title: Multicentre Etest evaluation of in vitro activity of conventional antifungal drugs against European bovine mastitis Prototheca spp. isolates.
abstract: OBJECTIVE
  Bovine mammary protothecosis is a serious pathology that entails high economic losses in the dairy industry. The disease, the frequency of which has recently been increasing worldwide, is caused by unicellular, achlorophyllous, yeast-like algae of two species: Prototheca zopfii and Prototheca blaschkeae. The objective of this study was to investigate the in vitro activity of a panel of conventional antifungal drugs against Prototheca spp. isolates.
  
  
  METHODS
  A total of 144 P. zopfii genotype 2 and P. blaschkeae strains isolated from milk of mastitic cows were subjected to drug susceptibility testing by Etest methodology.
  
  
  RESULTS
  Five out of ten antifungal drugs tested exhibited no activity against Prototheca spp. isolates. The best activity against Prototheca spp. was demonstrated by amphotericin B (MIC₉₀ of 1.5 mg/L). The MICs differed significantly (P < 0.01) between P. zopfii genotype 2 and P. blaschkeae, with the latter species being more susceptible to amphotericin B and azoles. Marked differences (P < 0.05) in azole and amphotericin B activities were noted among Prototheca spp. isolates originating from different European countries. Based on the correlation coefficients, a considerable cross-interaction was found among MICs of azoles and between MICs of azoles and amphotericin B for Prototheca spp. (P < 0.03).
  
  
  CONCLUSIONS
  This study represents the largest, cross-European evaluation of antifungal activity against Prototheca spp. to date. The activity of amphotericin B against Prototheca spp. validates its potential use as a therapeutic agent against bovine protothecosis. For laboratory testing of drug activity against Prototheca spp., the Etest method is encouraged, due to its technical simplicity, rapidity and high intra- and inter-laboratory reproducibility.
authors.affiliation: Department of Applied Microbiology, Institute of Microbiology, Faculty of Biology, University of Warsaw, Warsaw, Poland. t.jagielski@biol.uw.edu.pl
authors.forename: Tomasz
authors.initials: T
authors.lastname: Jagielski
authors.forename: Pietro
authors.initials: P
authors.lastname: Buzzini
authors.forename: Henryka
authors.initials: H
authors.lastname: Lassa
authors.forename: Edward
authors.initials: E
authors.lastname: Malinowski
authors.forename: Eva
authors.initials: E
authors.lastname: Branda
authors.forename: Benedetta
authors.initials: B
authors.lastname: Turchetti
authors.forename: Angela
authors.initials: A
authors.lastname: Polleichtner
authors.forename: Uwe
authors.initials: U
authors.lastname: Roesler
authors.forename: Paul-Emile
authors.initials: PE
authors.lastname: Lagneau
authors.forename: Sara
authors.initials: S
authors.lastname: Marques
authors.forename: Eliane
authors.initials: E
authors.lastname: Silva
authors.forename: Gertrude
authors.initials: G
authors.lastname: Thompson
authors.forename: Radosław
authors.initials: R
authors.lastname: Stachowiak
authors.forename: Jacek
authors.initials: J
authors.lastname: Bielecki
mesh_terms: D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology*; D002417:Cattle; D005260:Female; D008414:Mastitis, Bovine / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D011525:Prototheca / Q000187:drug effects* / Q000302:isolation & purification*
chemical_list: D000935:Antifungal Agents