New spectrum of fungal infections in patients with cancer

Recent developments in less known and multi-resistant fungal opportunists

Fungal infections have increased in recent years due to host factors, such as oncohaematological and transplant-related disorders, immunosuppressive therapy, and AIDS. Additionally, molecular and proteomic facilities have become available to identify previously unrecognizable opportunists. For these reasons, reports on less-known and recalcitrant mycoses, such as those caused by black fungi, hyaline filamentous fungi, coelomycetes, Mucorales, and non-Candida yeasts have emerged. In this review, novel taxonomy in these groups, which often are multi-resistant to one or several classes of antifungals, is discussed. Clinical presentations, diagnosis and current treatment of some major groups are summarised.

Fungal Gut Microbiota Dysbiosis and Its Role in Colorectal, Oral, and Pancreatic Carcinogenesis

The association between bacterial as well as viral gut microbiota imbalance and carcinogenesis has been intensively analysed in many studies; nevertheless, the role of fungal gut microbiota (mycobiota) in colorectal, oral, and pancreatic cancer development is relatively new and undiscovered field due to low abundance of intestinal fungi as well as lack of well-characterized reference genomes. Several specific fungi amounts are increased in colorectal cancer patients; moreover, it was observed that the disease stage is strongly related to the fungal microbiota profile; thus, it may be used as a potential diagnostic biomarker for adenomas. Candida albicans, which is the major microbe contributing to oral cancer development, may promote carcinogenesis via several mechanisms, mainly triggering inflammation. Early detection of pancreatic cancer provides the opportunity to improve survival rate, therefore, there is a need to conduct further studies regarding the role of fungal microbiota as a potential prognostic tool to diagnose this cancer at early stage. Additionally, growing attention towards the characterization of mycobiota may contribute to improve the efficiency of therapeutic methods used to alter the composition and activity of gut microbiota. The administration of Saccharomyces boulardii in oncology, mainly in immunocompromised and/or critically ill patients, is still controversial.

Synthesis, antifungal activity and potential mechanism of fusidic acid derivatives possessing amino-terminal groups

Aim: Fusidic acid (FA) is a narrow-spectrum bacteriostatic antibiotic. We inadvertently discovered that a FA derivative modified by an amino-terminal group at the 3-OH position, namely 2, inhibited the growth of Cryptococcus neoformans. Methods & results: Multiscale molecular modeling approaches were used to analyze the binding modes of 2 with eEF2. FA derivatives modified at the 3-OH position were designed based on in silico models; seven derivatives possessing different amino-terminal groups were synthesized and tested in vitro for antifungal activity against C. neoformans. Conclusion: Compound 7 had the strongest minimum inhibitory concentration. Two protonated nitrogen atoms of 7 interacted with a negative electrostatic pocket of eEF2 likely explain the superiority of 7-2.

Successful Treatment of Catheter Related Blood Stream Infection By Millerozyma farinosa with Micafungin: A Case Report

Millerozyma farinosa (formerly Pichia farinosa) is halotolerant yeast mainly found in food and ubiquitous in the environment. It was a rare yeast pathogen, but it has recently emerged as a cause of fungemia in immunocompromised patients. Optimal therapy for invasive fungal infection by this pathogen remains unclear. We report a case of catheter related blood stream infection caused by M. farinosa in a 71-year-old patient who recovered successfully after removal of the central venous catheter and treatment with micafungin.

Impact of Surgical Treatment on Paranasal Fungal Infections in Bone Marrow Transplant Patients

Invasive fungal sinusitis can develop in immunosuppressed patients. A more complex problem is immunosuppressed patients who have undergone bone marrow transplantation. For a prolonged period, they are both neutropenic and thrombocytopenic. Survival in these patients is poor, and the role for extensive surgical intervention for sinus disease has to be weighed against the risk and the potential that this is a systemic disease. Between January 1983 and June 1993, 29 bone marrow transplant recipients with documented invasive fungal infections of the sinuses and paranasal tissues required surgical intervention. This represents 1.7% of the total 1692 bone marrow transplants performed. There were 22 allogeneic, 6 autologous, and 3 unrelated donor transplants, with two patients receiving two separate grafts. Underlying diseases included 24 hematologic malignancies and 5 other disorders, including 1 aplastic anemia and 1 solid tumor. The mortality rate from the initial fungal infection was 62%. Twenty-seven percent resolved the initial infections but subsequently died of other causes. All patients received medical management, such as amphotericin, rifampin, and colony-stimulating factors, in addition to surgical intervention. Surgical management ranged from minimally invasive procedures to extensive resections including medial maxillectomies. Sixty-one percent of the patients who died of the initial infection had undergone extensive surgical procedures versus 55% of those who resolved the infection. Recovery of neutrophil counts was required to clear the infection but did not necessarily predict a good outcome because 50% of those who died of the infection had experienced neutrophil recovery. White blood cell counts at the time of surgery were not significantly different between the two groups. Prognosis was poor when cranial and orbital involvement and/or bony erosion occurred.

A proteomic and ultrastructural characterization of Aspergillus fumigatus' conidia adaptation at different culture ages

The airborne fungus Aspergillus fumigatus is one of the most common agents of human fungal infections with a remarkable impact on public health. However, A. fumigatus conidia atmospheric resistance and longevity mechanisms are still unknown. Therefore, in this work, the processes underlying conidial adaptation were studied by a time course evaluation of the proteomics and ultrastructural changes of A. fumigatus' conidia at three time-points selected according to relevant changes previously established in conidial survival rates. The proteomics characterization revealed that conidia change from a highly active metabolic to a dormant state, culminating in cell autolysis as revealed by the increased levels of hydrolytic enzymes. Structural characterization corroborates the proteomics data, with noticeable changes observed in mitochondria, nucleus and plasma membrane ultrastructure, accompanied by the formation of autophagic vacuoles. These changes are consistent with both apoptotic and autophagic processes, and indicate that the changes in protein levels may anticipate those in cell morphology.

SIGNIFICANCE

The findings presented in this work not only clarify the processes underlying conidial adaptation to nutrient limiting conditions but can also be exploited for improving infection control strategies and in the development of new therapeutical drugs. Additionally, the present study was deposited in a public database and thus, it may also be a valuable dataset to be used by the scientific community as a tool to understand and identified other potential targets associated with conidia resistance.

Current Understanding of Acute Bovine Liver Disease in Australia

Acute bovine liver disease (ABLD) is a hepatotoxicity principally of cattle which occurs in southern regions of Australia. Severely affected animals undergo rapid clinical progression with mortalities often occurring prior to the recognition of clinical signs. Less severely affected animals develop photosensitization and a proportion can develop liver failure. The characteristic histopathological lesion in acute fatal cases is severe, with acute necrosis of periportal hepatocytes with hemorrhage into the necrotic areas. Currently there are a small number of toxins that are known to cause periportal necrosis in cattle, although none of these have so far been linked to ABLD. Furthermore, ABLD has frequently been associated with the presence of rough dog’s tail grass (Cynosurus echinatus) and Drechslera spp. fungi in the pasture system, but it is currently unknown if these are etiological factors. Much of the knowledge about ABLD is contained within case reports, with very little experimental research investigating the specific cause(s). This review provides an overview of the current and most recently published knowledge of ABLD. It also draws on wider research and unpublished reports to suggest possible fungi and mycotoxins that may give rise to ABLD.

Concentrations and identification of culturable airborne fungi in underground stations of the Seoul metro

The purpose of this study was to measure the culturable airborne fungi (CAF) concentrations in the underground subway stations of Seoul, Korea at two time points. This study measured the CAF concentrations in enclosed environments at 16 underground stations of the Seoul Metro in 2006 and 2013 and investigated the effects of various environmental factors, including the presence of platform screen doors, temperature, relative humidity, and number of passengers. CAF concentrations at the stations in 2006 were significantly higher than that at the same stations in 2013 (p < 0.001). Furthermore, there was a significant correlation between CAF concentration and relative humidity (r = 0.311, p < 0.05). Geotrichum and Penicillium were the predominant genera. The CAF concentrations in stations with an operating supply air were significantly higher than that in stations with no supply air (p < 0.001). Therefore, it is recommended that special attention be given to stations with clean supplied air to improve the indoor air quality of these subway stations.

Host impairments in patients with neoplastic diseases

Healthy individuals possess an immune system comprising physical barriers, innate and acquired immunity as well as the indigenous microflora that populate the body surfaces. The immune system maintains constant vigilance over the body at the cellular level as well as at the interface between the host integument and the resident microflora. However, neoplastic diseases and their treatment often lead to impaired immunity resulting in an increased risk of infections due to viruses, bacteria, fungi, and protozoa. This chapter explores the various aspects of host impairment focusing on the components of immunity and the interplay between them to explain why it is that these patients succumb to infections per se. In so doing, we hope that the reader will be better equipped to understand the risks patients face so as to anticipate potential infectious complications and implement appropriate measures to help attain successful remission of the neoplastic diseases and maintain the best quality of life for the patient.

Insights into the life cycle of yeasts from the CTG clade revealed by the analysis of the Millerozyma (Pichia) farinosa species complex

Among ascomycetous yeasts, the CTG clade is so-called because its constituent species translate CTG as serine instead of leucine. Though the biology of certain pathogenic species such as Candida albicans has been much studied, little is known about the life cycles of non-pathogen species of the CTG clade. Taking advantage of the recently obtained sequence of the biotechnological Millerozyma (Pichiasorbitophila) farinosa strain CBS 7064, we used MLST to better define phylogenic relationships between most of the Millerozyma farinosa strains available in public collections. This led to the constitution of four phylogenetic clades diverging from 8% to 15% at the DNA level and possibly constituting a species complex (M. farinosa) and to the proposal of two new species:Millerozyma miso sp. nov. CBS 2004^T ( = CLIB 1230^T) and Candida pseudofarinosa sp. nov.NCYC 386^T( = CLIB 1231^T).Further analysis showed that M. farinosa isolates exist as haploid and inter-clade hybrids. Despite the sequence divergence between the clades, secondary contacts after reproductive isolation were evidenced, as revealed by both introgression and mitochondria transfer between clades. We also showed that the inter-clade hybrids do sporulate to generate mainly viable vegetative diploid spores that are not the result of meiosis, and very rarely aneuploid spores possibly through the loss of heterozygosity during sporulation. Taken together, these results show that in this part of the CTG clade, non-Mendelian genetic exchanges occur at high rates through hybridization between divergent strainsfrom distinct clades and subsequent massive loss of heterozygosity. This combination of mechanisms could constitute an alternative sexuality leading to an unsuspected biodiversity.

Mucormycosis caused by unusual mucormycetes, non-Rhizopus, -Mucor, and -Lichtheimia species

Rhizopus, Mucor, and Lichtheimia (formerly Absidia) species are the most common members of the order Mucorales that cause mucormycosis, accounting for 70 to 80% of all cases. In contrast, Cunninghamella, Apophysomyces, Saksenaea, Rhizomucor, Cokeromyces, Actinomucor, and Syncephalastrum species individually are responsible for fewer than 1 to 5% of reported cases of mucormycosis. In this review, we provide an overview of the epidemiology, clinical manifestations, diagnosis of, treatment of, and prognosis for unusual Mucormycetes infections (non-Rhizopus, -Mucor, and -Lichtheimia species). The infections caused by these less frequent members of the order Mucorales frequently differ in their epidemiology, geographic distribution, and disease manifestations. Cunninghamella bertholletiae and Rhizomucor pusillus affect primarily immunocompromised hosts, mostly resulting from spore inhalation, causing pulmonary and disseminated infections with high mortality rates. R. pusillus infections are nosocomial or health care related in a large proportion of cases. While Apophysomyces elegans and Saksenaea vasiformis are occasionally responsible for infections in immunocompromised individuals, most cases are encountered in immunocompetent individuals as a result of trauma, leading to soft tissue infections with relatively low mortality rates. Increased knowledge of the epidemiology and clinical presentations of these unusual Mucormycetes infections may improve early diagnosis and treatment.

Epidemiology and outcome of Rhodotorula infection in haematological patients

Rhodotorula spp. are emergent opportunistic pathogens, particularly in haematological patients. However, no systematic review of this infection has been undertaken in this high-risk patient group. The aim of this study was to review all reported cases of Rhodotorula infection to determine the epidemiology and outcome of this infection in this high-risk population. The 29 reported cases were fungaemias. The most common underlying haematological disorder was the presence of acute leukaemia (65.5%). Rhodotorula mucilaginosa was the species found more frequently (79.3%). Most cases (58.6%) had several risk factors (≥ 3) simultaneously. The most common predisposing factors were the presence of central venous catheter (CVC, 100%) and neutropenia (62.1%). A substantial number of patients (81.5%) received antifungal treatment with amphotericin B. The overall mortality was higher (13.8%) than that described in non-haematological patients (5.8% in solid-organ neoplasms and 9% in AIDS or other chronic diseases). Patients with acute leukaemia had a higher mortality rate (15.7%) than patients with non-Hodgkin's lymphoma (0%). Our data suggest that patients with acute leukaemia might be managed as high-risk patients and intensive measures might be taken. In addition, it appears that the subgroup of patients without acute leukaemia have a good outcome and might be managed as low-risk patients with a less intensive approach.

Eukaryotic diversity in an anaerobic aquifer polluted with landfill leachate

Eukaryotes may influence pollutant degradation processes in groundwater ecosystems by activities such as predation on bacteria and recycling of nutrients. Culture-independent community profiling and phylogenetic analysis of 18S rRNA gene fragments, as well as culturing, were employed to obtain insight into the sediment-associated eukaryotic community composition in an anaerobic sandy aquifer polluted with landfill leachate (Banisveld, The Netherlands). The microeukaryotic community at a depth of 1 to 5 m below the surface along a transect downgradient (21 to 68 m) from the landfill and at a clean reference location was diverse. Fungal sequences dominated most clone libraries. The fungal diversity was high, and most sequences were sequences of yeasts of the Basidiomycota. Sequences of green algae (Chlorophyta) were detected in parts of the aquifer close (<30 m) to the landfill. The bacterium-predating nanoflagellate Heteromita globosa (Cercozoa) was retrieved in enrichments, and its sequences dominated the clone library derived from the polluted aquifer at a depth of 5 m at a location 21 m downgradient from the landfill. The number of culturable eukaryotes ranged from 10(2) to 10(3) cells/g sediment. Culture-independent quantification revealed slightly higher numbers. Groundwater mesofauna was not detected. We concluded that the food chain in this polluted aquifer is short and consists of prokaryotes and fungi as decomposers of organic matter and protists as primary consumers of the prokaryotes.

Fungal Infections

The incidence of invasive fungal infections has increased dramatically over the past two decades, mostly due to an increase in the number of immunocompromised patients.1–4 Patients who undergo chemotherapy for a variety of diseases, patients with organ transplants, and patients with the acquired immune deficiency syndrome have contributed most to the increase in fungal infections.5 The actual incidence of invasive fungal infections in transplant patients ranges from 15% to 25% in bone marrow transplant recipients to 5% to 42% in solid organ transplant recipients.6,7 The most frequently encountered are Aspergillus species, followed by Cryptococcus and Candida species. Fungal infections are also associated with a higher mortality than either bacterial or viral infections in these patient populations. This is because of the limited number of available therapies, dose-limiting toxicities of the antifungal drugs, fewer symptoms due to lack of inflammatory response, and the lack of sensitive tests to aid in the diagnosis of invasive fungal infections.1 A study of patients with fungal infections admitted to a university-affiliated hospital indicated that community-acquired infections are becoming a serious problem; 67% of the 140 patients had community-acquired fungal pneumonia.8

Endophthalmitis due to Trichosporon beigelii in acute leukemia

We describe 2 patients with hematologic malignancy who developed endophthalmitis due to Trichosporon beigelii during the course of treatment with multiagent chemotherapy. Blood cultures revealed T beigelii for both patients. Although one of the patients was treated with fluconazole (FLCZ) and 5-fluorocytosine, the trichosporonous endophthalmitis was resistant to both drugs. This patient subsequently received amphotericin B (AMPH-B) therapy, and the eyes were treated with vitrectomy. The second patient also received AMPH-B for FLCZ-resistant trichosporonous chorioretinitis. In both patients, systemic treatment with AMPH-B successfully resolved the trichosporonous endophthalmitis that was resistant to multiple antifungal drugs. Endophthalmitis due to trichosporonosis is difficult to treat. The administration of AMPH-B is likely to be more effective in treating endophthalmitis due to trichosporonosis when the disease is at an early stage.

Suitability of yeast- and Escherichia coli-expressed hepatitis B virus core antigen derivatives for detection of anti-HBc antibodies in human sera

Antibody to hepatitis B virus core antigen (anti-HBc) is one of the most important serological markers during hepatitis B virus (HBV) infection. The quality of the hepatitis B virus core antigen (HBcAg; diagnostic antigen) is crucial to the accuracy of anti-HBc detection. In an attempt to explore the suitability of recombinant HBcAg (rHBcAg) for diagnostic purposes, HBcAg was expressed in Escherichia coli (E. coli) and Pichia pastoris (P. pastoris) and evaluated for the detection of anti-HBc. The expression level of the recombinant protein satisfied the criteria for large-scale biologic production. P. pastoris- and E. coli-derived rHBcAg were purified with gel filtration followed by sucrose gradient (reagents A and C) or with a monoclonal anti-HBc antibody binding (reagents B and D) and were utilized to detect anti-HBc in competitive inhibition enzyme-linked immunosorbent assay (ELISA) format. The ELISA using P. pastoris-derived rHBcAg had a higher specificity and sensitivity than that using E.coli-derived rHBcAg to detect the anti-HBc standard panel. Serum specimens were collected from HBV-infected patients and healthy individuals (voluntary blood donors). Anti-HBc was detected in those specimens using P. pastoris- and E. coli-derived rHBcAg. The positive rate of anti-HBc detection in HBV-infected patients' sera was 100% with reagents A and B, 96.4% with reagent C, and 93.6% with reagent D. The negative rate in healthy control sera was 100% with reagents A and B, 97.0% with reagent C, and 99.7% with reagent D. These data indicate that P. pastoris-derived rHBcAg is superior to E.coli-derived rHBcAg for the detection of anti-HBc using the diagnostic ELISA.

Pichia farinosa bloodstream infection in a lymphoma patient

We describe a case of Pichia farinosa bloodstream infection in a lymphoma patient. Phenotypic methods failed to identify the isolate, which was identified by sequence-based methods. This case highlights the importance of implementing molecular methods for the identification of rare fungal pathogens.

Central venous catheter-associated fungemia due toRhodotorulaspp. – A systematic review

Rhodotorula spp. are emergent opportunistic pathogens, particularly in immunocompromised individuals. They have been associated with endocarditis, peritonitis, meningitis endophthalmitis and catheter-associated fungemia. The aim of this study was to review all cases of central venous catheter-related fungemia due to Rhodotorula spp. reported in the literature in order to determine the best management of this uncommon infection. All patients but one in the 88 cases examined had some form of underlying disease including sixty-nine (78.4%) who had cancer. Rhodotorula mucilaginosa was the species most frequently recovered (75%), followed by Rhodotorula glutinis (6%). Amphotericin B deoxycholate was the most common antifungal agent used as treatment and the overall mortality was 9.1% in this review. This fungemia is a rare disease which can be found in immunocompromised and in the intensive care patients. The use of specific antifungal therapy may be associated with an increase in the survival. It should be noted that Rhodotorula spp. is resistant to fluconazole.

Invasive Fungal Sinusitis Caused by Pseudallescheria Boydii: Case Report and Literature Review

Fungal sinusitis secondary to Pseudallescheria boydii is rare, as only 25 cases have been previously reported in the literature. Although P boydii resembles Aspergillus on pathologic examination, it is typically resistant to amphotericin B. Therefore, culture is necessary to differentiate the two. Patients with P boydii sinusitis should generally be treated with a combination of surgery and antifungal therapy. Combination treatment is particularly important for immunocompromised patients with fungal invasion because mortality among these patients is high. The prognosis is better for immunocompetent patients, even those with fungal invasion. We describe a new case of invasive fungal sinusitis secondary to P boydii infection, and we review the literature on this emerging pathogen.

Epidemiology and Outcome of Rhodotorula Fungemia in a Tertiary Care Hospital

We reviewed demographic data, risk factors, treatment, and outcomes associated with Rhodotorula fungemia in a tertiary care hospital during 2002-2005. Rhodotorula species caused fungemic episodes in 7 patients during the 4-year period that we studied. The most common predisposing factors were patients with hematological and solid malignancy receiving corticosteroids and cytotoxic drugs, the presence of central venous catheters, and the use of broad-spectrum antibiotics. Because of Rhodotorula species's intrinsic resistance to triazole and echinocandin antifungal agents, patients receiving fluconazole and caspofungin might be susceptible to the development of breakthrough Rhodotorula fungemia.

Efficacy of voriconazole in a guinea pig model of invasive trichosporonosis

We have evaluated the efficacy of voriconazole (VRC) in a systemic infection by Trichosporon asahii in immunosuppressed guinea pigs. VRC was more effective than amphotericin B in prolonging survival and reducing tissue burden. The best results were obtained with VRC at 10 mg/kg of body weight/day.

Occurrence of Yeasts in Cloacae of Migratory Birds

Several species of yeast have been reported as pathogens in humans based on increases in immunodeficiency syndromes and as a result of immunosuppressant chemotherapy in cancer treatment. Domestic and wild birds are known to act as carriers of human pathogenic fungi. To gain additional information on the yeasts present in the cloacae of some species of migratory birds, 421 wild birds (24.39% out of 1726 birds caught in Romania, Hungary and Bulgaria) were sampled with the permission of the local judicial authority. The state of conservation of the birds (i.e. post-mortem alterations, colour of the mucosae etc.), along with their age and sex were determined. Samples were collected directly from the cloacae and cultured, and colonies were identified in each positive sample. Yeasts were isolated from 15.7% of the animals sampled, with the highest percentage found in coots (Fulica atra -58.8%) and the lowest in quails (Coturnix coturnix -1.7%). A total of 131 isolates belonging to 15 species of yeast were identified. Rhodotorula rubra was the yeast with the highest number of isolates (28.2%), followed by Cryptococcus albidus (18.4%), Candida albicans (9.2%), Trichosporon cutaneum (8.4%), Candida guilliermondii (6.1%), Candida tropicalis (6.1%) and other species. The present study represents the first survey on the occurrence of yeasts in the cloacae of migratory birds. The prevalence and species of yeasts isolated is discussed on the basis of the ecology, diet, and habitat of the birds.

Role of birds of prey as carriers and spreaders ofCryptococcus neoformansand other zoonotic yeasts

In the last 20 years, cases of human cryptococcosis, have increased in immunocompromised patients. In several instances, the cases have been associated with the exposure of the patients to bird droppings. In order to investigate birds of prey as potential carriers and spreaders of Cryptococcus neoformans and other yeasts of importance in human infections, 182 swab samples were collected from the cloacae of several species of birds of prey (Group I) and 32 faecal samples from aviaries in which the birds were housed (Group II). Samples were also taken from digestive tract of 60 dead birds (Group III). A total of 454 samples were cultured from which 215 colonies of yeastlike fungi were recovered and identified. Cryptococcusneoformans var. grubii was isolated from three cloacae samples (4.8%) collected from Falco tinnunculus and from one sample (3.1%) obtained from Buteo buteo, as well as from samples collected at the aviaries in which these birds were kept. Overall, 18 samples (9.9%) from Group I, 13 (40.6%) from Group II, 12 crops (20%), three proventriculi (5%) and 12 cloacae (20%) from Group III yielded positive cultures for yeasts. The results indicate that birds of prey and in particular, F. tinnunculus and B. buteo, may act as carriers and spreaders of C. neoformans and other zoonotic yeasts.

Invasive Saccharomyces infection: a comprehensive review

BACKGROUND

Saccharomyces cerevisiae (also known as "baker's yeast" or "brewer's yeast") is mostly considered to be an occasional digestive commensal. However, since the 1990s, there have been a growing number of reports about its implication as an etiologic agent of invasive infection. A particular feature of such infections is their association with a probiotic preparation of Saccharomyces boulardii (a subtype of S. cerevisiae) for treatment various diarrheal disorders.

METHODS

We collected published case reports, through May 2005, of invasive Saccharomyces infection by use of a Medline query. Epidemiological and clinical charts and therapeutic strategies were analyzed.

RESULTS

We found 92 cases of Saccharomyces invasive infection. Predisposing factors were similar to those of invasive candidiasis, with intravascular catheter and antibiotic therapy being the most frequent. Blood was the most frequent site of isolation (for 72 patients). S. boulardii accounted for 51.3% of fungemias and was exclusively isolated from blood. Compared with patients infected with S. cerevisiae, patients infected with S. boulardii were more frequently immunocompetent and had a better prognosis. Saccharomyces invasive infection was clinically indistinguishable from an invasive candidiasis. Overall, S. cerevisiae clinical isolates exhibited low susceptibility to amphotericin B and azole derivatives. However, global outcome was favorable in 62% of the cases. Treatment with intravenous amphotericin B and fluconazole, in combination with central vascular catheter removal, were effective therapeutic options.

CONCLUSION

Saccharomyces organisms should now be added to the growing list of emerging fungal pathogens. Special caution should be taken regarding the use of S. boulardii probiotic preparations.

Treatment of Non-Aspergillus Moulds in Immunocompromised Patients, with Amphotericin B Lipid Complex

An assessment was made of the efficacy and renal safety of amphotericin B lipid complex (ABLC) in the treatment of patients with invasive fungal infections caused by moulds other than Aspergillus species, on the basis of a retrospective analysis of data from the Collaborative Exchange of Antifungal Research (CLEAR) database. Data from CLEAR for 64 patients with zygomycosis were published previously. The database was further queried and yielded results for 28 patients with fusariosis and 84 patients infected with other non-Aspergillus moulds. Of 26 patients with fusariosis whose results could be evaluated, 46% (n = 12) were cured or improved, and an additional 12% (n = 3) were stable. Of 79 patients infected with other non-Aspergillus moulds whose results could be evaluated, 61% (n = 48) were cured or improved, and an additional 15% (n = 12) were stable. In an area with little guidance for therapy, the CLEAR data indicate that ABLC can be an effective broad-spectrum treatment choice for several invasive and refractory non-Aspergillus mould infections.

Saccharomyces cerevisiae fungemia: an emerging infectious disease

BACKGROUND

Saccharomyces cerevisiae is well known in the baking and brewing industry and is also used as a probiotic in humans. However, it is a very uncommon cause of infection in humans.

METHODS

During the period of 15-30 April 2003, we found 3 patients with S. cerevisiae fungemia in an intensive care unit (ICU). An epidemiological study was performed, and the medical records for all patients who were in the unit during the second half of April were assessed.

RESULTS

The only identified risk factor for S. cerevisiae infection was treatment with a probiotic containing Saccharomyces boulardii (Ultralevura; Bristol-Myers Squibb). This probiotic is used in Europe for the treatment and prevention of Clostridium difficile-associated diarrhea. The 3 patients received the product via nasograstric tube for a mean duration of 8.5 days before the culture result was positive, whereas only 2 of 41 control subjects had received it. Surveillance cultures for the control patients admitted at the same time did not reveal any carriers of the yeast. Strains from the probiotic capsules and the clinical isolates were identified as S. cerevisiae, with identical DNA fingerprinting. Discontinuation of use of the product in the unit stopped the outbreak of infection. A review of the literature identified another 57 cases of S. cerevisiae fungemia. Overall, 60% of these patients were in the ICU, and 71% were receiving enteral or parenteral nutrition. Use of probiotics was detected in 26 patients, and 17 patients died.

CONCLUSIONS

Use of S. cerevisiae probiotics should be carefully reassessed, particularly in immunosuppressed or critically ill patients.

Saccharomyces boulardii induced sepsis: successful therapy with voriconazole after treatment failure with fluconazole

Saccharomyces boulardii is frequently used for prevention and treatment of all forms of diarrhoea. We report the case of a 19-y-old white male with an underlying severe neurological disease, who developed a fungal sepsis after prophylactic application of a drug containing S. boulardii. Initial treatment with fluconazole was not successful. After the application of voriconazole, the sepsis resolved completely. This is the first clinical report of a successful treatment of Saccharomyces sepsis with voriconazole.

Efficacy of micafungin in combination with other drugs in a murine model of disseminated trichosporonosis

Using a murine model of disseminated infection caused by Trichosporon asahii, we have evaluated the efficacies of amphotericin B (AMB; 1 mg/kg of body weight/day), fluconazole (FLC; 20 mg/kg/twice a day), and micafungin (MFG; 5 mg/kg/twice a day). We tested these drugs alone and in combination (MFG with AMB and MFG with FLC). MFG with AMB showed a synergistic effect and demonstrated a higher degree of efficacy in prolonging survival and reducing the kidney fungal burden than either agent alone. The combination MFG with FLC was able to reduce significantly the kidney fungal burden in comparison to that achieved with either drug administered alone.

Mycological examinations on the fungal flora of the chicken comb

A total of 500 combs of adult chickens from two different locations in Germany (Hessen and Schleswig-Holstein) were clinically and mycologically examined. The chickens came from three battery cages (n = 79), one voliere system (n=32), six flocks maintained on deep litter (n = 69) and 12 flocks kept on free outdoor range (n=320). Twenty-two of the 500 chicken combs (4.4%) were found to have clinical signs: only non-specific lesions neither typical of mycosis nor of avian pox such as desquamation with crust formation, yellow to brown or black dyschromic changes, alopecia in the surrounding area and moist inflammation. Only seven of the 22 clinically altered combs showed a positive mycological result; the non-pathogenic and geophilic Trichophyton terrestre in one case and non-pathogenic yeast in six cases. The following fungi were seen in the different housing systems: 13 dermatophytes (2.6% of 500 samples): 12 x T. terrestre, 1 x Trichophyton mentagrophytes, 11 isolates of Chrysosporium georgiae (2.2% of 500 samples) and 149 isolates of yeasts (29.8%): Malassezia sympodialis: n = 52, Kloeckera apiculata: n = 33, Trichosporon capitatum (syn. Geotrichum capitatum): n = 23, Trichosporon cutaneum/Trichosporon mucoides: n = 12, Trichosporon inkin (syn. Sarcinosporon inkin): n = 8 and Candida spp.: n = 21, including pathogenic or possibly pathogenic species: Candida albicans: n = 3, Candida famata: n = 4, Candida guilliermondii: n = 3, Candida lipolytica: n = 3, Candida dattila: n = 2 and one isolate each of Candida glabrata, Candida parapsilosis, Candida aaseri, Candida catenulata sive brumpti, Candida fructus and Candida kefyr sive pseudotropicalis. There is no stringent correlation between the clinical symptoms diagnosed on the chicken combs and the species of yeasts isolated. The causative agent of favus in chickens, Trichophyton gallinae, and the saprophytic yeast in pigeons, Cr. neoformans were not isolated. The most frequently isolated yeasts M. sympodialis and Kloeckera apiculata are suggested to be classified as members of the resident flora of the chicken comb.

New agents for the treatment of systemic fungal infections – current status

Systemic antifungal chemotherapy is enjoying its most dynamic era. More antifungal agents are under development than ever before, including agents in entirely new classes. Major goals of current investigations are to identify compounds with a wide spectrum of activity, minimal toxicity and a high degree of target specificity. The antifungal drugs in development include new azoles {voriconazole, posaconazole (formerly SCH-56592), ravuconazole (formerly BMS-207147)}, lipid formulations of amphotericin B, a lipid formulation of nystatin, echinocandins {anidulafungin (formerly, LY-303366, VER-002), caspofungin (formerly MK-991), micafungin (formerly FK-463)}, antifungal peptides other than echinocandins, and sordarin derivatives. This discussion reviews the currently available antifungal agents and summarises the developmental issues that surround these new systemic antifungal drugs.

Saccharomyces cerevisiae fungemia in a head and neck cancer patient: a case report and review of the literature

We report the case of a 65-year old male who developed Saccharomyces cerevisiae fungemia after completing a course of concomitant chemotherapy and radiation therapy for head and neck carcinoma. He had grade IV oral mucositis, and received Saccharomyces boulardii (Perenterol) orally as treatment for aseptic diarrhoea just before the onset of fungemia. We discuss the epidemiology and pathology of Saccharomyces cerevisiae in the cancer patient population.

Disseminated trichosporonosis caused by Trichosporon loubieri

Trichosporonosis is an emerging invasive fungal infection in immunosuppressed patients; a case of disseminated infection caused by Trichosporon loubieri presented confirms its role as a human pathogen.