Actividad antifúngica in vitro de azoles y anfotericina B frente a Malassezia furfur por el método de microdilución M27-A3 del CLSI y Etest ®

Galvis-Marín, Juan Camilo; Rodriguez-Bocanegra, María Ximena; Pulido-Villamarín, Adriana; Castañeda-Salazar, Rubiela; Celis-Ramírez, Adriana Marcela; Linares-Linares, Melva Yomary

doi:10.1016/j.riam.2016.05.004

Cited by 10 publications

(17 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…To our knowledge, a limited number of studies have compared the E-test and CLSI BMD methods for in vitro antifungal susceptibility of M. furfur and only one reported concordance between the E-test and BMD [15]. On the contrary, the results from other studies also by considering M. pachydermatis emphasized the need for standardization of the tests by multicenter laboratory studies [27,31,32].…”

Section: Discussionmentioning

confidence: 99%

In Vitro Azole and Amphotericin B Susceptibilities of Malassezia furfur from Bloodstream Infections Using E-Test and CLSI Broth Microdilution Methods

et al. 2020

View full text Add to dashboard Cite

The number of reports of Malassezia furfur bloodstream infections is constantly increasing and there is a need for more simple antifungal susceptibility methods for their management. In this study, a total of 39 M. furfur isolates collected from hospitalized patients with fungemia were screened for antifungal susceptibility to azole and amphotericin B (AmB) using Clinical and Laboratory Standards Institute broth microdilution (CLSI BMD) and E-test in Sabouraud dextrose agar + 1% Tween80 (SDAt) and mDixon agar (DIX). Essential agreement (EA) and discrepancies between the two methods were evaluated after 48 h and 72 h reading times. Itraconazole (ITZ) and posaconazole (POS) displayed the lowest MIC values whereas fluconazole (FLZ) and AmB the highest, regardless of the methods and the reading time. The EA between BMD was >95% for FLZ and voriconazole (VOR) regardless of the media in the E-tests and reading time. The EA between BMD with E-test for AmB was >97% only when E-test in SDAt was used. The EA between BMD and E-test for ITZ and POS varied according to the media in E-test procedures and the reading time and was higher than 66.6% (POS) or 72% (ITZ) only when SABt was used. Substantial discrepancies for ITZ and POS were >5.1% regardless of the media and the reading time. This study suggests that the E-test in SABt represents an alternative method to CLSI BMD to evaluate the susceptibility of M. furfur to FLZ, VOR and AmB and not for ITZ and POS.

show abstract

Section: Discussionmentioning

confidence: 99%

In Vitro Azole and Amphotericin B Susceptibilities of Malassezia furfur from Bloodstream Infections Using E-Test and CLSI Broth Microdilution Methods

et al. 2020

View full text Add to dashboard Cite

show abstract

“…There were differences in the concentrations of L-lysine, amphotericin B (AB), and fluconazole (Flz) that inhibited growth of the Malassezia strains between the microdilution and agar well diffusion assays. This might be due to differences in lipidic composition of the broth and agar cultivation mediums, which influences the antifungal sensitivity 67,68 , despite of this, the agar well diffusion method has been shown suitable to evaluate the inhibition of natural extracts on M. furfur 69 and for both tests, L-lysine presented growth inhibition.…”

Section: Discussionmentioning

confidence: 99%

“…Broth microdilution methods were carried out according to the M27-A3 reference document of CLSI 97,98 . Inoculums were adjusted using Neubauer hemocytometer at 2 × 10 6 CFU/mL, the medium used was modified Sabouraud broth 67 and the concentrations employed (mg/mL) for L-lysine was from 1.5 to 4 and for L-threonine was from 16 to 25.…”

Section: Heterologous Expression Of Mphcs Mphsd and Mpsdh From M Pmentioning

confidence: 99%

New Therapeutic Candidates for the Treatment of Malassezia pachydermatis -Associated Infections

Sastoque

Triana

Ehemann

et al. 2020

Sci Rep

View full text Add to dashboard Cite

the opportunistic pathogen Malassezia pachydermatis causes bloodstream infections in preterm infants or individuals with immunodeficiency disorders and has been associated with a broad spectrum of diseases in animals such as seborrheic dermatitis, external otitis and fungemia. The current approaches to treat these infections are failing as a consequence of their adverse effects, changes in susceptibility and antifungal resistance. Thus, the identification of novel therapeutic targets against M. pachydermatis infections are highly relevant. Here, Gene Essentiality Analysis and Flux Variability Analysis was applied to a previously reported M. pachydermatis metabolic network to identify enzymes that, when absent, negatively affect biomass production. Three novel therapeutic targets (i.e., homoserine dehydrogenase (MpHSD), homocitrate synthase (MpHCS) and saccharopine dehydrogenase (MpSDH)) were identified that are absent in humans. Notably, L-lysine was shown to be an inhibitor of the enzymatic activity of MpHCS and MpSDH at concentrations of 1 mM and 75 mM, respectively, while L-threonine (1 mM) inhibited MpHSD. Interestingly, L-lysine was also shown to inhibit M. pachydermatis growth during in vitro assays with reference strains and canine isolates, while it had a negligible cytotoxic activity on HEKa cells. Together, our findings form the bases for the development of novel treatments against M. pachydermatis infections. The yeast M. pachydermatis is part of the skin microbiota of domestic and wild animals and behaves as an opportunistic pathogen causing external otitis and seborrheic dermatitis in dogs and cats. Particular conditions such as the presence of lipid-rich microenvironments, a local imbalance of the natural microbiota and altered immune states favor these infections 1. Dermatologic infections caused by M. pachydermatis often exhibit a chronic (recurrent) course and their treatment can be complicated due to the ability of this yeast to form biofilms 1. In addition, M. pachydermatis causes bloodstream infections in preterm infants or in individuals with immunodeficiency disorders. These infections are related to contamination of medical devices such as catheters, the transmission through medical staff and the administration of lipids through intravenous way 2,3. Recently, several factors contributing to M. pachydermatis virulence have been determined, which include the production of proteinases, phospholipases, hyaluronidases, and chondroitin-sulfatases 4. Currently, five classes of antifungal agents are used orally, topically or intravenously for the treatment of fungal infections. The first class is formed by the azoles (ketoconazole, itraconazole, clotrimazole, miconazole, and

show abstract

“…Aunque no existen recomendaciones de tratamiento basadas en la evidencia para infecciones invasivas por Malassezia spp., se han utilizado triazoles intravenosos o anfotericina B, mientras que flucitosina y las equinocandinas parecen ser inactivas 3 ; sin embargo, algunas publicaciones han documentado valores elevados de CIM para anfotericina B en las pruebas de susceptibilidad in vitro, como lo es el caso del trabajo de Velegraki et al que evaluó la sensibilidad de ocho especies de Malassezia frente a diferentes azoles y anfotericina B mediante microdilución y E-test, encontrando valores de CIM ≥ 16 ug/ml para anfotericina B en M. furfur, M. restricta, M. globosa y M. slooffiae 17 ; el estudio de Galvis et al que evaluó la actividad antifúngica in vitro de azoles y anfotericina B frente a 20 aislamientos clínicos de M. furfur por el método de microdilución y E-test, encontrando que el 70% de aislamientos fueron resistentes para anfotericina B por la técnica de referencia 16 ; y la revisión de Theleen et al que afirma que uno de los antifúngicos menos activos in vitro contra Malassezia spp. es anfotericina B, la cual mostró amplios rangos de CIM para M. furfur, M. sympodialis y M. globosa 1 , a pesar del éxito terapéutico observado en algunos reportes de caso al utilizar este antifúngico 6,7 .…”

Section: Discussionunclassified

“…Se realizó prueba de susceptibilidad antifúngica a este aislamiento por el método de difusión en agar (epsilométrico) de acuerdo al documento M44-A2 del Clinical and Laboratory Standards Institute (CLSI) 15 con algunas modificaciones para cumplir los requerimientos nutricionales del género Malassezia 16 , teniendo en cuenta que varias publicaciones comparando las técnicas de microdilución en caldo y E-test® han demostrado que este último es un método diagnóstico confiable para uso rutinario en los laboratorios de micología clínica 17,18 . Los antifúngicos utilizados fueron anfotericina B y voriconazol en una concentración de 0,002-32 ug/ml, y fluconazol 0,016-256 ug/ml.…”

Section: Descripción Del Casounclassified

Fungemia por Malassezia sympodialis en una Unidad de Cuidados Intensivos Neonatal de Colombia

Galvis-Marín

Giraldo-Ospina

Martínez-Ríos

et al. 2020

Infect

Self Cite

View full text Add to dashboard Cite

El género Malassezia comprende levaduras lipofílicas, comensales de la piel de humanos y animales, responsables de infecciones dermatológicas y sistémicas, particularmente en recién nacidos pretérmino hospitalizados en Unidades de Cuidados Intensivos Neonatal (UCIN) con catéteres venosos centrales, antibióticos de amplio espectro y nutrición parenteral rica en lípidos. La información acerca de las fungemias por este microorganismo es limitada, sin embargo, la mayoría de infecciones invasivas reportadas en la literatura han sido asociadas con M. furfur y M. pachydermatis. Se reporta un caso de fungemia por M. sympodialis en un recién nacido pretérmino hospitalizado en la UCIN de un hospital colombiano con sospecha clínica de sepsis neonatal, antibioticoterapia de amplio espectro y hemocultivos de rutina negativos. El aislamiento fue susceptible a fluconazol y voriconazol, y resistente a anfotericina B. Existen pocos reportes de fungemia producida por M. sympodialis, pero todos concuerdan en que es una levadura subestimada en individuos con factores predisponentes.

show abstract

Actividad antifúngica in vitro de azoles y anfotericina B frente a Malassezia furfur por el método de microdilución M27-A3 del CLSI y Etest ®

Cited by 10 publications

References 28 publications

In Vitro Azole and Amphotericin B Susceptibilities of Malassezia furfur from Bloodstream Infections Using E-Test and CLSI Broth Microdilution Methods

In Vitro Azole and Amphotericin B Susceptibilities of Malassezia furfur from Bloodstream Infections Using E-Test and CLSI Broth Microdilution Methods

New Therapeutic Candidates for the Treatment of Malassezia pachydermatis -Associated Infections

Fungemia por Malassezia sympodialis en una Unidad de Cuidados Intensivos Neonatal de Colombia

Contact Info

Product

Resources

About