Study on the bacteriostatic action of Chinese herbal medicine on avian Trichosporon.

In this study, a strain of Trichosporon was isolated from white pseudomembranes and ulcers formed on mucous membranes of pigeon bursas and was identified through gene sequencing. Bacteriostatic actions of Acorus gramineus, Sophora flavescens, Polygonum hydropiper, and Chinese herbal mixture on this species were explored in vitro, and the minimum inhibitory concentration of herbal medicines against Trichosporon was determined through microdilution method. Therapeutic effects of herbal medicines on chickens infected by Trichosporon were studied, whose results showed that minimum inhibitory concentration of A. gramineus was 32 µg/µL, that of S. flavescens was 2 µg/µL, that of P. hydropiper was 120 µg/µL, and that of Chinese herbal mixture was 36 µg/µL. Antibacterial effects of S. flavescens were the best. In accordance with animal experiments, therapeutic effects of Chinese herbal medicines on infected chickens were better than those of fluconazole. The mortality rate of the Chinese herbal medicine treatment group was 33.33%, that of the fluconazole treatment group was 46.67%, and that of the Chinese medicine protection group was 23.33%. The longer the time of Chinese medicine treatments was, the better the treatment effects would be. Glutamic oxaloacetylase values of the serum and liver in the Chinese herbal medicine treatment group were both significantly lower than those of the nontreatment group. From the results, it can be seen that A. gramineus, S. flavescens, P. hydropiper, and Chinese herbal mixture have certain inhibitory effects on Trichosporon spp. Chinese herbal medicine protections in advance could reduce Trichosporon infections.

Sodium butyrate inhibits planktonic cells and biofilms of Trichosporon spp.

Trichosporon spp. have been increasingly recognized as an important pathogen of invasive and disseminated infections in immunocompromised patients. These species are prone to form biofilms in medical devices such as catheters and prosthesis, which are associated with antifungal resistance and therapeutic failure. Therefore, new antifungals with a broader anti-biofilm activity need to be discovered. In the present study we evaluate the inhibitory potential of sodium butyrate (NaBut) - a histone deacetylase inhibitor that can alter chromatin conformation - against planktonic and sessile cells of T. asahii and T. inkin. Minimum inhibitory concentration (MIC) of NaBut against planktonic cells was evaluated by microdilution and morphological changes were analyzed by optical microscopy on malt agar supplemented with NaBut. Biofilms were evaluated during adhesion, development and after maturation for metabolic activity and biomass, as well as regarding ultrastructure by scanning electron microscopy and confocal laser scanning microscopy. NaBut inhibited the growth of planktonic cells by 50% at 60 mM or 120 mM (p < 0.05) and also reduced filamentation of Trichosporon spp. NaBut reduced adhesion of Trichosporon cells by 45% (10xMIC) on average (p < 0.05). During biofilm development, NatBut (10xMIC) reduced metabolic activity and biomass up to 63% and 81%, respectively (p < 0.05). Mature biofilms were affected by NaBut (10xMIC), showing reduction of metabolic activity and biomass of approximately 48% and 77%, respectively (p < 0.05). Ultrastructure analysis showed that NaBut (MIC and 10xMIC) was able to disassemble mature biofilms. The present study describes the antifungal and anti-biofilm potential of NaBut against these opportunist emerging fungi.

In vitro activity of diphenyl diselenide and ebselen alone and in combination with antifungal agents against Trichosporon asahii.

This study evaluated the in vitro susceptibility of Trichosporon asahii strains to diphenyl diselenide (DPDS) and ebselen (EBS) alone and in combination with amphotericin B (AMB), fluconazole (FCZ), itraconazole (ITZ) and caspofungin (CAS) using the microdilution method. EBS showed in vitro activity against T asahii strains with minimal inhibitory concentration (MIC) ranged from 0.25 to 8.0 µg/mL. For DPDS, the MIC ranged from 8.0 to 64 µg/mL. The combinations demonstrating the greatest synergism rate against fluconazole-resistant T asahii strains were the following: CAS + DPDS (96.67%), AMB + DPDS (93.33%), FCZ + DPDS (86.67%) and ITZ + DPDS (83.33%). The combinations AMB + DPDS and AMB + EBS exhibited the highest synergism rate against the fluconazole-susceptible (FS) T asahii strains (90%). Antagonism was observed in the following combinations: FCZ + EBS (80%) and FCZ + DPDS (13.33%) against the FS strains, and ITZ + EBS (20%) against the FR strains. Our findings suggest that the antimicrobial activity of DPDS and EBS against T. asahii and its use as an adjuvant therapy with antifungal agents warrant in vivo experimental investigation.

Effect of resveratrol and Regrapex-R-forte on Trichosporon cutaneum biofilm.

Microorganisms that cause chronic infections exist predominantly as surface-attached stable communities known as biofilms. Microbial cells in biofilms are highly resistant to conventional antibiotics and other forms of antimicrobial treatment; therefore, modern medicine tries to develop new drugs that exhibit anti-biofilm activity. We investigated the influence of a plant polyphenolic compound resveratrol (representative of the stilbene family) on the opportunistic pathogen Trichosporon cutaneum. Besides the influence on the planktonic cells of T. cutaneum, the ability to inhibit biofilm formation and to eradicate mature biofilm was studied. We have tested resveratrol as pure compound, as well as resveratrol in complex plant extract-the commercially available dietary supplement Regrapex-R-forte, which contains the extract of Vitis vinifera grape and extract of Polygonum cuspidatum root. Regrapex-R-forte is rich in stilbenes and other biologically active substances. Light microscopy imaging, confocal microscopy, and crystal violet staining were used to quantify and visualize the biofilm. The metabolic activity of biofilm-forming cells was studied by the tetrazolium salt assay. Amphotericin B had higher activity against planktonic cells; however, resveratrol and Regrapex-R-forte showed anti-biofilm effects, both in inhibition of biofilm formation and in the eradication of mature biofilm. The minimum biofilm eradicating concentration (MBEC80) for Regrapex-R-forte was found to be 2222 mg/L (in which resveratrol concentration is 200 mg/L). These methods demonstrated that Regrapex-R-forte can be employed as an anti-biofilm agent, as it has similar effect as amphotericin B (MBEC80 = 700 mg/L), which is routinely used in clinical practice.

Subcutaneous Infection Associated with Trichosporon ovoides: A Case Report and Review of Literature.

Trichosporon species are opportunistic yeasts which can cause infections, especially in immunocompromised patients. This is a report of Trichosporon ovoides that caused subcutaneous infection in a patient with underlying ischemic heart disease. The identification of fungal isolate was confirmed by PCR sequencing of ITS and large subunit regions in rRNA gene. In vitro susceptibility study showed that the isolate was susceptible to amphotericin B, fluconazole and voriconazole, and resistant to caspofungin, anidulafungin and itraconazole. The lesion improved after treatment with oral fluconazole and topical miconazole.

Trichosporon inkin as an Emergent Pathogen in Patients With Severe Pemphigus.

IMPORTANCE: To our knowledge, these are the first reports of bloodstream infections by Trichosporon inkin in patients with pemphigus. OBSERVATIONS: Trichosporon inkin, a novel organism causing bloodstream infection, was detected in 2 patients with pemphigus. An elderly man with pemphigus foliaceus died despite treatment with liposomal amphotericin B, 3 mg/kg/d, and a young girl with pemphigus vulgaris responded to treatment with voriconazole, 8 mg/kg/d, for 24 days. One of the T inkin isolates had a minimal inhibitory concentration of 2 mg/L against amphotericin B, suggesting resistance to the drug. CONCLUSIONS AND RELEVANCE: Delayed suspicion of invasive infection by T inkin may result in a poor outcome in patients with severe forms of pemphigus. This opportunistic infection is highly refractory to conventional potent antifungal treatment.

Trichosporon asahii infection presenting as chronic meningo-ventriculitis and intra ventricular fungal ball: a case report and literature review.

Central nervous system trichosporonosis is a rare clinical entity and so far only six cases including three each of brain abscess and meningitis has been on record. We report a rare case of chronic meningo-ventriculitis and intraventricular fungal ball due to Trichosporon asahii in an 18-year-old immunocompetent male from Burundi, east Africa. Neuroendoscopy showed multiple nodules and a fungal ball within the ventricle, which on culture grew T. asahii. He was initially empirically treated with liposomal amphotericin B. However, the antifungal susceptibility testing of T. asahii isolate revealed high minimum inhibitory concentration for amphotericin B (2 µg ml⁻¹), flucytosine (16 µg ml⁻¹) and caspofungin (2 µg ml⁻¹) but exhibited potent activity for voriconazole, posaconazole, itraconazole and fluconazole. The patient rapidly succumbed to cardiac arrest before antifungal therapy could be changed. Although disseminated trichosporonosis has been increasingly reported the diagnosis represents a challenge especially in rare clinical settings such as intraventricular fungal ball in the present case, which has not been described previously.

Prompt diagnosis and effective treatment of Trichosporon asahii catheter-related infection in non-immunocompromised neurosurgical patient.

Trichosporon asahii is a rare but emerging fungal pathogen that causes severe and life-threatening infections with high mortality rate, mostly in immunocompromised patients. It could be easily misdiagnosed due to lack of awareness, especially when invasive or deep-seated infections occur in non-immunocompromised patients, and inadequately treated since the clinical failures and high minimum inhibitory concentrations to some antifungal agents have been described. We present a case of T. asahii catheter-related infection in 66-year-old comatose patient with polytrauma, who was not immunodeficient, but was receiving broad-spectrum antibiotics for a long period. Due to prompt diagnosis and treatment which included catheter replacement and voriconazole, the patient successfully recovered from this infection. The aims of this case report were to highlight the importance of recognizing this otherwise colonizing yeast as potentially dangerous pathogen in non-immunocompromised patients with a long-term antibiotic therapy, and to emphasize the importance of the right therapeutic choice due to its resistance to certain antifungal agents.

Emerging Trichosporon asahii in elderly patients: epidemiological and molecular analysis by the DiversiLab system.

Trichosporon asahii has been recognized as an emerging opportunistic agent for invasive infections, mainly in immunocompromised patients. Urinary tract infections by this pathogen may also occur, especially in patients with urinary obstruction or those undergoing vesical catheterization and antibiotic treatment. Many outbreaks of Trichosporon spp. have been detected after urinary catheter manipulations. We report the molecular-epidemiological characterization of T. asahii in our institution using the DiversiLab system for the molecular strain typing and compare three different methods for susceptibility testing. Our results present T. asahii as an emergent pathogen in elderly patients with urinary drainage devices that can be adequately treated with triazoles, with voriconazole being the most active. Broth dilution and Vitek 2 had good concordance, while Etest showed more discrepancies. In addition, the DiversiLab system for clonal strain typing may be a useful tool for fast and accurate management of nosocomial outbreaks.

Screening of some essential oils against Trichosporon species.

White Piedra is a superficial mycoses characterized by nodules on the hair shaft, caused by the basidiomycetous yeast Trichosporon species. In this study 25 essential oils were extracted and screened against two Trichosporon species i.e. Trichosporon asahii and Trichosporon cutaneum. Both these fungi procured from MTCC Chandigarh were maintained on yeast malt agar plates and tubes at 25 degrees C. Two screening methods viz., agar well diffusion assay and minimum inhibitory concentration were adopted for the study. The results showed that the maximum anti-yeast activity against T. asahii and T. cutaneum was demonstrated by oil of Mentha piperita showing full inhibition of both the fungi, Melaleuca alternifolia with an inhibition zone of 45 and 40 mm, Cymbopogon winterians with inhibition zone of 45 and 45 mm and Cymbopogon flexuosus with 35 and 30 mm inhibition zones. The oil of Trachyspermum ammi exhibited 10 and 20 mm, Abelmoschus moschatus exhibited 30 and 20 mm, Salvia sclarea showed 20 and 18 mm and Jasminum officinale exhibited 25 and 15 mm inhibition zones showing moderate activity. The oil of Cyperus scariosus, Pogostemon patchouli and Rosa damascene showed no inhibition zone against both the fungi while Vetiveria zizanoides exhibited no inhibition in case of T. asahii and inhibition zone of 10 mm in case of T. cutaneum demonstrating comparatively low activity against both the fungi. These results support that the essential oils can be used to cure superficial mycoses and these oils may have significant role as pharmaceuticals and preservatives.

Potential utilization of waste sweetpotato vines hydrolysate as a new source for single cell oils production by Trichosporon fermentans.

The enzymatic hydrolysate of sweetpotato vines (SVH) characterized as an effective nutrients supplier with low nitrogen availability was firstly used as a substrate by Trichosporon fermentans for single cell oils (SCOs) production. Batch-fermentation experiments on various SVH based media suggested that co-fermentation of SVH and some high-sugar content substrates would be much more efficient and less-cost for SCOs production. A lipid yield of 9.6 g l(-1) with a lipid content of 35.6% was achieved on the SVH without any addition, while 27.6 and 17.7 g l(-1) lipid were respectively obtained on the fructose supplemented SVH media and the SVH mixed with acid treated wheat straw hydrolysate (WSH). The positive effect of SVH on the lipid production of T. fermentans was further demonstrated with a kinetic investigation revealing that SVH had a remarkable promoting effect on the biomass formation and the substrate uptake.

Antifungal activity of the honeybee products against Candida spp. and Trichosporon spp.

Honeybee products (honey, royal jelly, pollen, and propolis) were evaluated for their ability to inhibit the growth of 40 yeast strains of Candida albicans, Candida glabrata, Candida krusei, and Trichosporon spp. The broth microdilution method was used to assess the antifungal activity of honeybee products against yeasts. Fluconazole was selected as the antifungal control agent. Using the broth microdilution method, minimal inhibitory concentration ranges with regard to all isolates were 5-80% (vol/vol), 0.06-1 µg/mL, 0.002-0.25 µg/mL, 0.006-0.1 µg/mL, and 0.02-96 µg/mL for honey, royal jelly, pollen, propolis, and fluconazole, respectively. The antifungal activities of each product decreased in the following order: propolis >pollen > royal jelly > > honey. This study demonstrated that honeybee products, particularly propolis and pollen, can help to control some fluconazole-resistant fungal strains.

[Micafungin: experimental therapy of fungal infections in animal models]. / Micafungina en el tratamiento de la infección fúngica en modelos animales.

BACKGROUND: Micafungin is an echinocandin antifungal drug recently approved for the treatment of candidiasis. The possibility of its clinical use against other invasive mycoses, has aroused the interest of numerous investigators in evaluating its efficacy in different animal models. OBJECTIVES: To critically review the current data on the use of micafungin in the treatment of invasive mycoses in animal models. METHODS: We searched the PubMed/Medline data base (National Library of Medicine) from 2005 to 2008, both inclusive, on the use of micafungin in the experimental treatment of the fungal infection. RESULTS AND CONCLUSIONS: Seven, of a total of 18 articles reviewed, were done in animal models of candidiasis and six in animal models of pulmonary or SNC aspergillosis. Similarly to the other echinocandins, caspofungin and anidulafungin, micafungin seems to exert a fungicidal activity against Candida albicans and Candida glabrata and a fungistatic activity against Aspergillus fumigatus. The paradoxical effect observed in lung tissue the experimental caspofungin treatment of aspergillosis has not been seen in the case of micafungin. The available data demonstrate a higher efficacy of micafungin versus fluconazole in the experimental treatment of C. albicans infections caused by strains susceptible in vitro to both drugs. To improve the efficacy of micafungin in the treatment of C. glabrata and A. fumigatus infections, several authors have tested different combined therapies, the combination of micafungin with amphotericin B being that showed the best results.

Antimicrobial activity of some medicinal plants of the Cerrado, Brazil.

In order to determine the potential of Cerrado plants as sources of antimicrobial activity, the phytochemical screening of ethanol extracts from Virola surinamensis, Qualea grandiflora, Alchornea castaneifolia, Hancornia speciosa and Curatella americana traditionally used in folk medicine are reported.

Breakthrough Trichosporon asahii fungemia in neutropenic patient with acute leukemia while receiving caspofungin.

A 47-year-old man with newly diagnosed acute myeloblastic leukemia and non-insulin-dependent diabetes mellitus developed Trichosporon asahii fungemia while receiving caspofungin as empirical antifungal therapy. The diagnosis was based on repeated isolation of T. asahii in culture of blood for three times. Despite treatment with amphotericin B and voriconazole, the patient died. The in vitro antifungal susceptibilities of the T. asahii isolates were only available after the patient died. In vitro antifungal susceptibility tests showed high caspofungin and amphotericin B minimal inhibitory concentrations (MICs) value for this Trichosporon strain (MICs, 16 microg/ml, and>32 microg/ml, respectively). Fluconazole, itraconazole, and voriconazole exhibited low MICs in vitro (MICs, 4 microg/ml, 0.5 microg/ml, and

Combined therapies in a murine model of blastoschizomycosis.

In a murine model of blastoschizomycosis, amphotericin B combined with micafungin, flucytosine or voriconazole did not improve the efficacy of fluconazole. However, such combinations can constitute therapeutic options for those cases where fluconazole fails.

The prophylactic effectiveness of various antifungal agents against the progression of trichosporonosis fungemia to disseminated disease in a neutropenic mouse model.

Neutropenic mice with latent trichosporonemia were given various antifungal agents (amphotericin B, fluconazole, itraconazole) or saline to determine which antifungal agent could be useful for prophylaxis. The 3-week-survival rate was 80% in the fluconazole group, 50% in the amphotericin B group, 45% in the itraconazole group, and 30% in the saline group. Compared with the other antifungal agents, fluconazole offered superior prophylaxis against the progression of trichosporonosis fungemia to disseminated disease (P<0.05). These results suggest that clinical studies are warranted to investigate fluconazole prophylaxis of trichosporonosis progression in neutropenic patients, such as people receiving chemotherapy and patients who have received solid organ transplants.

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.

Trichosporon asahii fungemia in a patient with non-hematological malignancy.

Trichosporon fungemia is usually seen in neutropenic patients with underlying hematological malignancies. In this report we describe a fatal case of Trichosporon asahii fungemia in a non-neutropenic patient with a non-hematological malignancy. For 1 week the patient exhibited hematuria, weakness, easy fatigability and headaches. At admission she had anemia, renal failure and evidence of right hydronephrosis and bladder wall masses as detected by CT scan. She did not have a history of tobacco abuse, contact with urinary carcinogens or Schistosoma infestation; her clinical picture was suggestive of bladder cancer. After some investigations the patient underwent radical cystectomy and ileal conduit surgery because of transitional cell carcinoma in the urinary bladder. After an initial uneventful improvement postoperatively the patient deteriorated and died of septic shock despite all reanimation efforts and antibiotherapy including fluconazole. The blood culture obtained 4 days before the patient died revealed T. asahii, which was isolated on the day she died and found to be resistant to fluconazole and caspofungin. This report suggests that clinicians remain aware that T. asahii fungemia may develop in clinically deteriorated patients even if they do not have a hematological malignancy.

What defines the quality of patient care in tinea pedis?

OBJECTIVES: The aim of this study has been to evaluate patients with tinea pedis for their demographic data and attitudes affecting the treatment of disease, and to compare the in vitro activity of 10 antifungal agents and to relate them to their in vivo activity. METHODS: Patients with positive mycological examination were enrolled in the study, and a questionnaire comprised of 22 questions was administered. A mycological culture was carried out for each specimen. The antifungal susceptibility of the subcultured species was determined for griseofulvin, terbinafine, ciclopiroxolamine, fluconazole, ketoconazole, itraconazole, bifonazole, sulconazole, oxiconazole and miconazole with microdilution. RESULTS: Mycological cultures were carried out from 59 patients and there were 35 positive cultures (59.3%). The dermatophytes were Trichophyton rubrum (n = 25) and Trichophyton mentagrophytes (n = 3). The yeasts were Candida albicans (n = 7), Candida glabrata (n = 1) and Trichosporon (n = 2). In the minimum inhibitory concentration (MIC) study, the mean +/- standard error of the mean (SEM) MICs of the antifungals for T. rubrum were as follows: terbinafine 0.01 +/- 0.003, oxiconazole 0.16 +/- 0.05, sulkonazole 0.31 +/- 0.05, miconazole 0.45 +/- 0.15, itraconazole 0.74 +/- 0.01, ketokonazole 1.03 +/- 0.17, ciclopiroxolamine 1.30 +/- 0.12, bifonazole 1.94 +/- 0.51, griseofulvin 4.87 +/- 0.61, and fluconazole 17.91 +/- 3.67 microg/mL. CONCLUSION: Our study supports that azoles could be used as first-line treatment, as oxiconazole is very effective for both dermatophytes and C. albicans. Correlation between in vitro results and clinical outcomes of cases of dermatophytes is still to be established and interpretive breakpoints defined, in order to increase the quality of patient care in tinea pedis.