title: CLSI broth microdilution method for testing susceptibility of Malassezia pachydermatis to thiabendazole.
abstract: Thiabendazole, classified as antiparasitic and also used as an antifungal drug, can be found as otological solution indicated for treatment of parasitic and fungal external otitis in small animals. Malassezia pachydermatis is a yeast recognized as a normal inhabitant on the skin and mucous membranes of dogs and cats. However, it is considered an opportunistic agent that causes external otitis and dermatitis in these animals. The aim of this study was to evaluate the in vitro effect of thiabendazole against 51 isolates of M. pachydermatis using the CLSI Broth Microdilution method that has been adapted for this yeast species (NCCLS, 2002). Based on this test, the Minimum Inhibitory Concentrations (MIC) of thiabendazol was calculated. Subsequently, the susceptibility of each isolate against this antifungal was determined. It was observed that the MIC of thiabendazole against M. pachydermatis ranged from 0.03 to > 4 µg/mL. A total of 13.7% of the isolates were found to be resistant, 47.1% were intermediate and 39.2% were sensitive to the drug. The rate of resistance of the yeasts against thiabendazole was similar to the results previously obtained with other antifungals, while the adapted broth microdilution technique used in this study proved to be efficient.
authors.affiliation: Programa de Pós Graduação em Ciências Veterinárias, Universidade Federal do Rio Grande do Sul , Porto Alegre, RS , Brasil.
authors.forename: Patrícia da Silva
authors.initials: Pda S
authors.lastname: Nascente
authors.forename: Ana Raquel Mano
authors.initials: AR
authors.lastname: Meinerz
authors.forename: Renata Osório
authors.initials: RO
authors.lastname: de Faria
authors.forename: Luiz Filipe Damé
authors.initials: LF
authors.lastname: Schuch
authors.forename: Mário Carlos Araújo
authors.initials: MC
authors.lastname: Meireles
authors.forename: João Roberto Braga
authors.initials: JR
authors.lastname: de Mello
keywords: Malassezia pachydermatis; Minimum Inhibitory Concentration; thiabendazole
references.citation: J Feline Med Surg. 2005 Jun;7(3):141-5
references.pmid: 15922220
references.citation: Vet Clin North Am Small Anim Pract. 1990 Nov;20(6):1603-13
references.pmid: 2251742
references.citation: Antonie Van Leeuwenhoek. 1996 May;69(4):337-55
references.pmid: 8836432
references.citation: Res Vet Sci. 2000 Jun;68(3):291-3
references.pmid: 10877978
references.citation: Drugs Exp Clin Res. 1985;11(6):393-5
references.pmid: 3836136
references.citation: Antimicrob Agents Chemother. 2003 Jul;47(7):2342-4
references.pmid: 12821494
references.citation: J Vet Pharmacol Ther. 2003 Feb;26(1):5-29
references.pmid: 12603774
references.citation: Med Mycol. 2002 Apr;40(2):115-21
references.pmid: 12058723
references.citation: Vet Microbiol. 2007 May 16;122(1-2):172-7
references.pmid: 17257784
references.citation: J Clin Microbiol. 2004 Aug;42(8):3589-93
references.pmid: 15297502
references.citation: J Am Vet Med Assoc. 1992 Sep 15;201(6):879-82
references.pmid: 1399796
references.citation: J Vet Diagn Invest. 2005 Jul;17(4):316-22
references.pmid: 16130988
references.citation: Med Mycol. 2006 Mar;44(2):175-84
references.pmid: 16519021
references.citation: J Small Anim Pract. 1995 Apr;36(4):147-50
references.pmid: 7603055
references.citation: Nihon Juigaku Zasshi. 1990 Aug;52(4):851-3
references.pmid: 2391785
references.citation: Vet Dermatol. 2002 Jun;13(3):141-50
references.pmid: 12074703
references.citation: Clin Microbiol Rev. 2001 Oct;14(4):643-58, table of contents
references.pmid: 11585779
references.citation: Med Mycol. 1999 Oct;37(5):295-306
references.pmid: 10520154
references.citation: Med Mycol. 2007 Jun;45(4):287-303
references.pmid: 17510854