Fungal Keratitis Caused by Colletotrichum dematium: Case Study and Review

Mycopathologia - Colletotrichum species are known as important pathogens of plants with an impact on crop production. Some of these species are also known as a cause of rare ophthalmic infections...     

Fungal extracellular ribonucleases (Review)

Results of studies of certain fungal extracellular ribonucleases mainly isolated from representatives of the genera Aspergillus and Penicillium are summarized. The isolation of these enzymes in highly purified states in the 1970-1980s strongly stimulated further studies of their structure, functions, and mechanisms of action. This also promoted the use of ribonucleases as catalysts in oligoribonucleotide syntheses and as objects of comparative and evolutionary biochemistry and other research works. Results of studies of the primary, secondary, and spatial structures of guanyl-specific fungal ribonucleases are reviewed. These studies revealed a high homology within the subfamilies of fungal, bacterial, and actinomycete RNases. Characteristics of the nonspecific Pb2 RNase are considered.     

Fungal Extracellular RNases (Review)

Studies of certain fungal extracellular RNases mainly isolated from representatives of the genera Aspergillus and Penicillium are reviewed. The isolation of these enzymes in highly purified states in the 1970s and 1980s strongly stimulated further studies of their structure, functions, and mechanisms of action. This also promoted the use of RNases as catalysts in oligoribonucleotide syntheses and as objects of comparative and evolutionary biochemical and other studies. Results of determinations of the primary, secondary, and spatial structures of guanyl-specific fungal RNases are reviewed. These studies revealed considerable homology within the subfamilies of fungal, bacterial, and actinomycete RNases. Characteristics of the nonspecific RNase Pb₂ are considered.     

Fungal Endocarditis Observed Over an 8-Year Period and a Review of the Literature

Background

Fungal endocarditis (FE) is a “modern” disease that is considered an emerging cause of infective endocarditis (IE). The most frequently identified fungal pathogens are Candida spp., which are responsible for up to two-thirds of all cases; the remaining cases are due to Aspergillus spp., Histoplasma capsulatum or, more rarely, other yeasts and moulds.

Objectives

To describe the prevalence, clinical characteristics and outcome of FE diagnosed in a single tertiary centre and review the literature concerning FE.

Design and setting

An 8-year retrospective review of the case records of patients attending a single Italian University Centre and diagnosed as having definite or probable IE as defined by the modified Duke criteria.

Results

Six patients were identified from 229 episodes of IE: five cases involved a prosthetic valve, and one a native valve of an intravenous drug user. Five cases were caused by Candida spp. (two by C. albicans, one each by C. lusitaniae, C. dubliniensis and C. glabrata) and one by Aspergillus flavus. Three patients were treated by means of surgery plus antifungal therapy; two received antifungal therapy alone. Three patients survived, but only the patient with Aspergillus endocarditis was followed up for a long time.

Conclusions

FE is difficult to diagnose but generally associated with healthcare infections. The optimal treatment is poorly characterised, and international collaborative studies are urgently needed to evaluate newer antifungal agents.     

Fungal Bloodstream Co-infection by Trichosporon asahii in a COVID-19 Critical Patient: Case Report and Literature Review

Mycopathologia - Opportunistic infections are serious complications in critically ill COVID-19 patients, especially co-infections with bacterial and fungal agents. Here we report a rare case of...     

Allergic Fungal Sinusitis Caused by Exserohilum rostratum and Literature Review

Mycopathologia - A case of allergic fungal sinusitis (AFS) caused by Exserohilum rostratum, proven by culture and histopathology of the biopsy material, is described. The identity of the isolate...     

Rare Fungal Infections in Children: An Updated Review of the Literature

An increasing trend of reports of rare fungal diseases has been observed to be mainly associated with the substantial increase of high-risk immunocompromised children, as well as with the selective pressure of antifungal drugs. On the other hand, recent reports have shown that several species of these rare fungi may also cause infections in immunocompetent children without obvious underlying conditions. The clinical spectrum of these infections, and most importantly their outcome, varies greatly, implying for a rather heterogenic group of pediatric infections. Various types of superficial and subcutaneous fungal infections, as well as systemic and disseminated life-threatening infections, have been reported. Prompt diagnosis and appropriate treatment of rare fungal diseases in children remains a great challenge. Several treatment options have been used, ranging from localized to combination treatment with extensive surgical excision and long-term antifungal therapy. We review contemporary data of rare fungal infections in pediatric patients focusing on epidemiology, mycology, management and outcome, published during the last three years.     

Invasive Fungal Infection Caused by Exophiala dermatitidis in a Patient After Lung Transplantation: Case Report and Literature Review

Mycopathologia - This report describes a case of invasive Exophiala dermatitidis infection after double lung transplantation in a 76-year-old man. After thoracotomy, the patient’s wound...     

Fungal molecular diagnostics: a mini review

Conventional methods to identify fungi have often relied on identification of disease symptoms, isolation and culturing of environmental organisms, and laboratory identification by morphology and biochemical tests. Although these methods are still fundamental there is an increasing move towards molecular diagnostics of fungi in all fields. In this review, some of the molecular approaches to fungal diagnostics based on polymerase chain reaction (PCR) and DNA/RNA probe technology are discussed. This includes several technological advances in PCR-based methods for the detection, identification and quantification of fungi including real-time PCR which has been successfully used to provide rapid, quantitative data on fungal species from environmental samples. PCR and probe based methods have provided new tools for the enumeration of fungal species, but it is still necessary to combine the new technology with more conventional methods to gain a fuller understanding of interactions occurring in the environment. Since its introduction in the mid 1980's PCR has provided many molecular diagnostic tools, some of which are discussed within this review, and with the advances in micro-array technology and real-time PCR methods the future is bright for the development of accurate, quantitative diagnostic tools that can provide information not only on individual fungal species but also on whole communities.     

Fungal decolorization of dye wastewaters: a review

In recent years, there has been an intensive research on fungal decolorization of dye wastewater. It is becoming a promising alternative to replace or supplement present treatment processes. This paper examines various fungi, living or dead cells, which are capable of decolorizing dye wastewaters; discusses various mechanisms involved; reports some elution and regeneration methods for fungal biomass; summarizes the present pretreatment methods for increasing the biosorption capacity of fungal biomass; discusses the effect of various factors on decolorization.     

Fungal respiration: a fusion of standard and alternative components

In animals, electron transfer from NADH to molecular oxygen proceeds via large respiratory complexes in a linear respiratory chain. In contrast, most fungi utilise branched respiratory chains. These consist of alternative NADH dehydrogenases, which catalyse rotenone insensitive oxidation of matrix NADH or enable cytoplasmic NADH to be used directly. Many also contain an alternative oxidase that probably accepts electrons directly from ubiquinol. A few fungi lack Complex I. Although the alternative components are non-energy conserving, their organisation within the fungal electron transfer chain ensures that the transfer of electrons from NADH to molecular oxygen is generally coupled to proton translocation through at least one site. The alternative oxidase enables respiration to continue in the presence of inhibitors for ubiquinol:cytochrome c oxidoreductase and cytochrome c oxidase. This may be particularly important for fungal pathogens, since host defence mechanisms often involve nitric oxide, which, whilst being a potent inhibitor of cytochrome c oxidase, has no inhibitory effect on alternative oxidase. Alternative NADH dehydrogenases may avoid the active oxygen production associated with Complex I. The expression and activity regulation of alternative components responds to factors ranging from oxidative stress to the stage of fungal development.     

Fungal symbioses in hornworts: a chequered history

Hornworts are considered the sister group to vascular plants, but their fungal associations remain largely unexplored. The ancestral symbiotic condition for all plants is, nonetheless, widely assumed to be arbuscular mycorrhizal with Glomeromycota fungi. Owing to a recent report of other fungi in some non-vascular plants, here we investigate the fungi associated with diverse hornworts worldwide, using electron microscopy and molecular phylogenetics. We found that both Glomeromycota and Mucoromycotina fungi can form symbioses with most hornworts, often simultaneously. This discovery indicates that ancient terrestrial plants relied on a wider and more versatile symbiotic repertoire than previously thought, and it highlights the so far unappreciated ecological and evolutionary role of Mucoromycotina fungi.     

Solitary Candida albicans Infection Causing Fournier Gangrene and Review of Fungal Etiologies

Polymicrobial bacterial infections are commonly found in cases of Fournier gangrene (FG), although fungal growth may occur occasionally. Solitary fungal organisms causing FG have rarely been reported. The authors describe a case of an elderly man with a history of diabetes who presented with a necrotizing scrotal and perineal soft tissue infection. He underwent emergent surgical debridement with findings of diffuse urethral stricture disease and urinary extravasation requiring suprapubic tube placement. Candida albicans was found to be the single causative organism on culture, and the patient recovered well following antifungal treatment. Fungal infections should be considered as rare causes of necrotizing fasciitis and antifungal treatment considered in at-risk immunodeficient individuals.Key words: Fournier gangrene, Fournier’s Gangrene Severity Index, Candida albicansFournier gangrene (FG) is a rare, rapidly progressive, necrotizing infection of the perineum and genital area that was first described in 1883 by Jean Alfred Fournier in five young male patients.¹ The infectious flora causing necrotizing fasciitis are typically polymicrobial, involving aerobic and anaerobic bacteria derived from gastrointestinal, genitourinary, and cutaneous sources.^2,3 Certain predisposing conditions increase the risk of developing FG, including diabetes, chronic kidney disease, immunosuppression, local trauma, urethral stricture, or genitourinary infections.^4–6It is essential to diagnose FG early and treat it emergently because the infection can quickly progress, with mortality rates of 7.5% to 50% cited in various series.^7,8 Aggressive management involves hemodynamic stabilization, broad spectrum antibiotics to empirically cover all potential organisms, and wide surgical debridement.^3–5 Early surgical debridement with excision of all nonviable tissue is the most important component of treatment. Multiple surgical debridements are often required, as the areas of cutaneous involvement may not indicate the full extent of subcutaneous disease.⁵Rapid initiation of broad spectrum antibiotic coverage is also necessary to stabilize the presenting patient with FG before and after surgical management. The infection is generally caused by three or more microorganisms, most commonly Escherichia coli, Proteus, Enterococcus, and anaerobes.⁴ Fungal etiologies of necrotizing infections are rare but have been increasingly reported in the literature.^9–12 Candida species are commonly part of the normal flora in the gastrointestinal and genitourinary tracts of humans but may cause acute disease in the setting of compromised host immunity. This report describes a case of primary C albicans necrotizing fasciitis of the genitalia and reviews the literature regarding fungal FG to determine possible predisposing factors.     

Fungal horizons: the Asilomar Fungal Genetics Conference 2007

This meeting report covers advances presented at the 2007 Asilomar Fungal Genetics Conference that expand our understanding of fungal biology and the myriad ways in which studies of organisms in this ubiquitous and successful kingdom of life advance an understanding of conserved biological principles.     

Invasive Geotrichum clavatum Fungal Infection in an Acute Myeloid Leukaemia Patient: A Case Report and Review

Invasive Geotrichum clavatum fungal infections are extremely rare and unusual, occurring nearly exclusively in patients experiencing prolonged neutropenia during the treatment for acute myeloid leukaemia. Several groups of cases of fatal G. clavatum infection were reported in France between 2011 and 2012, but the ecological niche has not yet been identified. We report a case of a 32-year-old patient with acute myeloid leukaemia who developed G. clavatum sepsis with primary peritonitis, hepatic nodular lesions, and multivisceral failure during aplasia after induction followed by salvage chemotherapy. He was treated with voriconazole and is still alive 1 year after with controlled disease. We then discuss the epidemiological, clinical, and therapeutic features of these serious fungal infections compared to the published data.