Treatment of chytridiomycosis with reduced-dose itraconazole

Jones, Megan E. B.; Paddock, David A.; Bender, Lee; Allen, Jack L.; Schrenzel, Mark D.; Pessier, Allan P.

doi:10.3354/dao02475

Cited by 36 publications

(24 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This same concentration was trialed on recent metamorphs and found to be unsuccessful at treating infection 15 . Because there is risk of negative side effects with itraconazole treatment, some practitioners have used one half the usual concentration (0.005%) for 11 consecutive days and found this to be successful in curing Bd infections 16 .…”

Section: Introductionmentioning

confidence: 99%

Reduced Itraconazole Concentration and Durations Are Successful in Treating <em>Batrachochytrium dendrobatidis</em> Infection in Amphibians

Brannelly

2014

JoVE

View full text Add to dashboard Cite

Amphibians are experiencing the greatest decline of any vertebrate class and a leading cause of these declines is a fungal pathogen, Batrachochytrium dendrobatidis (Bd), which causes the disease chytridiomycosis. Captive assurance colonies are important worldwide for threatened amphibian species and may be the only lifeline for those in critical threat of extinction. Maintaining disease free colonies is a priority of captive managers, yet safe and effective treatments for all species and across life stages have not been identified. The most widely used chemotherapeutic treatment is itraconazole, although the dosage commonly used can be harmful to some individuals and species. We performed a clinical treatment trial to assess whether a lower and safer but effective dose of itraconazole could be found to cure Bd infections. We found that by reducing the treatment concentration from 0.01-0.0025% and reducing the treatment duration from 11-6 days of 5 min baths, frogs could be cured of Bd infection with fewer side effects and less treatment-associated mortality. Video LinkThe video component of this article can be found at

show abstract

Section: Introductionmentioning

confidence: 99%

Reduced Itraconazole Concentration and Durations Are Successful in Treating <em>Batrachochytrium dendrobatidis</em> Infection in Amphibians

Brannelly

2014

JoVE

View full text Add to dashboard Cite

show abstract

“…This treatment can lead to depigmentation in tadpoles (25) and toxic effects in some adult amphibians (26), although recent studies have suggested that a reduced dose and treatment length may still be effective (27,28). Although some toxicity was noted in these studies, this may have been a result of life stage (27) or death from advanced chytridiomycosis before treatment could have an effect (28). There is also a growing trend of itraconazole resistance in other fungal pathogens, including species of Aspergillus (29,30) and Candida (31)(32)(33), indicating that B. dendrobatidis resistance to itraconazole could become a concern in the future.…”

mentioning

confidence: 99%

“…Specifically, the treatment involves exposing frogs to a 0.01% (100 g/ml) itraconazole (Sporanox) bath for 10 min daily for 10 days (24). This treatment can lead to depigmentation in tadpoles (25) and toxic effects in some adult amphibians (26), although recent studies have suggested that a reduced dose and treatment length may still be effective (27,28). Although some toxicity was noted in these studies, this may have been a result of life stage (27) or death from advanced chytridiomycosis before treatment could have an effect (28).…”

mentioning

confidence: 99%

Evaluation of Amphotericin B and Chloramphenicol as Alternative Drugs for Treatment of Chytridiomycosis and Their Impacts on Innate Skin Defenses

Holden

Ebert

Canning

et al. 2014

Appl Environ Microbiol

View full text Add to dashboard Cite

c Chytridiomycosis, an amphibian skin disease caused by the emerging fungal pathogen Batrachochytrium dendrobatidis, has been implicated in catastrophic global amphibian declines. The result is an alarming decrease in amphibian diversity that is a great concern for the scientific community. Clinical trials testing potential antifungal drugs are needed to identify alternative treatments for amphibians infected with this pathogen. In this study, we quantified the MICs of chloramphenicol (800 g/ml), amphotericin B (0.8 to 1.6 g/ml), and itraconazole (Sporanox) (20 ng/ml) against B. dendrobatidis. Both chloramphenicol and amphotericin B significantly reduced B. dendrobatidis infection in naturally infected southern leopard frogs (Rana [Lithobates] sphenocephala), although neither drug was capable of complete fungal clearance. Long-term exposure of R. sphenocephala to these drugs did not inhibit antimicrobial peptide (AMP) synthesis, indicating that neither drug is detrimental to this important innate skin defense. However, we observed that chloramphenicol, but not amphotericin B or itraconazole, inhibited the growth of multiple R. sphenocephala skin bacterial isolates in vitro at concentrations below the MIC against B. dendrobatidis. These results indicate that treatment with chloramphenicol might dramatically alter the protective natural skin microbiome when used as an antifungal agent. This study represents the first examination of the effects of alternative antifungal drug treatments on amphibian innate skin defenses, a crucial step to validating these treatments for practical applications.

show abstract

“…However, this concentration may be much higher than what is necessary to cure Bd infection as lower doses have also been successful in some cases (Garner et al 2009b, Pessier & Mendelson 2010, Jones et al 2012). Because of the potential for side effects, treatment in a 0.01% itraconazole solution is not recommended for all amphibian species and life stages (Garner et al 2009b, Pessier & Mendelson 2010.…”

Section: Treatment Of Chytridiomycosismentioning

confidence: 99%

“…L. caerulea has been treated clinically in previous studies using fluconazole, benzalkonium chloride (Berger et al 2009), chloramphenicol (Young et al 2012) and 0.01% itraconazole (Jones et al 2012). L. caerulea is a hylid treefrog that is widely distributed in Australia.…”

Section: Study Speciesmentioning

confidence: 99%

Clinical trials with itraconazole as a treatment for chytrid fungal infections in amphibians

Brannelly¹,

Richards‐Zawacki²,

Pessier³

2012

Dis. Aquat. Org.

Self Cite

View full text Add to dashboard Cite

Due in large part to recent global declines and extinctions, amphibians are the most threatened vertebrate group. Captive assurance colonies may be the only lifeline for some rapidly disappearing species. Maintaining these colonies free of disease represents a challenge to effective amphibian conservation. The fungal disease chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), is one of the major contributors to global amphibian declines and also poses a serious threat to captive assurance colonies. Many treatment options for Bd infection have not been experimentally tested and the commonly administered dosages of some drugs are known to have negative side effects, highlighting a need for clinical trials. The objective of this study was to clinically test the drug itraconazole as a method for curing Bd infection. We bathed Bd-positive juveniles of 2 anuran amphibian species, Litoria caerulea and Incilius nebulifer, in aqueous itraconazole, varying the concentration and duration of treatment, to find the combination that caused the fewest side effects while also reliably ridding animals of Bd. Our results suggest that a bath in 0.0025% itraconazole for 5 min d −1 for 6 d reliably cures Bd infection and causes fewer side effects than the longer treatment times and higher concentrations of this drug that are commonly administered.

show abstract

Treatment of chytridiomycosis with reduced-dose itraconazole

Cited by 36 publications

References 19 publications

Reduced Itraconazole Concentration and Durations Are Successful in Treating <em>Batrachochytrium dendrobatidis</em> Infection in Amphibians

Reduced Itraconazole Concentration and Durations Are Successful in Treating <em>Batrachochytrium dendrobatidis</em> Infection in Amphibians

Evaluation of Amphotericin B and Chloramphenicol as Alternative Drugs for Treatment of Chytridiomycosis and Their Impacts on Innate Skin Defenses

Clinical trials with itraconazole as a treatment for chytrid fungal infections in amphibians

Contact Info

Product

Resources

About