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Non-Candida opportunistic yeasts are emerging causes of bloodstream infection (BSI) in immunocompromised hosts. However, their clinical presentation, management, and outcomes in stem cell transplant (SCT) recipients are not well described. We report the first case to our knowledge of Pseudozyma BSI in a SCT recipient. He had evidence of cutaneous involvement, which has not been previously described in the literature. He became infected while neutropenic and receiving empiric micafungin, which is notable because Pseudozyma is reported to be resistant to echinocandins. He was successfully treated with the sequential use of liposomal amphotericin B and voriconazole. A review of the literature revealed nine reported instances of Pseudozyma fungemia. We performed a retrospective review of 3557 SCT recipients at our institution from January 2000 to June 2015 and identified four additional cases of non-Candida yeast BSIs. These include two with Cryptococcus, one with Trichosporon, and one with Saccharomyces. Pseudozyma and other non-Candida yeasts are emerging pathogens that can cause severe and disseminated infections in SCT recipients and other immunocompromised hosts. Clinicians should have a high degree of suspicion for echinocandin-resistant yeasts, if patients develop breakthrough yeast BSIs while receiving echinocandin therapy., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

This study aims to evaluate the effect of efflux pump modulators (EPMs) on the minimal inhibitory concentration (MIC) of fluconazole (FLZ) and voriconazole (VOR) in Malassezia furfur and Malassezia pachydermatis. The in vitro efficacy of azoles, in combination with EPMs (ie haloperidol-HAL, promethazine-PTZ and cyclosporine A-CYS), against 21 M. furfur from bloodstream infection patients and 14 M. pachydermatis from the skin of dogs with dermatitis, was assessed using a broth microdilution chequerboard analysis. Data were analysed using the model-fractional inhibitory concentration index (FICI) method. The MIC of FLZ and VOR of Malassezia spp. decreased in the presence of sub-inhibitory concentrations of HAL and/or PTZ. The synergic effect was observed only in strains with FLZ MIC≥128 μg/mL for M. furfur, FLZ MIC≥64 μg/mL for M. pachydermatis and VOR MIC≥4 μg/mL in both Malassezia spp. These results suggest that the drug efflux pumps are involved as defence mechanisms to azole drugs in Malassezia yeast. The synergism might be related to an increased expression of efflux pump genes, eventually resulting in azole resistance phenomena. Finally, the above FLZ and VOR MIC values might be considered the cut-off to discriminate susceptible and resistant strains., (© 2016 Blackwell Verlag GmbH.)

OBJECTIVE To determine the pharmacokinetics of terbinafine in little brown myotis (Myotis lucifugus) infected with Pseudogymnoascus destructans. ANIMALS 123 bats from a P destructans-infected hibernation site in Virginia. PROCEDURES 3 bats were euthanized and necropsied to confirm the presence of P destructans within the population. The remaining 120 bats were systematically assigned to 6 groups (20 bats/group). Bats in each of 3 groups received 6, 20, or 60 mg of terbinafine/kg, SC, once daily for 10 days. Bats in another group received 200 mg of terbinafine/kg, SC, once daily for 5 days. Bats in 1 group received the terbinafine vehicle solution (0.1 mL/kg, SC, once daily for 10 days). Bats in the remaining group did not receive any treatment. Following the treatment period (days 1 through 10), bats were housed in a hibernation chamber and monitored daily until euthanasia on day 42, 75, or 109. Tissue specimens were collected from all bats as soon as possible after death or euthanasia to determine terbinafine concentration. Within each group and tissue type, terbinafine concentration data were pooled, and pharmacokinetic parameters were calculated by noncompartmental methods. RESULTS Adverse neurologic effects and a high mortality rate before day 10 were observed in bats that received the highest terbinafine dose (200 mg/kg) but not those that received lower doses. Presumed therapeutic terbinafine concentrations (≥ 2 μg/g) were maintained in skin and wing for at least 30 and 6 days in bats that received the 60 and 20 mg/kg doses, respectively, but were not achieved in most bats that received the 6 mg/kg dose. Tissue terminal half-life ranged from 14 to 22 days. Terbinafine concentration in hair was positively correlated with that in skin and wing. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated terbinafine doses > 6 but < 200 mg/kg should be further evaluated for the treatment of P destructans-infected bats. Collection of serial hair specimens may represent a noninvasive method for monitoring terbinafine concentration in treated bats.

A case of disseminated infection with Fusarium oxysporum following chemotherapy of acute myelogenous leukemia is reported. Antifungal treatment was successful with a 13-day course of oral terbinafine 250 mg t.i.d. in combination with amphotericin B deoxycholate 1.0-1.5 mg/kg qd and subsequently intravenous liposomal amphotericin B 5 mg/kg qd. Preceding monotherapy with amphotericin B deoxycholate 1.0-1.5 mg/kg qd had not stopped the progression of infection. The combination therapy described here represents a novel approach to the treatment of Fusarium spp. in the immunocompromised host in whom Fusarium spp. are known to cause disseminated infection with high mortality.

Griseofulvin is a metabolic product of Penicillium spp. It was the first available oral agent for the treatment of dermatophytoses and has now been used for more than forty years. Griseofulvin is fongistatic, the exact mechanism in witch it inhibits the growth of dermatophytes is doubtful. Several ways are invoked: inhibition of fungal cell mitosis and nuclear acid synthesis, probable interference with the function of microtubules. Griseofulvin is poorly absorbed from the gastrointestinal tract. Absorption is enhanced by administration with fatty meal. Peak plasma occurs four hours after oral administration. Griseofulvin is detected in the outer layer of the stratum corneum soon after it is ingested, it is diffused from the extracellular fluid and sweat. There is no information regarding the mechanism by witch the drug is delivered to nails and hair. Deposition in the newly formed cells could be the major factor. Griseofulvin has also anti-inflammatory properties and some direct vasodilatory effects when it is used in high doses. It is metabolised by the liver microsomial enzyme system and excreted in the urine. The half-life is 9 to 21 hours. Griseofulvine has been used in the therapy of dermatophyte onychomycosis, treatment periods from 6 to 18 months were necessary with disappointing results and numerous relapses. Newer oral antifungal agents are now preferred especially in toenail infections. For many authors griseofulvin is still the treatment of choice of tinea capitis. Doses are 15-20 mg/kg/d for 6 to 8 weeks in children with the microsized form. Clinical response rates have been reported between 80 and 90 p. 100 in controlled studies. Griseofulvin is well-tolerated particulary in children. More frequent side effects are minor: headaches, gastrointestinal reactions and cutaneous eruptions. The major drug interactions has been noted with phenobarbital, anticoagulants and oral contraceptives.

Background: Two new systemic antifungal agents, terbinafine and itraconazole, have expanded the choices for treatment of onychomycosis. The pharmacokinetic and pharmacologic properties provide the basis of their activity and are related to their efficacy and safety in dermatophyte infections., Objective: We describe the pharmacodynamics, pharmacokinetics, and pharmacology of terbinafine and itraconazole and the features that form a framework for comparing their efficacy. PHARMACODYNAMICS: Both terbinafine and itraconazole ultimately block ergosterol synthesis; terbinafine disrupts fungal cell wall synthesis earlier (squalene to squalene epoxide) than does itraconazole (lanosterol to ergosterol). In vitro, terbinafine exposure results in a toxic accumulation of squalene and decreased production of ergosterol. Minimal inhibitory concentrations (MICs) of terbinafine for dermatophytes are essentially equal to minimal fungicidal concentrations (MFCs). However, the MFCs of itraconazole are much higher than the MICs. PHARMACOLOGIC PROFILE: Both itraconazole and terbinafine penetrate keratinizing tissue; levels reached in nail plate exceed those in plasma. Therapeutic levels of the itraconazole persist in nails for up to 6 months after discontinuation of 3 months of therapy (200 mg/day) and during various pulsed cycles. After discontinuation of 1 month of therapy, terbinafine persists at therapeutic levels in the nail. Itraconazole has an affinity for mammalian cytochrome P-450 enzymes as well as for fungal P-450-dependent enzyme, and thus has the potential for clinically important interactions (e.g., astemizole, terfenadine, rifampin, oral contraceptives, H2 receptor antagonists, warfarin, cyclosporine). Terbinafine is not metabolized through this system and has little potential for drug-drug interactions., Conclusion: The low MFCs exhibited by terbinafine for dermatophytes may be important in its clinical efficacy and low relapse rates. The safety profile of terbinafine directly reflects its mechanism of action.