manuscript describes some of these important diseases and the method we use to reach the diagnosis, and as such it may be considered to be a "survival" guide for the dermatopathologist.

Demonstration of Adventitious Sporulation in Fusarium Petroliphilum Onychomycosis

Fusarium petroliphilum is a recently described species within the Fusarium solani species complex. Some strains of Fusarium species are capable of forming yeast-like structures in tissue as well as in culture through a process known as "adventitious sporulation." Here, we describe the formation of these yeast-like reproductive structures in infected nail tissue obtained from a case of onychomycosis. These structures were also observed in culture grown on RPMI 1640 agar supplemented with 2% glucose. The isolate was resistant to azoles and echinocandins. To the best of our knowledge, this is the first report describing adventitious sporulation in F. petroliphilum and its etiologic role in onychomycosis.

An unusual case of hyalohyphomycosis due to Purpureocillium lilacinum in a patient with myasthenia gravis

Background and Purpose:

Purpureocillium lilacinum (previously known as Paecilomyces lilacinus) and Paecilomyces variotii cause hyalohyphomycosis.

Case report:

In this study, we present a case of multiple subcutaneous abscesses of the lower limbs due to Purpureocillium lilacinum in a patient with myasthenia gravis and uncontrolled diabetes. Subcutaneous involvement of the lower limbs with this fungus is an unusual presentation. Pus aspirate collected on multiple occasions revealed hyaline septate hyphae under microscopic examination and Purpureocillium lilacinum grew on Sabouraud Dextrose Agar. The patient was initially treated by surgical excision and itraconazole therapy. Swelling regressed but discharge was noticed from the excision site after three months of itraconazole therapy. Culture from the discharge material yielded the same fungal growth. Treatment was changed to ketoconazole and he responded.

Conclusion:

This case report emphasizes the importance of identifying Purpureocillium lilacinum at an unusual site like the lower limbs in an immunocompromised patient. Ketoconazole may be used as an alternative treatment option for hyalohyphomycosis caused by Purpureocillium lilacinum.

Angioinvasive fungal infections impacting the skin: Diagnosis, management, and complications

As discussed in the first article in this continuing medical education series, angioinvasive fungal infections pose a significant risk to immunocompromised and immunocompetent patients alike, with a potential for severe morbidity and high mortality. The first article in this series focused on the epidemiology and clinical presentation of these infections; this article discusses the diagnosis, management, and potential complications of these infections. The mainstay diagnostic tests (positive tissue culture with histologic confirmation) are often supplemented with serum biomarker assays and molecular testing (eg, quantitative polymerase chain reaction analysis and matrix-assisted laser desorption ionization time-of-flight mass spectrometry) to ensure proper speciation. When an angioinvasive fungal infection is suspected or diagnosed, further workup for visceral involvement also is essential and may partially depend on the organism. Different fungal organisms have varied susceptibilities to antifungal agents, and knowledge on optimal treatment regimens is important to avoid the potential complications associated with undertreated or untreated fungal infections.

In Vivo Confocal Microscopy Cellular Features of Host and Organism in Bacterial, Fungal, and Acanthamoeba Keratitis

PURPOSE

To determine cellular features of fungal (FK), Acanthamoeba (AK), and bacterial keratitis (BK) using HRT3 in vivo confocal microscopy (IVCM).

DESIGN

Prospective observational cross-sectional study.

METHODS

Eligible participants were adults with microbiologically positive FK, AK, or BK, of size ≥ 3 mm, attending Aravind Eye Hospital from February 2012 to February 2013. Exclusion criteria were descemetocele or perforation. At presentation, IVCM imaging was performed, then corneal scrapes were obtained for culture/light microscopy. An experienced grader (masked to microbiology/clinical features) assessed IVCM images for presence/absence of normal keratocyte-like morphology, stellate interconnected cells with/without visible nuclei, dendritiform cells (DFCs), inflammatory cells in a honeycomb distribution, and organism features. Statistical significance was assessed by logistic regression, adjusted for age, sex, ulcer size, and symptom duration. Main outcome measures were presence/absence of IVCM features in FK, AK, BK.

RESULTS

A total of 183 participants had FK, 18 AK, 17 BK. Acanthamoeba appeared as bright spots (16/18, 89%), double-walled cysts (15/18, 83%), or signet rings (3/18, 17%), and often formed clusters after topical steroid use (univariable odds ratio [OR] 9.98, 95% confidence interval [CI] 1.02-97.96, P = .048). BK was associated with bullae in anterior stroma (OR 9.99, 95% CI: 3.11-32.06, P < .001). Honeycomb distribution of anterior stromal inflammatory cells was associated with FK (univariable OR 2.74, 95% CI: 1.01-7.40, P = .047). Aspergillus ulcers were associated with stromal DFCs (OR 11.05, 95% CI: 1.49-82.13, P = .019) and Fusarium ulcers with stellate appearance of interconnected cell processes with nuclei (OR 0.24, 95% CI: 0.09-0.65, P = .005).

CONCLUSION

Specific cellular and structural features observed using IVCM in microbial keratitis may be associated with organism.

Lung Infections

A review of pulmonary infections of all types with diagnostic and morphological features.

Fatal Purpureocillium lilacinum pneumonia in a green tree python

A 10-y-old female green tree python ( Morelia viridis) died of fungal pneumonia caused by Purpureocillium lilacinum, which was confirmed histologically and by PCR and subsequent DNA sequencing. The same fungal species was cultivated from a swab taken from the terrarium in which the snake was housed. Clinical and environmental P. lilacinum isolates were indistinguishable by the typing method applied, strongly suggesting clonal relatedness of both isolates. Because no other underlying predisposing respiratory infection could be detected by virus-specific PCR or histopathology, P. lilacinum was considered a primary pulmonary pathogen in this tree python.

Fungi that Infect Humans

Fungi must meet four criteria to infect humans: growth at human body temperatures, circumvention or penetration of surface barriers, lysis and absorption of tissue, and resistance to immune defenses, including elevated body temperatures. Morphogenesis between small round, detachable cells and long, connected cells is the mechanism by which fungi solve problems of locomotion around or through host barriers. Secretion of lytic enzymes, and uptake systems for the released nutrients, are necessary if a fungus is to nutritionally utilize human tissue. Last, the potent human immune system evolved in the interaction with potential fungal pathogens, so few fungi meet all four conditions for a healthy human host. Paradoxically, the advances of modern medicine have made millions of people newly susceptible to fungal infections by disrupting immune defenses. This article explores how different members of four fungal phyla use different strategies to fulfill the four criteria to infect humans: the Entomophthorales, the Mucorales, the Ascomycota, and the Basidiomycota. Unique traits confer human pathogenic potential on various important members of these phyla: pathogenic Onygenales comprising thermal dimorphs such as Histoplasma and Coccidioides; the Cryptococcus spp. that infect immunocompromised as well as healthy humans; and important pathogens of immunocompromised patients-Candida, Pneumocystis, and Aspergillus spp. Also discussed are agents of neglected tropical diseases important in global health such as mycetoma and paracoccidiomycosis and common pathogens rarely implicated in serious illness such as dermatophytes. Commensalism is considered, as well as parasitism, in shaping genomes and physiological systems of hosts and fungi during evolution.

Experimental Hyalohyphomycosis by Purpureocillium lilacinum: Outcome of the Infection in C57BL/6 Murine Models

Purpureocillium lilacinum is a filamentous, hyaline fungus considered an emerging pathogen in humans. The aim of our study was to evaluate the outcome of hyalohyphomycosis in C57BL/6 murine models inoculated with two clinical P. lilacinum isolates (S1 and S2). Each isolate was inoculated in mice randomly distributed in immunocompetent (CPT) and immunosuppressed (SPS) groups. Mice were evaluated at day 7, 21, and 45 after inoculation for histopathological analysis, recovery of fungal cells, and immunological studies. Histological analysis showed scarce conidia-like structures in lung tissue from CPT mice and a lot of fungal cells in SPS mice inoculated with S2 compared to mice inoculated with S1. The maximum recovery of fungal cells was seen in CPT mice inoculated with both isolates at day 7, but with mean significantly higher in those inoculated with S2 isolate. Phenotypical characterization of T cells showed TCD8⁺ lymphocytes predominance over TCD4⁺ in immunosuppressed mice infected and control groups. We also observed higher percentages of the central and effector memory/effector phenotype in CPT mice infected with S2 strain, especially in TCD8⁺ in the initial period of infection. Regulatory T cells showed higher percentages in immunosuppressed, predominantly after the acute phase. Our results showed that the P. lilacinum is a fungus capable to cause damages in competent and immunosuppressed experimental hosts. Furthermore, S2 isolate seems to cause more damage to the experimental host and it was possible to identify different cellular subsets involved in the mice immune response.

Emergence of the Molds Other than Aspergillus in Immunocompromised Patients

Immunocompromised patients are at high risk for invasive fungal infections (IFIs); although Aspergillus remains the most common IFI caused by molds, other fungi, such as Mucorales, dematiaceous molds, and Fusarium spp, are being seen with increasing frequency. Presentations can vary, but sinopulmonary and disseminated infections are common. Our understanding of the pathogenesis of these infections is rudimentary. Fungal cultures and histopathology remain the backbone of diagnostics, as no good serologic markers are available. Polymerase chain reaction tests are being developed but currently remain investigational. Management of these infections is usually multidisciplinary, requiring surgical debridement along with antifungal therapy.

Purpureocillium lilacinum keratitis: a case series and review of the literature

OBJECTIVE

To describe the clinical features and risk factors of and optimal antifungal therapy for Purpureocillium lilacinum keratitis.

DESIGN

Retrospective case series in a quaternary referral hospital setting.

METHODS

Comprehensive chart review of patients diagnosed with P. lilacinum keratitis in the past 10 years.

PARTICIPANTS

Four patients were identified. All were aged 60 years or greater, with none having prior ocular trauma. Two had significant potential environmental exposure risks, and 3 were using systemic immunosuppressants for scleritis.

RESULTS

All cases received empirical treatment that included topical corticosteroids. Three were treated with combined oral, topical, and intracameral voriconazole, but developed endophthalmitis necessitating surgery with poor outcomes, including enucleation in 2. One case received combined oral and topical voriconazole with terbinafine, and maintained visual acuity without the need for surgery. All P. lilacinum isolates were susceptible to voriconazole.

CONCLUSIONS

P. lilacinum keratitis is rare, with the major risk factor being immunosuppression. There may be no history of ocular trauma. Microbiological diagnosis and antifungal susceptibility testing is essential. Combination synergistic antifungal therapy with topical voriconazole and oral terbinafine, with addition of systemic voriconazole if needed, results in the best outcome.

Molecular and pathological characterization of Fusarium solani species complex infection in the head and lateral line system of Sphyrna lewini

A severe fungal infection affecting the head and lateral line system was diagnosed in 7 captive scalloped hammerhead sharks Sphyrna lewini in an aquarium in Thailand. Extensive and severe necrotizing cellulitis was consistently observed microscopically along the cephalic and lateral line canals in conjunction with positive fungal cultures for Fusarium sp. Molecular phylogenetic analysis was performed from 3 isolates based on the nucleotide sequences containing internally transcribed spacer (ITS) and a portion of 5.8S and 28S rDNA. The fungus was highly homologous (100%) and closely related to F. solani species complex 2 (FSSC 2), which belongs to Clade 3 of the FSSC. Our results illustrate the histopathological findings and expand upon our knowledge of the prevalence of invasive fusariosis in the head and lateral line system of hammerhead sharks.

A Case of Fungus Ball-Type Pansinusitis Due to Fusarium proliferatum

Incidence of fungal sinusitis due to the genus Fusarium has increased during the last two decades. We report a case of fungus ball sinusitis with multiple sinuses involvement in an Iranian 21-year-old woman. The patient was diagnosed as having a fungus ball-type sinusitis in computed tomography scan. The sinus biopsy revealed fungal structures on histopathological and direct microscopic examinations and a Fusarium species arose in culture. Partial sequencing of the translation elongation factor 1-alpha identified the isolate as F. proliferatum. Removal of all lesions by endoscopic surgery resulted in a favorable outcome. To the best of our knowledge, this is the first case of F. proliferatum-associated fungus ball which involved multi-sinus and highlights the efficiency of molecular methods for discrimination of fungal agents involved.

Role of granulocyte transfusions in invasive fusariosis: systematic review and single-center experience

BACKGROUND

Invasive Fusarium infection is relatively refractory to available antifungal agents. Invasive fusariosis (IF) occurs almost exclusively in the setting of profound neutropenia and/or systemic corticosteroid use. Treatment guidelines for IF are not well established, including the role of granulocyte transfusions (GTs) to counter neutropenia.

STUDY DESIGN AND METHODS

We conducted a systematic review, identifying IF cases where GTs were used as adjunctive therapy to antifungal agents and also report a single-center case series detailing our experience (1996-2012) of all IF cases treated with antifungal agents and GTs. In the systematic review cases, GTs were predominantly collected from nonstimulated donors whereas, in the case series, they were universally derived from dexamethasone- and granulocyte-colony-stimulating factor-stimulated donors.

RESULTS

Twenty-three patients met inclusion criteria for the systematic review and 11 for the case series. Response rates after GTs were 30 and 91% in the review and case series, respectively. Survival to hospital discharge remained low at 30 and 45%, respectively. Ten patients in the systematic review and three in the case series failed to achieve hematopoietic recovery and none of these survived. In the case series, donor-stimulated GTs generated mean "same-day" neutrophil increments of 3.35 × 10(9)  ± 1.24 × 10(9) /L and mean overall posttransfusion neutrophil increments of 2.46 × 10(9)  ± 0.85 × 10(9) /L. Progressive decrements in neutrophil response to GTs in two cases were attributed to GT-related HLA alloimmunization.

CONCLUSION

In patients with IF, donor-stimulated GTs may contribute to high response rates by effectively bridging periods of neutropenia or marrow suppression. However, their utility in the absence of neutrophil recovery remains questionable.

Disseminated fusariosis and hematologic malignancies, a still devastating association. Report of three new cases

BACKGROUND

Fungi of the genus Fusarium are primarily plant pathogens and saprobes that produce disseminated infections in immunologically deficient humans. After aspergillosis, disseminated fusariosis is the second most common cause of invasive infection by filamentous fungi in patients with hematologic malignancies or those undergoing transplants of hematopoietic progenitors.

AIMS

Disseminated fusariosis (DF) is considered an extremely rare infection and has reached a stable incidence rate, but its high mortality rate and the lack of an optimal management protocol have raised increasing interest in this mycosis.

METHODS

We present three cases of DF produced by Fusarium oxysporum species complex, Fusarium solani species complex and the highly unusual Fusarium dimerum in patients with advanced hematological malignancies diagnosed in our hospital between 2007 and 2011. The species level identification of the Fusarium isolates was established by sequencing their TEF1 gene.

RESULTS

The isolates showed low susceptibility to most of the antifungal agents analyzed, except that observed for F. dimerum to amphotericin B (AmB) and terbinafine, and F. oxysporum species complex to AmB. Interestingly, the strain of F. solani species complex exhibited high MIC values for AmB and voriconazole, notwithstanding these drugs were used for treatment with good results. Other relevant aspects to be considered in the treatment of DF are surgically cleaning foci of infection, withdrawing presumably contaminated catheters and recovery from neutropenia.

CONCLUSIONS

The prevention of infection in colonized patients, the maintenance of a high level of diagnostic suspicion for early diagnosis, and the combined, vigorous and prolonged use of L-AmB and voriconazole are essential to decrease the mortality rate of this devastating infection.

Fusarium solani infection in a kidney transplant recipient

Hyalo hypho mycosis due to Fusarium species mainly occurs in immunocompromised hosts. The clinical presentation varies from localized to disseminated involvement. A case of localized cutaneous fusariosis caused by Fusarium solani in a renal transplant patient is described and the skin manifestations of the disease are discussed.

Uncommon opportunistic fungal infections of oral cavity: A review

The majority of opportunistic oral mucosal fungal infections are due to Candida albicans and Aspergillus fumigatus species. Mucor and Cryptococcus also have a major role in causing oral infections, whereas Geotrichum, Fusarium, Rhodotorula, Saccharomyces and Penicillium marneffei are uncommon pathogens in the oral cavity. The broad spectrum of clinical presentation includes pseudo-membranes, abscesses, ulcers, pustules and extensive tissue necrosis involving bone. This review discusses various uncommon opportunistic fungal infections affecting the oral cavity including their morphology, clinical features and diagnostic methods.

Fatal Fusarium solani infection after stem cell transplant for aplastic anemia

Fusarium is a saprophytic and opportunistic pathogen that can cause local tissue infection and life-threatening systemic infection. Systemic infection is rare and is observed primarily in immunocompromised patients. The early diagnosis is difficult, and the optimal treatment is unclear. However, the mortality is high. A 21-year-old man with aplastic anemia was treated with an allogeneic stem cell transplant. He developed fatal Fusarium solani infection. Fusarium species may be overlooked pathogenic fungi in immunocompromised patients, especially bone marrow transplant recipients.

ScedosporiumSpecies Infections and Treatments

Scedosporium species are now increasingly isolated from immunocompromised and immunocompetent patients. Unfortunately, Scedosporium species infections are generally resistant to amphotericin B, and S. prolificans strains are particularly resistant to presently-available antifungal agents. Here we review the microbiology, expanding epidemiology, numerous clinical presentations, and diagnostic tools available for Scedosporium species infections. Finally, we detail the available in vitro, animal model, and clinical data on the treatment of Scedosporium species infections with special emphasis on the role of newer antifungal therapies for these recalcitrant infections.

Microscopic evaluation, molecular identification, antifungal susceptibility, and clinical outcomes in fusarium, Aspergillus and, dematiaceous keratitis

Purpose. Fusarium, Aspergillus, and Dematiaceous are the most common fungal species causing keratitis in tropical countries. Herein we report a prospective study on fungal keratitis caused by these three fungal species. Methodology. A prospective investigation was undertaken to evaluate eyes with presumed fungal keratitis. All the fungal isolates (n = 73) obtained from keratitis infections were identified using morphological and microscopic characters. Molecular identification using sequencing of the ITS region and antifungal susceptibility tests using microdilution method were done. The final clinical outcome was evaluated in terms of the time taken for resolution of keratitis and the final visual outcome. The results were analyzed after segregating the cases into three groups, namely, Fusarium, Aspergillus, and Dematiaceous keratitis. Results. Diagnosis of fungal keratitis was established in 73 (35.9%) cases out of 208 cases. The spectra of fungi isolated were Fusarium spp. (26.6%), Aspergillus spp. (21.6%), and Dematiaceous fungi (11.6%). The sequence of the ITS region could identify the Fusarium and Aspergillus species at the species complex level, and the Dematiaceous isolates were accurately identified. Using antifungal agents such as fluconazole, natamycin, amphotericin B, and itraconazole, the minimum inhibitory concentrations (MICs) for Fusarium spp. were >32 μg/mL, 4–8 μg/mL, 0.5–1 μg/mL, and >32 μg/mL, respectively. Antifungal susceptibility data showed that Curvularia spp. was highly resistant to all the antifungal agents. Overall, natamycin and amphotericin B were found to be the most effective antifungal agents. The comparative clinical outcomes in all cases showed that the healing response in terms of visual acuity of the Dematiaceous group was significantly good when compared with the Fusarium and Aspergillus groups (P < 0.05). The time required for healing in the Fusarium group was statistically significantly less when compared with the Aspergillus and Dematiaceous groups. Conclusion. This study demonstrates important differences in microscopic features of scraping material and antifungal susceptibility between the three groups. Early and accurate identification coupled with the MIC data, and thereby appropriate treatment is crucial for complete recovery.

Paecilomyces variotii as an Emergent Pathogenic Agent of Pneumonia

Paecilomyces variotii is a commonly occurring species in air and food, and it is also associated with many types of human infections. Pneumonia due to Paecilomyces variotii has been rarely reported in the medical literature. The authors report a 48-year-old patient with refractory lymphoma who underwent allogenic hematopoietic cell transplantation and developed pneumonia due to Paecilomyces variotii. They also review the published case reports of pneumonia caused by this fungus.

Fungal diagnosis: how do we do it and can we do better?

BACKGROUND

Morbidity and mortality remain high for patients with invasive fungal infections (IFIs) despite an increasing number of antifungals and other treatments. Many studies indicate that delayed or inaccurate diagnosis and treatment are major causes of poor outcomes in patients with IFIs.

OBJECTIVE

The aim of the current paper is to provide a review of traditional and newer approaches to the diagnosis of IFIs, with a particular focus on invasive candidiasis (IC) and aspergillosis (IA). Recent studies from the author's institution are highlighted, along with an advancement in cryptococcal meningitis diagnosis that should improve the care of AIDS and its opportunistic infection in many developing countries.

FINDINGS

Currently available tools for the diagnosis of IFIs include traditional methods like histopathology, culture, and radiology, and newer antigen- and PCR-based diagnostic assays. Attempts have also been made to predict IFIs based on colonization or other factors, including genetic polymorphisms impacting IFI susceptibility in high-risk patients. Biopsy with histopathologic analysis is often not possible in patients suspected of pulmonary aspergillosis due to increased bleeding risk, and blood cultures for IC, IA, or other IFIs are hindered by poor sensitivity and slow turnaround time which delays diagnosis. Radiology is often used to predict IFI but suffers from inability to differentiate certain pathogens and does not generally provide certainty of IFI diagnosis. Newer antigen-based diagnostics for early diagnosis include the β-glucan assay for IFIs, galactomannan assay for IA, and a recent variation on the traditional cryptococcal antigen (CRAG) test with a Lateral Flow Assay for invasive cryptococcosis. PCR-based diagnostics represent additional tools with high sensitivity for the rapid diagnosis of IFIs, although better standardization of these methods is still required for their routine clinical use.

CONCLUSION

Better understanding of the strengths and weaknesses of currently available diagnostic tools, and further devising linked strategies to best implement them either alone or in combination, would greatly improve early and accurate diagnosis of IFIs and improve their successful management.

A Rare Case of Nasal Septal Perforation Due to Purpureocillium lilacinum: Case Report and Review

Perforations of nasal septum are fairly frequent with an incidence of about 0.9 % and may lead to morbidity than mortality. Common causes are trauma (iatrogenic occasionally nose picking), malignancy, inflammations and infections such as tuberculosis, syphilis, Wegener's granulomatosis, sarcoidosis and fungal infections. Paranasal fungal sinusitis is frequently encountered in clinical practice in both immunocompromised and immunocompetent individuals. Nasal septal perforations caused by species of Aspergillus and Fusarium have been documented. We report a case of nasal septal perforation in a 35-years-old immunocompetent male patient due to Purpureocillium lilacinum, a soil and environmental fungus and an emerging pathogen, which is known to cause various infections in humans with normal and deficient immune system. Fungal aetiology was diagnosed by histopathology and direct smear examination and confirmed by culture. Patient was treated with voriconozole, following Antifungal susceptibility testing (AFST), to which the patient is responding.

Pseudo-outbreak of Lecanicillium and Acremonium species in orthopedic surgery patients

Acremonium species cause a variety of human infections, while Lecanicillium species have not been reported as human pathogens. We describe a pseudo-outbreak involving both organisms, highlighting the role and limitations of molecular methods in the characterization of rare fungal isolates. Repeated isolation of these fungi from patient tissue samples raises concerns about exogenous contamination in the hospital environment.

Fusarium verticillioides fungemia in a liver transplantation patient: successful treatment with voriconazole

Fusarium is an opportunistic fungal pathogen which is emerging as a significant cause of morbidity and mortality in immunocompromised hosts. We present a rare case of F. verticillioides fungemia that occurred in a patient who underwent a second orthotopic liver transplantation for chronic rejection and completely responded to treatment with voriconazole.

Purpureocillium lilacinum as a cause of cavitary pulmonary disease: a new clinical presentation and observations on atypical morphologic characteristics of the isolate

The first case of cavitary pulmonary disease caused by Purpureocillium lilacinum is described. The isolate showed atypical microscopic characteristics similar to Acremonium and Fusarium spp., which necessitated molecular identification by sequencing of multiple conserved loci. The patient responded to voriconazole, reinforcing its therapeutic efficacy for P. lilacinum infections.

A Rare Case of Fungal Maxillary Sinusitis due to Paecilomyces lilacinus in an Immunocompetent Host, Presenting as a Subcutaneous Swelling

Paecilomyces is a colonizing fungal species which usually causes keratitis, endocarditis, sinusitis, nephritis, fungemia, cutaneous, and subcutaneous infections in immunocompromised host. Very rarely, it causes similar infection in immunocompetent host without any risk factors. We report a case of maxillary sinusitis due to Paecilomyces lilacinus in a 65–year-old immunocompetent male, who presented with a subcutaneous swelling below the left eye. The lesion was excised by surgery and treated with itraconazole for 6 months based on culture and sensitivity. After 1 year of follow up, he is free of symptoms with no evidence of recurrence.

Synchronous infection with Mycobacterium chelonae and Paecilomyces in a heart transplant patient

A 41-year-old male who was 3 years status post heart transplant presented with a 3-month history of painful erythematous nodules and ulcers on his lower legs and right hand. First, Mycobacterium chelonae infection was revealed through several biopsies with molecular sequence analysis, and combination treatment, including clarithromycin, was started. During the treatment, lesions of the legs showed an improvement, but a fluctuant erythematous nodule on the thumb did not respond. Repetitive biopsy from the thumb ultimately identified Paecilomyces species and the patient was treated with itraconazole and terbinafine sequentially. Our case is the first report, to our knowledge, of synchronous infection with non-tuberculous mycobacteria (NTM) and Paecilomyces in a solid organ transplant recipient. Our findings highlight the importance of recognizing cutaneous NTM infections or deep mycoses, as well as the importance of choosing an appropriate treatment.