The emergence of fungi as major hospital pathogens

The Influence of Medium Composition on EUCAST and Etest Antifungal Susceptibility Testing

There is an ongoing effort to optimize and revise antifungal susceptibility testing (AFST) methods due to the rising number of fungal infections and drug-resistant fungi. The rising antifungal resistance within Candida and Aspergillus species, which are common contributors to invasive fungal infections (IFIs), is a cause for concern, prompting an expanding integration of in vitro AFST to guide clinical decisions. To improve the relevance of in vitro AFST results to therapy outcomes, influential factors should be taken into account. The tested medium is one of several factors that could affect the results of AFST. The present study evaluated the effect of two complex media (Sabouraud dextrose and Columbia) versus the standard defined medium (RPMI 1640) on the AFST results of amphotericin B, posaconazole, and voriconazole against Candida spp. and Aspergillus spp. representatives, utilizing the European Committee on Antimicrobial Susceptibility Testing (EUCAST) and the Etest methods. Overall, Candida species exhibited higher variability in minimum inhibitory concentration (MIC) across different media (more than three log2 dilutions) comparing to Aspergillus spp., while quality control isolates showed consistency regardless of tested media, antifungals, and methods. When comparing tested methods, MIC variation was mostly detected using EUCAST than it was using Etest.

Genome-wide piggyBac transposon-based mutagenesis and quantitative insertion-site analysis in haploid Candida species

Invasive fungal infections caused by Candida species are life threatening with high mortality, posing a severe public health threat. New technologies for rapid, genome-wide identification of virulence genes and therapeutic targets are urgently needed. Our recent engineering of a piggyBac (PB) transposon-mediated mutagenesis system in haploid Candida albicans provides a powerful discovery tool, which we anticipate should be adaptable to other haploid Candida species. In this protocol, we use haploid C. albicans as an example to present an improved version of the mutagenesis system and provide a detailed description of the protocol for constructing high-quality mutant libraries. We also describe a method for quantitative PB insertion site sequencing, PBISeq. The PBISeq library preparation procedure exploits tagmentation to quickly and efficiently construct sequencing libraries. Finally, we present a pipeline to analyze PB insertion sites in a de novo assembled genome of our engineered haploid C. albicans strain. The entire protocol takes ~7 d from transposition induction to having a final library ready for sequencing. This protocol is highly efficient and less labor intensive than alternative approaches and significantly accelerates genetic studies of Candida.

Evaluating of fungal contamination in hospital wet cooling systems in Markazi province, Central Iran

OBJECTIVE

Fungal infections are common complication among hospitalized patients especially between who is immunocompromised. Wet cooling systems in the hospital environment play a critical role as a source of these infections. The aim of this study was survey of wet cooling system of hospitals for fungal contamination in Arak city.

MATERIALS AND METHODS

This study was conducted during May to September of 2016. Sampling was done as random. Samples were obtained from water and straw of 84 wet cooling systems of four hospitals in Arak city. Samples were cultured in Sabouraud dextrose agar medium contain of chloramphenicol. Identification of fungi was performed by Slide culture method.

RESULTS

From 84 wet cooling systems, 32 (38.1%) were contaminated with fungi. The highest fungal contamination was found in wards of oncology and CCU. The most prevalent of fungi isolated in this study were Aspergillus spp. and Candida spp., respectively.

CONCLUSION

The findings of this descriptive cross-sectional study clearly indicate, in wards of the hospital that used wet cooling systems, there was considerable fungal contamination, particularly Aspergillus contamination. These results highlight a clear need for greater attention to the use of non-aqueous or closed circulation cooling systems, especially where susceptible patients receive medical care.

New Biofunctional Loading of Natural Antimicrobial Agent in Biodegradable Polymeric Films for Biomedical Applications

The study focuses on the development of novel Aloe vera based polymeric composite films and antimicrobial suture coatings. Polyvinyl alcohol (PVA), a synthetic biocompatible and biodegradable polymer, was combined with Aloe vera, a natural herb used for soothing burning effects and cosmetic purposes. The properties of these two materials were combined together to get additional benefits such as wound healing and prevention of surgical site infections. PVA and Aloe vera were mixed in a fixed quantity to produce polymer based films. The films were screened for antibacterial and antifungal activity against bacterial (E. coli, P. aeruginosa) and fungal strains (Aspergillus flavus and Aspergillus tubingensis) screened. Aloe vera based PVA films showed antimicrobial activity against all the strains; the lowest Aloe vera concentration (5%) showed the highest activity against all the strains. In vitro degradation and release profile of these films was also evaluated. The coating for sutures was prepared, in vitro antibacterial tests of these coated sutures were carried out, and later on in vivo studies of these coated sutures were also performed. The results showed that sutures coated with Aloe vera/PVA coating solution have antibacterial effects and thus have the potential to be used in the prevention of surgical site infections and Aloe vera/PVA based films have the potential to be used for wound healing purposes.

Synergic effect of combination of glycyrol and fluconazole against experimental cutaneous candidiasis due to Candida albicans

In this study, we investigated the anti-fungal activity of glycyrol, a coumarine isolated from licorice (Glycyrrhizae Radix), in a murine model of cutaneous candidiasis caused by Candida albicans. Compared to the infected sites, located on the mice's back, of the untreated control mice, the infected sites treated with glycyrol had reduced CFU (colony forming unit) values up to 60 and 85.5 % at 20 and 40 μg/mouse of glycyrol, respectively (P < 0.01). The antifungal activity of glycyrol was synergistically increased when glycyrol (10 μg/mouse) was combined with fluconazole (10 μg/mouse), demonstrating that the combination therapy is approximately 4 times more effective than fluconazole alone at 20 μg/mouse (P < 0.01). Additionally, the combination activity was 1.65 times greater than the antifungal activity of fluconazole alone at 40 μg/mouse (P < 0.05). In seeking glycyrol's antifungal mechanism, we determined that glycyrol inhibited hyphal induction and cell wall adherence of C. albicans. Thus, it is very likely that, by damaging the cell wall, glycyrol helps fluconazole invade C. albicans more readily and attack fluconazole's target in the fungus membrane. In summary, our data indicate that glycyrol may contribute to the development of a novel agent that possesses antifungal activity against cutaneous candidiasis.

Antifungal Activity of Bee Venom and Sweet Bee Venom against Clinically Isolated Candida albicans

OBJECTIVES

The purpose of this study was to investigate the antifungal effect of bee venom (BV) and sweet bee venom (SBV) against Candida albicans (C. albicans) clinical isolates.

METHODS

In this study, BV and SBV were examined for antifungal activities against the Korean Collection for Type Cultures (KCTC) strain and 10 clinical isolates of C. albicans. The disk diffusion method was used to measure the antifungal activity and minimum inhibitory concentration (MIC) assays were performed by using a broth microdilution method. Also, a killing curve assay was conducted to investigate the kinetics of the anti- fungal action.

RESULTS

BV and SBV showed antifungal activity against 10 clinical isolates of C. albicans that were cultured from blood and the vagina by using disk diffusion method. The MIC values obtained for clinical isolates by using the broth microdilution method varied from 62.5 μg/ mL to 125 μg/mL for BV and from 15.63 μg/mL to 62.5 μg/mL for SBV. In the killing-curve assay, SBV behaved as amphotericin B, which was used as positive control, did. The antifungal efficacy of SBV was much higher than that of BV.

CONCLUSION

BV and SBV showed antifungal activity against C. albicans clinical strains that were isolated from blood and the vagina. Especially, SBV might be a candidate for a new antifungal agent against C. albicans clinical isolates.

Ginsenoside Rd induces protective anti-Candida albicans antibody through immunological adjuvant activity

The role of an antibody against candidiasis is controversial. However, a certain Candida albicans surface epitope produces a protective antibody. Yet, its isolation is difficult. In this study, we investigated if ginsenoside Rd from Panax ginseng has an immunoadjuvant ability to induce surface mannan extract (CASM) to produce a protective antibody. Mice were immunized twice i.p. with an emulsion form of CASM mixed with one of the following: IFA [CASM/IFA], or CFA [CASM/CFA] or Rd with IFA [CASM/Rd/IFA]. One week after the booster, these mice were challenged i.v. with live C. albicans and their survivability was measured. Results showed that four of five CASM/Rd/IFA-vaccinated mice survived during the entire 110 day-observation period, whereas CASM/IFA- or CASM/CFA-vaccinated mice died within 19 and 23 days (P<0.05). The antiserum from CASM/Rd/IFA-immunized mice transferred the protection to naïve mice, whereas antiserum from CASM/CFA-given mice was not protective although CASM/CFA induced an antibody four times greater than CASM/Rd/IFA. IgG isotyping revealed that CASM/Rd/IFA-vaccine produced the most abundant IgG and IgG2a-resulting in the highest ratio (1.32) of IgG2a to IgG, which is helpful in treating Th2-oriented candidiasis. In contrast, the formulae lacking Rd had these ratios less than 1. This strongly indicates that Rd could enhance Th1 immunity. Cytokine profiles and DTH further confirmed the Th1 dominance. Rd caused no hemolysis. Combining all of these data together, Rd can enhance Th1-response to CASM in mice. This protects mice against disseminated candidiasis by eliciting higher titers of Th1 type antibody and a Th1-dominant immune response.

Pathogenic alteration in severe burn wounds

The present study aims to define the trend of time related changes with local bacterial alteration of bacterial resistance in severe burns in our burn center during a 12-year period. Retrospective analysis of microbiological results on severely burned wounds between 1998 and 2009 was carried out. A study of 3615 microbial isolates was performed. Staphylococcus aureus was the most commonly isolated pathogen (38.2%) followed by A. baumannii (16.2%), Streptococcus viridans (11.4%), Pseudomonas aeruginosa (10.4%), coagulase-negative staphylococci (CNS, 9.2%). The species ratios of S. aureus and A. baumannii increased significantly from 1st to 8th week of hospitalization, while those of Streptococcus viridans, P. aeruginosa and coagulase-negative staphylococci decreased during the same period. Bacterial resistance rates were compared between the periods 1998-2003 and 2004-2009. Vancomycin remained as the most sensitive antibiotic in S. aureus including methicillin-resistant S. aureus (MRSA). It was very likely that the majority of infections caused by Streptococcus viridans, P. aeruginosa and coagulase-negative staphylococci occurred in the early stage of burn course and the majority of infections caused by A. baumannii occurred 4 weeks after admission. The use of different antibiotics was probably the major contributor to these trends.

Diagnosis and therapy of Candida infections: joint recommendations of the German Speaking Mycological Society and the Paul-Ehrlich-Society for Chemotherapy

Invasive Candida infections are important causes of morbidity and mortality in immunocompromised and hospitalised patients. This article provides the joint recommendations of the German-speaking Mycological Society (Deutschsprachige Mykologische Gesellschaft, DMyKG) and the Paul-Ehrlich-Society for Chemotherapy (PEG) for diagnosis and treatment of invasive and superficial Candida infections. The recommendations are based on published results of clinical trials, case-series and expert opinion using the evidence criteria set forth by the Infectious Diseases Society of America (IDSA). Key recommendations are summarised here: The cornerstone of diagnosis remains the detection of the organism by culture with identification of the isolate at the species level; in vitro susceptibility testing is mandatory for invasive isolates. Options for initial therapy of candidaemia and other invasive Candida infections in non-granulocytopenic patients include fluconazole or one of the three approved echinocandin compounds; liposomal amphotericin B and voriconazole are secondary alternatives because of their less favourable pharmacological properties. In granulocytopenic patients, an echinocandin or liposomal amphotericin B is recommended as initial therapy based on the fungicidal mode of action. Indwelling central venous catheters serve as a main source of infection independent of the pathogenesis of candidaemia in the individual patients and should be removed whenever feasible. Pre-existing immunosuppressive treatment, particularly by glucocorticosteroids, ought to be discontinued, if feasible, or reduced. The duration of treatment for uncomplicated candidaemia is 14 days following the first negative blood culture and resolution of all associated symptoms and findings. Ophthalmoscopy is recommended prior to the discontinuation of antifungal chemotherapy to rule out endophthalmitis or chorioretinitis. Beyond these key recommendations, this article provides detailed recommendations for specific disease entities, for antifungal treatment in paediatric patients as well as a comprehensive discussion of epidemiology, clinical presentation and emerging diagnostic options of invasive and superficial Candida infections.

Diagnosing invasive fungal disease in critically ill patients

Fungal infections are increasing, with a changing landscape of pathogens and emergence of new groups at risk for invasive disease. We review current diagnostic techniques, focusing on studies in critically ill patients. Microbiological cultures, the current "gold standard", demonstrate poor sensitivity, thus diagnosis of invasive disease in the critically ill is difficult. This diagnostic dilemma results in under- or over-treatment of patients, potentially contributing to poor outcomes and antifungal resistance. While other current diagnostic tests perform moderately well, many lack timeliness, efficacy, and are negatively affected by treatments common to critically ill patients. New nucleic acid-based research is promising.

Combination immunotherapy of MAb B6.1 with fluconazole augments therapeutic effect to disseminated candidiasis

We recently reported that IgM MAb B6.1, specific for β-1, 2-mannotriose on the cell wall of Candida albicans, is therapeutic to disseminated candidiasis due to C. albicans. In the current study, we examined if MAbB6.1 enhances therapeutic effect of fluconazole (FLC) to the disseminated disease. To assess the combination effect, determination by the kidneys-colony forming unit and survival times were used. Results showed that the therapeutic effect of FLC on mice with disseminated candidiasis was dose-dependent, but a FLC dose at 0.8 mg/kg body weight of mice was ineffective. To determine combination effect, mice treated intraperitoneally with a combination of FLC plus MAb B6.1 at 1 h post-infection - a condition of developing partial therapeutic activity - enhanced survival times beyond the effect by only antibody (p < 0.05). The resulting MST (mean survival times) value from the combination-received mice was almost the same as MST value from 3.2 mg FLC dose-given animals (p < 0.05). Another combination of 1.6 mg FLC dose and B6.1 reduced severity of the disseminated disease at almost the same rate as combination efficacy of 0.8 mg FLC dose plus B6.1. This data indicates that B6.1 acts in concert with FLC and that this combination therapy augments protection, which suggests a possibility of reducing FLC dose. The augmentation response was specific because an irrelevant IgM MAb S9 was not effective to the disseminated disease. Thus, our present studies demonstrate that this combination immunotherapy may be a way of solving the problem of limited antifungal drug choices caused by drug-resistant C. albicans.

Inhibition of ergosterol synthesis by novel antifungal compounds targeting C-14 reductase

The limited number of clinically available antifungal drugs for life-threatening fungal infections has produced an increased demand for new agents. In the course of our screening for novel antifungals, we identified aminopiperidine derivatives which exhibit antifungal activities against the major pathogenic yeasts. Thin layer chromatography (TLC) analysis of the extracted non-saponifiable lipids from Candida albicans showed that these compounds inhibited the ergosterol production in the late step of the synthesis pathway. The results of an LC/Q-Tof MS analysis showed that abnormal sterols including predicted ignosterol, which is known to be accumulated in C. albicans ERG24 deleted mutant, were accumulated in C. albicans treated with one of these derivatives (Compound 1b). Furthermore, the partial disruption of the cell membrane of C. albicans treated with compound 1b was observed by electron microscopy analysis, suggesting its inhibition of ergosterol synthesis. Additionally, a genetic approach demonstrated that ERG24 gene would be responsible for the resistance of Saccharomyces cerevisiae against Compound 1b, strongly indicating that the enzyme targeted by Compound 1b is Erg24p. From all these data, we concluded that these aminopiperidine derivatives are novel antifungal compounds inhibiting C-14 reduction in the ergosterol synthesis pathway.

Nebulization of four commercially available amphotericin B formulations in persistently granulocytopenic rats with invasive pulmonary aspergillosis: evidence for long-term biological activity

The nebulization of amphotericin B desoxycholate (AMB-DOC), liposomal amphotericin B (L-AMB), amphotericin B lipid complex (ABLC) and amphotericin B colloidal dispersion (ABCD) has been investigated. Particle sizes of generated aerosol droplets were measured. Pulmonary amphotericin B deposition and amphotericin B concentration in blood directly after nebulization and at six weeks after nebulization was measured in healthy rats. The efficacy of nebulized amphotericin B formulations was evaluated in persistently granulocytopenic rats with invasive pulmonary aspergillosis. Treatment was given either after or before fungal inoculation. The endpoint was survival of animals. Aerosol particle sizes, expressed as the values for the mass median diameter were 1.38, 2.43, 0.90 and 2.29 μm for AMB-DOC, L-AMB, ABLC and ABCD, respectively. Amphotericin B concentrations in the lungs directly after nebulization exceeded the minimum inhibitory concentration of Aspergillus fumigatus and amphotericin B was still detected in lungs of rats at six weeks after nebulization. Treatment, started at 16 h after fungal inoculation, resulted in a significantly prolonged survival as compared with sham-treated rats for all four formulations. Prophylactic treatment at one week before fungal inoculation resulted in a significantly prolonged survival for all four formulations. Aerosol treatment given at two weeks before inoculation was effective only for AMB-DOC and L-AMB, whereas treatment given at six weeks resulted in a significantly prolonged survival for L-AMB only. All commercially available amphotericin B preparations could be nebulized efficiently and may be of value in the prophylactic treatment of invasive pulmonary aspergillosis.

Rutin has therapeutic effect on septic arthritis caused by Candida albicans

As of late, numerous reports have demonstrated the multiple biological activities of polyphenolic flavonoids. Amongst these reports, some indicate that the flavonoids play an important role in inflammation therapy. In this present study, we investigated the effect of rutin, a polyphenolic flavonoid, on septic arthritis due to Candida albicans, a major etiological agent that causes fungal arthritis. To induce septic arthritis, an emulsified mixture of C. albicans cell wall and Complete Freund's Adjuvant (CACW/CFA) was injected into BALB/c mice via hind footpad route once a day, everyday, for three days. In order to determine the effect of rutin, twenty-four hours after the final injection, mice having the swollen footpad were given the flavonoid (1 mg/dose/mouse) intraperitoneally every other day for three times. The footpad-edema was measured for a period of 17 days. Results showed that the rutin treatment reduced app. 45% of the edema at the peak day (day 11) of septic arthritis (P<0.05). In addition, 6 days after the peak, there was an app. 35% additional reduction of the edema (P<0.05). We found that this anti-arthritic activity was mediated by rutin's ability to inhibit nitric oxide production from macrophages and T-cells proliferation. Furthermore, this flavonoid also inhibited the growth of C. albicans yeast cells (P<0.01) and resulted in no hemolysis. These data indicate that rutin, which has both anti-arthritic and antifungal effects, can safely be administered into the blood circulation for treatment of septic arthritis caused by C. albicans. Ultimately, it can be suggested that the dual effects of rutin, anti-arthritic and anti-candidal may be helpful as an all-in-one treatment for septic arthritis.

Efficacy of caspofungin and posaconazole in a murine model of disseminated Exophiala infection

Disseminated phaeohyphomycosis is an uncommon infection affecting immunocompetent and immunocompromised individuals in which response to older antifungal agents has been variable. We compared the effect of six days of therapy with caspofungin, posaconazole, and amphotericin B in parallel studies of survival and fungal burden in an immunocompromised mouse model of Exophiala infection. Mice immunocompromised with cyclophosphamide were treated for 6 days starting one day after initiation of infection. Treatment regimens included amphotericin B, caspofungin, and posaconazole. In the survival studies, experimental animals were observed for 14 days. In the fungal burden tests the experimental animals were sacrificed 7 days after infection and brain and kidney burden determined. Treatment with any agent decreased mortality (P < 0.05), with 40%, 30%, and 80% observed survival of the animals treated with amphotericin B, caspofungin, and posaconazole, respectively. Amphotericin B and posaconazole treatment resulted in a decrease in fungal burden compared to untreated controls (P < 0.05). No reduction in fungal burden was noted in the caspofungin group. All three antifungals evaluated improved survival of immunocompromised mice in this otherwise fatal disseminated phaeohyphomycosis. Amphotericin B and posaconazole reduced fungal burden. Posaconazole and caspofungin appear to have potential for use in treatment of this rare infection.

Current status of antifungal susceptibility testing methods

Antifungal susceptibility testing is a very dynamic field of medical mycology. Standardization of in vitro susceptibility tests by the Clinical and Laboratory Standards Institute (CLSI) and the European Committee for Antimicrobial Susceptibility Testing (EUCAST), and current availability of reference methods constituted the major remarkable steps in the field. Based on the established minimum inhibitory concentration (MIC) breakpoints, it is now possible to determine the susceptibilities of Candida strains to fluconazole, itraconazole, voriconazole, and flucytosine. Moreover, utility of fluconazole antifungal susceptibility tests as an adjunct in optimizing treatment of candidiasis has now been validated. While the MIC breakpoints and clinical significance of susceptibility testing for the remaining fungi and antifungal drugs remain yet unclear, modifications of the available methods as well as other methodologies are being intensively studied to overcome the present drawbacks and limitations. Among the other methods under investigation are Etest, colorimetric microdilution, agar dilution, determination of fungicidal activity, flow cytometry, and ergosterol quantitation. Etest offers the advantage of practical application and favorable agreement rates with the reference methods that are frequently above acceptable limits. However, MIC breakpoints for Etest remain to be evaluated and established. Development of commercially available, standardized colorimetric panels that are based on CLSI method parameters has added more to the antifungal susceptibility testing armamentarium. Flow cytometry, on the other hand, appears to offer rapid susceptibility testing but requires specified equipment and further evaluation for reproducibility and standardization. Ergosterol quantitation is another novel approach, which appears potentially beneficial particularly in discrimination of azole-resistant isolates from heavy trailers. The method is yet investigational and requires to be further studied. Developments in methodology and applications of antifungal susceptibility testing will hopefully provide enhanced utility in clinical guidance of antifungal therapy. However, and particularly in immunosuppressed host, in vitro susceptibility is and will remain only one of several factors that influence clinical outcome.

Synergic effect of grape seed extract with amphotericin B against disseminated candidiasis due to Candida albicans

Amphotericin B (Amp B) is considered as a drug of choice for treatment of fungal infections, but it causes severe side effects such as renal damage. To lessen the severity, it is often combined with the azole, but data reporting resistance of Candida albicans to the azole have been recently increasing. Thus, finding a new product that can reduce Amp B dose by combination seems to be important. In the present study, we investigated a synergic effect of grape seed extract (GSE) combined with Amp B against the fungus. Our results showed that the GSE alone inhibited growth of C. albicans yeast cells, and that in a murine model of disseminated candidiasis mice groups given GSE before intravenous inoculation with the yeast cells survived longer than diluent-received (control) mice groups (P<0.05). This GSE antifungal effect was dose-dependent. Upon combination of GSE plus Amp B, the combination therapy strikingly retarded the yeast growth as determined by the broth susceptibility method. Against the disseminated disease, mice given diluent (negative control), Amp B (0.5mg/kg of body weight), or GSE (2mg/kg of body weight) had mean survival times (MSTs) of approximately 11.4, 14.4, and 17.6 days, respectively. However, mice treated with the combination of the doses of Amp B and GSE had a MST value of 38.4 days, surviving an average of 24 days longer than Amp B alone-treated mice groups. This MST value from the combination-received mice group was greater than the MST value from the mice group given four times the Amp B dose (2mg/kg of body weight). All these data indicate that the combination therapy can reduce more than 75% of Amp B dose, implying that GSE has a synergic effect with Amp B.

Synergic anticandidal effect of epigallocatechin-O-gallate combined with amphotericin B in a murine model of disseminated candidiasis and its anticandidal mechanism

In the present study, we investigated synergic anticandidal effect of epigallocatechin-O-gallate (EGCG) in a murine model of disseminated candidiasis caused by Candida albicans. In addition, its mechanism was examined. In the animal system, EGCG-given BALB/c mice group intraperitoneally (i.p.) before intravenous (i.v.) inoculation with viable C. albicans yeast cells survived longer than diluent-received (control) mice group (p<0.05). EGCG treatment inhibited the hyphal formation from the yeast form of C. albicans, causing growth-inhibition of the candidal cells. In experiments determining synergic effect, mice given diluent (control), Amp B (amphotericin B; 0.5 mg/kg of body weight), or EGCG (2 mg/kg) had mean survival times (MST) of approximately 10.9, 11.7, and 13.9 d, respectively. However, mice administered combination of Amp B (0.5 mg/kg) plus EGCG (2 mg/kg) had a MST value of 42.1 d, surviving an average of app. 30 d longer than the Amp B alone-received mice groups. The MST value from the combination-treated mice groups was much greater than MST value from mice groups that received four times the Amp B dose. These results indicate that EGCG, which has anticandidal activity causing blockage of the hyphal formation, has the synergism combined with Amp B against disseminated candidiasis.

Immunoregulatory activity by daucosterol, a β-sitosterol glycoside, induces protective Th1 immune response against disseminated Candidiasis in mice

In the present study, we investigated immunomodulatory effect of daucosterol, a beta-sitosterol glycoside, against disseminated candidiasis caused by Candida albicans. Results showed that direct interaction of daucosterol with C. albicans yeast cells resulted in no growth-inhibition by in vitro susceptibility analysis. In contrast, mice given daucosterol (DS) intraperitoneally before intravenous challenge with live C. albicans yeast cells survived longer than DS-untreated control mice against disseminated candidiasis (P<0.05). By assessment of the fungal CFU in kidneys, DS-treated mice before the challenge developed about 81% fewer kidney CFU than untreated controls. This protection was removable by pretreatment of mice with anti-CD4+ antibody before the DS-treatment and challenge with the yeast. However, the protection was transferable by the CD4+ T cells from DS-treated mice not infected with the yeast. ELISA analysis revealed there were predominant production of IFNgamma and IL-2 cytokines as compared to IL-4, and IL-10 productions in DS-treated mice. By treatment of DS-given mice with anti-mouse IFNgamma, the protection was also abolished. Our studies show that DS protects mice against disseminated candidiasis by the CD4+ Th1 immune response.

Candida pseudorugosa sp. nov., a novel yeast species from sputum

Two yeast strains, strains XH 1026 and XH 1164, isolated from the sputum of an intensive care unit patient with acute pneumonia, were originally identified as Candida albicans and C. tropicalis, respectively. Sequence analysis of the 26S rRNA gene D1/D2 domain and the internal transcribed spacer (ITS) region indicated that the two strains represent a novel yeast species closely related to C. rogusa. The name Candida pseudorugosa sp. nov. is therefore proposed (type strain, AS 2.3107 [CBS 10433]). The new species is able to grow at 42 degrees C and is resistant or insusceptible to amphotericin B (MIC, 2 microg/ml), caspofungin (MIC, 64 microg/ml), itraconazole (MIC, 1 microg/ml), and nystatin (MIC, 16 microg/ml); dose-dependent susceptible to fluconazole (MIC, 16 microg/ml); and susceptible to flucytosine (MIC, 0.125 microg/ml) and voriconazole (MIC, 0.125 to 0.25 microg/ml). The code for C. pseudorugosa sp. nov. provided by the API 20C AUX system is identical to that for C. rugosa. The colonies of the new species on CHROMagar Candida appear blue-green, similar to those of C. albicans. In addition to the molecular method based on D1/D2 domain or ITS region sequencing, use of the combination of the API system and CHROMagar Candida is helpful for the correct identification of C. pseudorugosa sp. nov.

Hybridoma passage in vitro may result in reduced ability of antimannan antibody to protect against disseminated candidiasis

We previously reported the enhanced resistance of monoclonal antibodies B6.1 (an immunoglobulin M [IgM]) and C3.1 (an IgG3) against experimental candidiasis. Both MAbs recognize the same fungal epitope. We have since found that a highly passaged B6.1 hybridoma (hp-B6.1) resulted in antibody that has little protective potential. The potential clinical applicability of the antibody and our interest in understanding antibody protection against candidiasis led us to investigate an explanation for this phenomenon. Antibody genetic structure of hp-B6.1, the original hybridoma clone (ori-B6.1) stored frozen since 1995, a subclone of hp-B6.1 that produces protective antibody, the IgG3-producing hybridoma, and a nonprotective IgG1-producing hybridoma were compared. Variable region gene sequences of heavy (V(H)) and light chains showed genetic instability of V(H) chains with only the hp-B6.1; the V(H) sequences from ori-B6.1 and the subclone were, however, identical. Activation-induced cytidine deaminase levels were greatest in the B6.1 hybridomas, which may explain the instability. The constant region CH3 domain remained unchanged, implying normal N-glycation and complement-fixing potential, and antibody binding affinities appeared unchanged. Complement fixation assays surprisingly showed that ori-B6.1 antibody fixes C3 more rapidly than does hp-B6.1 antibody. The V(H) region primary structure may affect complement activation, which could explain our result. Indeed, antibody from the hp-B6.1 subclone fixed complement like antibody from ori-B6.1. These results show that the greatest protection occurs when antimannan antibodies possess the dual abilities of recognizing the appropriate carbohydrate epitope and rapidly fixing complement; loss of the latter property results in the loss of protective potential by the antibody.

The efficiency of an air filtration system in the hospital ward

A study was conducted to ascertain the efficiency and effectiveness of an air filtration system (Electromedia Model 100C, Clean Air UK, UK) in the hospital ward. The sampling was conducted using a portable Surface Air Sampler (Cherwell Laboratories, Bicester, UK) in conjunction with settle plates. Samples were taken two days before and two days following activation of the filtration system and results compared. A clear, demonstrable, statistically significant reduction in microbial organisms following the activation of the filtration systems is evident (81% settle plates; 24% Surface Air Sampler). This study has implications for the improved health and welfare of patients and healthcare workers who may benefit through the implementation of such a system.

Ginsenoside Rg1 helps mice resist to disseminated candidiasis by Th1 type differentiation of CD4+ T cell

Ginsenosides, the most important component isolated from Panax ginseng, exhibits a variety of biological activities. Particularly, ginsenoside Rg1 is known to have various immune-modulating activities such as increase of immune activity of T helper (Th) cells. In this present work, we investigated the effect of the Rg1 on Candida albicans growth. Results showed that direct interaction of the Rg1 to C. albicans yeast cells resulted in no growth inhibition as tested by agar diffusion susceptibility method. Reversely, mice given the Rg1 intraperitoneally (i.p.) before intravenous (i.v.) challenge with live C. albicans yeast cells protected the mice to experimental disseminated candidiasis. By kidney candidal CFU (colony forming unit) determination, the disease severity of the Rg1-treated mice was confirmed far less than Rg1-untreated control mice. The protection was transferable by CD4+ T cells (RGCD4T) isolated from Rg1-treated mice. ELISA analysis revealed that there were cytokine inductions of IFNgamma, IL-2, IL-4 and IL-10 from the RGCD4T, demonstrating the Th1-lineage development of predominant IFNgamma and IL-2 production. Anti-mouse IFNgamma antibody treatment of Rg1-treated mice abolished the protection to disseminated disease. Our studies show that ginsenoside Rg1 helps the host resists disseminated candidiasis by the CD4(+) T cell-mediated immune response led from a Th1-dominant cytokine response.

Visualizing fungal infections in living mice using bioluminescent pathogenic Candida albicans strains transformed with the firefly luciferase gene

Animal studies with Candida albicans have provided models for understanding fungal virulence and antifungal drug development. To non-invasively monitor long-term Candida murine infections, clinical isolates were stably transformed with a codon-optimized luciferase gene to constitutively express luciferase. Chronic systemic infections were established in mice with engineered strains, and bioluminescent signals were apparent from kidneys by non-invasive imaging using charged-coupled device cameras. These infections were established in immune-competent mice, and bioluminescence was detectable in animals that showed no physiological consequence of infection, as well as those visually succumbing to the disease. Similarly, bioluminescence was measured from the vaginal tissue of mice infected vaginally. Fungal loads determined by plating vaginal lavages showed a similar pattern to the bioluminescent signals measured, and fungal infection could be detected in animals for over 30 days post infection by both modalities. The effect of the antifungal drug miconazole was tested in this model, and clearance in animals was apparent by both direct imaging and fungal load determination. The use of bioluminescence to monitor these and other models of Candida infections will greatly speed up the analysis of drug development studies, both in ease of visualizing infections and decreasing numbers of animals required to run such studies.

Nonfatal pulmonary Trichoderma viride infection in an adult patient with acute myeloid leukemia: report of one case and review of the literature

Trichoderma species have been recognized to be pathogenic in immunosuppressed hosts with increasing frequency. Trichoderma species are responsible for continuous ambulatory peritoneal dialysis associated peritonitis and infections in immunocompromised patients with a hematologic malignancy or solid organ transplantation. Trichoderma longibrachiatum is the most common species involved in these infections. We report the first case of nonfatal pulmonary infection caused by Trichoderma viride in leukemia patient. It had a successful answer to new antifungal agents as voriconazole and caspofungin. Trichoderma viride was isolated from pulmonary aspirate culture from a 54-year-old female who had received chemotherapy for acute myeloid leukemia. The minimal inhibitory concentrations for the organism were the following: amphotericin B (0.25 microg/mL) and voriconazole (2 microg/mL). Initially, she was treated unsuccessful with liposomal amphotericin B and voriconazole and caspofungin were added later. The patient is alive. We report one case along review of the literature.

Ginkgo terpene component has an anti-inflammatory effect on Candida albicans-caused arthritic inflammation

The Ginkgo biloba extract, EGb 761, contains flavonoid glycosides and unique terpene lactones as major active components. In this study, we determined the anti-inflammatory effect of the water-soluble portion (GH415) of the EGb 761 on the inflammation caused by Candida albicans, a major ethiological agent that causes fungal arthritis. For inflammatory induction, an emulsified mixture of C. albicans cell wall and Complete Freund's Adjuvant (CACW/CFA) was injected into BALB/c mice by the hind footpad route once a day for 3 days. Twenty-four hours after the final injection, mice having the swollen footpad were given the GH415 (2 mg/dose) intraperitoneally to the mice once every 3 days for 15 days. The footpad-swelling of these mice was measured during the entire observation period. Results showed that the GH415 treatment reduced the swelling. In the same animal model, this effect was enhanced by treatment with the GH415 entrapped within liposome (Lipo-GH: 200 micro/dose). Further analysis revealed that terpene, not flavone portion, was responsible for such therapeutic anti-inflammatory effect. Treatment with the terpene (7.4 microg/dose) by liposomal delivery method had similar effects as the treatment with indomethacin at 30 microg/dose. Addition of the terpene to lipopolysaccharide-treated macrophages showed suppression of nitric oxide (NO) production. These results suggest that blockage of the NO production from the macrophages that infiltrated to the inflamed site may be a possible mechanism for the therapeutic anti-inflammatory effect.

Berberine Synergy with Amphotericin B against Disseminated Candidiasis in Mice

In present study, we investigated the synergic effect of berberine against disseminated candidiasis caused by the pathogenic fungus, Candida albicans. Berberine inhibited the growth of C. albicans under in-vitro condition. The broth susceptibility revealed the synergic effect of berberine with amphotericin B (Amp B). To confirm these results under the in-vivo condition, the effect was examined in mice against disseminated candidiasis. Results showed mice that were given diluent (negative control), Amp B (0.5 mg/kg of body weight), or berberine (1 mg/kg of body weight) had mean survival times (MST) of approximately 12, 14, and 17 d, respectively. On the contrary, mice that were treated using a combination of the two agents at the same concentrations resulted in a MST value of 36 d, surviving at an average of 22 d longer than the mice group treated only with the Amp B. This MST value was almost same as MST value from the mice that were given four times the Amp B dose. These data indicate that the combination of Amp B and berberine could reduce approximately 75% of the Amp B dose, implying that berberine indeed has synergy with Amp B against the disseminated disease.

Detection of Candida in concentrated oral rinse cultures by real-time PCR

The incidence of oral candidosis has increased in recent years, largely as a result of the emergence of human immunodeficiency virus infection and the more widespread use of immunosuppressive chemotherapy. This development has been associated with a need for more reliable methods for the detection of Candida. The present study assessed the performance of a real-time PCR and two block-based PCRs for the detection of Candida in 193 concentrated oral rinse culture (CRC) specimens. A total of 102 CRC specimens were positive by culture for Candida; and 96, 90, and 75 of these were also positive by real-time, N18-specific, and internal transcribed spacer (ITS)-specific PCRs, respectively. The five false-negative results by the real-time PCR were all non-Candida albicans positive by culture. Of the 91 culture-negative CRC specimens, 20, 41, and 44 were positive by the real-time PCR and the N18- and ITS-specific PCRs, respectively. All three PCRs detected fungal DNA in 8 culture-negative CRC specimens, with a further 30 being positive by two of the three PCRs. A total of 32 CRC specimens were Candida free by all methods. In summary, a real-time PCR that provides a sensitive, specific, and rapid alternative technique for detection of Candida in the mouth is described.

A survey on the pathogenic fungi in soil samples of potted plants from Sari hospitals, Iran

A total of 23 soil samples of potted plants was collected from hospitals in Sari, Iran. Each sample contained approximately 200 g soil, taken from a depth of 0-10 cm of the pots. Samples were analysed by two different methods. (1) Culture on Sabouraud's dextrose agar medium containing chloramphenicol (SC); cultured fungi were identified by macroscopic and microscopic characterization. (2) The hair-baiting technique (HBT) was used to isolate the keratinophilic fungi. After culture on SC medium, 100% of plates were positive for fungal growth, and in total 1150 colonies with 13 different types of fungi were isolated. Penicillium spp. (52%), Acremonium spp. (20%), Paecilomyces spp. (11.9%), Cladsporium spp. (3.7%) and Aspergillus spp. (3.1%) were the predominant fungal species. Rhizopus spp. (0.1%) were less frequent. Keratinophilic fungi such as Microsporum gypseum, Microsporum cookei and Chrysosporium spp. were isolated using HBT. The presence of pathogenic fungi such as Cladosporium spp, Aspergillus spp, M. gypseum, and M. cookei in potted plants in hospitals represents a potential source of nosocomial infection.

Fungal metabolite gliotoxin inhibits assembly of the human respiratory burst NADPH oxidase

Reactive oxygen species are a critical weapon in the killing of Aspergillus fumigatus by polymorphonuclear leukocytes (PMN), as demonstrated by severe aspergillosis in chronic granulomatous disease. In the present study, A. fumigatus-produced mycotoxins (fumagillin, gliotoxin [GT], and helvolic acid) are examined for their effects on the NADPH oxidase activity in human PMN. Of these mycotoxins, only GT significantly and stoichiometrically inhibits phorbol myristate acetate (PMA)-stimulated O2- generation, while the other two toxins are ineffective. The inhibition is dependent on the disulfide bridge of GT, which interferes with oxidase activation but not catalysis of the activated oxidase. Specifically, GT inhibits PMA-stimulated events: p47phox phosphorylation, its incorporation into the cytoskeleton, and the membrane translocation of p67phox, p47phox, and p40phox, which are crucial steps in the assembly of the active NADPH oxidase. Thus, damage to p47phox phosphorylation is likely a key to inhibiting NADPH oxidase activation. GT does not inhibit the membrane translocation of Rac2. The inhibition of p47phox phosphorylation is due to the defective membrane translocation of protein kinase C (PKC) betaII rather than an effect of GT on PKC betaII activity, suggesting a failure of PKC betaII to associate with the substrate, p47phox, on the membrane. These results suggest that A. fumigatus may confront PMN by inhibiting the assembly of the NADPH oxidase with its hyphal product, GT.

Influence of building construction work on Aspergillus infection in a hospital setting

BACKGROUND AND OBJECTIVE

Aspergillus fumigatus is a major pathogen causing nosocomial infections. Hospital outbreaks of invasive aspergillosis have been associated with the renovation and construction of buildings. Building construction work for fire safety upgrading was undertaken during a 16-week period in 2001 at Box Hill Hospital. This study was designed to examine the effect of construction on invasive aspergillosis when using standard and additional protective measures.

METHODS

Baseline air sampling was conducted in 18 areas. The validity of the air sampling was assessed by comparing the ability of two air samplers to detect Aspergillus conidia. Surveillance of nosocomial Aspergillus infection was conducted by reviewing the records of patients with a sputum culture positive for Aspergillus and those prescribed amphotericin or itraconazole for the period of construction activity and the same period the previous year.

RESULTS

Aspergillus was isolated infrequently and there was no statistically significant difference in the levels of viable pathogenic fungi between areas w here construction work was undertaken and areas where it wasnot undertaken. A moderate agreement was observed between the two air samplers (kappa = 0.4; P < .05). There was no difference in the incidence of invasive aspergillosis between 2000 and 2001 (incidence density ratio, 1.2; 95% confidence interval, 0.3 to 4.1).

CONCLUSION

The influence of construction work performed with protective measures needs to be examined in an environment with higher levels of airborne fungi to confirm the findings of this study.

Isolation of an unusual fungus in treated dental unit waterlines

BACKGROUND

Numerous organisms have been identified in dental unit waterlines, or DUWLs. Decontamination of DUWLs focuses on maintaining heterotrophic, mesophilic bacteria below 200 colony-forming units per milliliter as recommended by the ADA.

METHODS

The authors conducted a study to test the efficacy of a continuous-use, stabilized chlorine dioxide proprietary compound to decrease the number of bacteria in DUWLs. The authors used three dental units with self-contained water systems to test the product and three similar units as controls. They aseptically collected water samples weekly according to recommended methods, plated the samples on R2A agar and incubated them for seven days.

RESULTS

The authors isolated heterotrophic, mesophilic bacteria from treatment and control units for eight weeks. In the ninth week, the predominant isolates from one of the treatment units changed in appearance to small, dark, shiny colonies that the authors tentatively identified as fungal. The authors then isolated similar colonies from the source tap water and ultrasonic and handpiece lines. They added three additional dental units from the same clinic in the sixth week of the study and isolated similar fungal colonies from them after five weeks of treatment. The authors performed DNA sequencing with an automated sequencer and identified the organism Exophiala mesophila.

CONCLUSIONS

The authors did not observe fungal isolates in the control units, which suggests that continuous waterline treatment may cause proliferation of a fungus present in small amounts in source water. CLINICAL IMPLICATIONS. The findings of this study indicate the need to monitor water quality regularly when treating waterlines with continuous-use chemical cleaners.

Evaluation of antimicrobial agents using an experimental pulmonary superinfection model with Aspergillus fumigatus and Pseudomonas aeruginosain leukopenic mice

The therapeutic efficacy of amphotericin B (AmB), imipenem/cilastatin (IPM/CS), pazufloxacin (PZFX) mesilate, and combinations of these, was evaluated using an experimental pulmonary superinfection model in mice caused by Pseudomonas aeruginosa and Aspergillus fumigatus. The superinfected mice died within 3 days. Although the viable cell count of P. aeruginosa increased markedly from 10(3) to 10(8) CFU/lung on day 2 after infection, that of A. fumigatus decreased from 10(3) to 10(2) CFU/lung on that day, showing that P. aeruginosa facilitated the mortality in the superinfection. Extensive necrosis in the lung parenchyma and moderate hyphae proliferation of A. fumigatus were observed on day 2 after infection. Mice treated with PZFX mesilate (50 mg/kg per day) and the combination of PZFX mesilate (50 mg/kg per day) - AmB (2.5 mg/kg per day) showed prolonged survival in comparison to untreated control mice ( P < 0.05). In the PZFX mesilate-treated group, no significant necrosis was observed, but necrosis due to the hyphae proliferation of A. fumigatus was still observed in the lung parenchyma on day 6 after infection. However, neither significant necrosis nor hyphae proliferation of A. fumigatus was observed in mice treated with the combination of PZFX mesilate - AmB. On the other hand, the survival rates of mice treated with AmB (2.5 mg/kg per day), IPM/CS (50 mg/kg per day), and the IPM/CS-AmB combination were all less than 10%. The viable cell count of P. aeruginosa decreased in PZFX mesilate-alone group and in the combination of PZFX mesilate - AmB group, but no significant decrease in this count was observed in the IPM/CS and combination of IPM/CS-AmB group. The viable count of A. fumigatus was increased in the IPM/CS, PZFX mesilate-alone, and combination of IPM/CS-AmB groups, but the count was suppressed in the AmB-alone and the combination of PZFX mesilate - AmB group. In conclusion, this superinfection model would be useful to evaluate the therapeutic potential of combinations of antibacterial and antifungal agents, and the scheduling of drug administration in terminal infections caused by P. aeruginosa and A. fumigatus.

Site-directed mutational analysis of the novel catalytic domains of alpha-aminoadipate reductase (Lys2p) from Candida albicans

The alpha-aminoadipate reductase, a novel enzyme in the alpha-aminoadipic acid pathway for the biosynthesis of lysine in fungi, catalyzes the conversion of alpha-aminoadipic acid to alpha-aminoadipic-delta-semialdehyde in the presence of ATP, NADPH and MgCl(2). This reaction requires two distinct gene products, Lys2p and Lys5p. In the presence of CoA, Lys5p posttranslationally activates Lys2p for the alpha-aminoadipate reductase activity. Sequence alignments indicate the presence of all functional domains required for the activation, adenylation, dehydrogenation and alpha-aminoadipic acid binding in the Lys2p. In this report we present the results of site-directed mutational analysis of the conserved amino acid residues in the catalytic domains of Lys2p from the pathogenic yeast Candida albicans. Mutants were generated in the LYS2 sequence of pCaLYS2SEI by PCR mutagenesis and expressed in E. coli BL21 cells. Recombinant mutants and the wild-type Lys2p were analyzed for their alpha-aminoadipate reductase activity. Substitution of threonine 416, glycine 418, serine 419, and lysine 424 of the adenylation domain (TXGSXXXXK, residues 416-424) resulted in a significant reduction in alpha-aminoadipate reductase activity compared to the unmutagenized Lys2p control. Similarly replacement of glycine 978, threonine 980, glycine 981, phenylalanine 982, leucine 983 and glycine 984 of the NADPH binding domain (GXTGFLG, residues 978-984) caused a drastic decrease in alpha-aminoadipate reductase activity. Finally, substitution of histidine 460, aspartic acid 461, proline 462, isoleucine 463, glutamine 464, arginine 465, and aspartic acid 466 of the putative alpha-aminoadipic acid binding domain (HDPIQRD, residues 460-466) resulted in a highly reduced alpha-aminoadipate reductase activity. These results confirm the hypothesis that specific amino acid residues in highly conserved catalytic domains of Lys2p are essential for the alpha-aminoadipate reductase activity.

Evaluation of a polymerase chain reaction reverse hybridization line probe assay for the detection and identification of medically important fungi in bronchoalveolar lavage fluids

An assay system in which polymerase chain reaction (PCR) amplification of the ITS-1 region of ribosomal DNA (rDNA) is combined with a reverse-hybridization line probe assay (LiPA) was used for the identification of six Candida species and four Aspergillus species in pure cultures of clinical isolates, as well as in bronchoalveolar lavage (BAL) fluid samples from 42 patients with various underlying diseases. The results were compared with the results obtained with conventional routine identification methods as well as with a commercial enzyme-linked immunosorbent assay (ELISA) galactomannan detection assay and an Aspergillus-specific PCR. No discrepancies between the PCR-LiPA system and routine methods were found for pure cultures of Candida and Aspergillus species except in the case of Aspergillus versicolor. In BAL fluid samples in which Candida species were cultured, the PCR-LiPA system identified more species than did the routine methods. When routine analyses of patient samples were supplemented by adding data obtained by repurifying and re-identifying cultures and by taking isolates obtained from other body sites into account, the results agreed with PCR-LiPA system results in 81% of the cases (34/42). Most of the remaining discrepancies (6/8) involved cases in which such supplementary data were not available. In BAL fluid samples from which A. fumigatus was cultured, the agreement between the PCR-LiPA system and the routine methods was low. Only 2 of 11 BAL samples shown to contain A. fumigatus in ELISA and genus-specific PCR assays were positive in PCR-LiPA system. The PCR-LiPA system enables the simultaneous detection and identification of different fungal species present in pure or mixed populations within 6 h in a single assay. Optimization is required, however, before it is useful as a diagnostic tool in the clinical microbiology laboratory.

Nosocomial outbreak of Exophiala jeanselmei fungemia associated with contamination of hospital water

From December 1996 through September 1997, we diagnosed 19 cases of fungemia due to Exophiala jeanselmei. We conducted a matched case-control study in which we cultured specimens of blood products, intravenous solutions, and water from a hospital water system. Isolates from environmental cultures were compared to those recovered from patients by random amplification of polymorphic DNA (RAPD). Multivariate analysis showed that neutropenia, longer duration of hospitalization, and use of corticosteroids were risk factors for infection. Environmental cultures yielded E. jeanselmei from 3 of 85 sources: deionized water from the hospital pharmacy, 1 water tank, and water from a sink in a non-patient care area. Use of deionized pharmacy water to prepare antiseptic solutions was discontinued, and no additional cases of infection occurred. RAPD typing showed that isolates from case patients and isolates from the pharmacy water were highly related, whereas the patterns of isolates recovered from the 2 other sources of water were distinct.

Uncommon opportunistic fungi: new nosocomial threats

During the past two decades opportunistic fungal infections have emerged as important causes of morbidity and mortality in patients with severe underlying illnesses and compromised host defenses. While Aspergillus and Candida spp. collectively account for the majority of these infections, recent epidemiological trends indicate a shift towards infections by Aspergillus spp., nonalbicans Candida spp., as well as previously uncommon opportunistic fungi. Apart from an expanding number of different Zygomycetes, previously uncommon hyaline filamentous fungi (such as Fusarium species, Acremonium species, Paecilomyces species, Pseudallescheria boydii, and Scedosporium prolificans), dematiaceous filamentous fungi (such as Bipolaris species, Cladophialophora bantiana, Dactylaria gallopava, Exophiala species, and Alternaria species) and yeast-like pathogens (such as Trichosporon species, Blastoschizomyces capitatus, Malassezia species, Rhodotorula rubra and others) are increasingly encountered as causing life threatening invasive infections that are often refractory to conventional therapies. On the basis of past and current trends, the spectrum of fungal pathogens will continue to evolve in the settings of an expanding population of immunocompromised hosts, selective antifungal pressures, and shifting conditions in hospitals and the environment. An expanded and refined drug arsenal, further elucidation of pathogenesis and resistance mechanisms, establishment of in vitro/in vivo correlations, incorporation of pharmacodynamics, combination- and immunotherapies offer hope for substantial progress in prevention and treatment.

[Hormonal contraception and epilepsy]

Attempts to optimize quality of life in woman with epilepsy should include a reliable method for birth control, including oral contraceptives (OC). One of these methods is hormonal oral contraception. The classic antiepileptic drugs (AEDs)--Phenytoin, Phenobarbital, Ethosuximide and Carbamazepine induce hepatic microsomal enzymes and decrease the production of estradiol and progesterone, that may be compromise the effects of OC. Recommendation for women taking OC include possible use of noninducing AEDs (Valproic acid), new AEDs--Lamotrigine, Gabapentin, Topiramate, Tiagabine or for patients taking inducing AEDs use of an OC containing > or = 50 micrograms. estrogen. Patients should be warned that midcycle bleeding indicates possible OC failure and that the absence of such bleeding is not an indication of OC effectiveness. Additional contraceptive methods are also advised. The authors report their own experience in 12 women taking AEDs and OC.

A prospective and retrospective analysis of the nephrotoxicity and efficacy of lipid-based amphotericin B formulations

STUDY OBJECTIVE

To determine the usage patterns of the lipid-based amphotericin B formulations at our institution and to compare the observed nephrotoxicity and efficacy of these formulations.

DESIGN

Prospective and retrospective observational study

SETTING

Urban 350-bed teaching hospital.

PATIENTS

Sixty-seven nonhemodialysis patients who were prescribed greater than 3 days of amphotericin B lipid complex (ABLC) or liposomal amphotericin B (L-AmB) from 1996-1999.

MEASUREMENTS AND RESULTS

Forty-six patients received ABLC and 21 received L-AmB. Oncology patients accounted for most prescriptions of both formulations. Amphotericin B lipid complex most frequently was prescribed for treatment of documented fungal infections (50%), followed by treatment of neutropenic fever (33%). Liposomal amphotericin B most frequently was prescribed for treatment of neutropenic fever (62%), followed by treatment of documented fungal infections (29%). Seventy-eight percent of patients treated with ABLC and 90% of those who received L-AmB were started on the lipid-based formulation due to being refractory or intolerant to prior antifungal therapy. Two (4.4%) patients receiving ABLC and four (19%) patients receiving L-AmB experienced nephrotoxicity at the end of therapy (NS). Of the patients with a documented fungal infection, 20 out of 23 (87%) of those treated with ABLC and 4 out of 5 (80%) of those treated with L-AmB had a complete or partial response to therapy (NS). One patient with febrile neutropenia had a breakthrough fungal infection while receiving L-AmB.

CONCLUSION

No significant differences in nephrotoxicity or efficacy were found between ABLC and L-AmB. Until further studies indicate clinically significant differences in nephrotoxicity between the two liposomal amphotericin B formulations, it is recommended that economics continue to be the major determinant for product selection.