Gert van der Hoek
In Memoriam - Editor, Senior Moderator
The use of antifungal agents in agriculture causes increasing resistance in hospitalized patients
Editorial , Journal Clinical Infectious Diseases
Voriconazole Resistance in Aspergillus fumigatus: Should We Be Concerned?
The triazole class of antifungal agents provides the backbone of human antifungal therapy. Resistance is therefore problematic.
The clinical impact depends on resistance frequency and which pathogens are affected. Triazole resistance in Aspergillus fumigatus was first described in 1997 (in isolates from California in 1989) and has increased in frequency over the last decade. Itraconazole resistance has now been described from most developed countries (including Canada, India, China, and the United States), and a large proportion of these isolates are cross-resistant to voriconazole and posaconazole [1].
To add to this evolving scenario, in this issue of Clinical Infectious Diseases, van der Linden and colleagues in Nijmegen, the Netherlands, have now described voriconazole resistance, often without accompanying itraconazole or posaconazole resistance, and a new explanatory mechanism (TR46/Y121F/T289A) [2].
The isolates were picked up using drug-containing agar for primary culture of clinical specimens from all over the Netherlands and from many different patient types. The Nijmegen group has been particularly interested in environmental spread of triazole-resistant A. fumigatus, and has previously documented widespread dissemination of another specific-resistance mechanism, TR34/L98H, which confers voriconazole and itraconazole resistance [3]. Isolates containing the new resistant mechanism have been isolated from patients' homes and backyards, at a lower frequency than the TR34/L98H-containing strains. In Nijmegen, the hospital pediatric department yielded both strains from the air. Among 140 resistant strains identified in the environment, 14 (10%) contained the new resistant mutation TR46/Y121F/T289A [2]. One such strain has been identified in neighboring Belgium, but not elsewhere, yet.
So what are the implications of these findings?
Read more: http://cid.oxfordjournals.org/content/57/4/521.full.html?etoc
thanks to Pieter Lomans
Editorial , Journal Clinical Infectious Diseases
Voriconazole Resistance in Aspergillus fumigatus: Should We Be Concerned?
The triazole class of antifungal agents provides the backbone of human antifungal therapy. Resistance is therefore problematic.
The clinical impact depends on resistance frequency and which pathogens are affected. Triazole resistance in Aspergillus fumigatus was first described in 1997 (in isolates from California in 1989) and has increased in frequency over the last decade. Itraconazole resistance has now been described from most developed countries (including Canada, India, China, and the United States), and a large proportion of these isolates are cross-resistant to voriconazole and posaconazole [1].
To add to this evolving scenario, in this issue of Clinical Infectious Diseases, van der Linden and colleagues in Nijmegen, the Netherlands, have now described voriconazole resistance, often without accompanying itraconazole or posaconazole resistance, and a new explanatory mechanism (TR46/Y121F/T289A) [2].
The isolates were picked up using drug-containing agar for primary culture of clinical specimens from all over the Netherlands and from many different patient types. The Nijmegen group has been particularly interested in environmental spread of triazole-resistant A. fumigatus, and has previously documented widespread dissemination of another specific-resistance mechanism, TR34/L98H, which confers voriconazole and itraconazole resistance [3]. Isolates containing the new resistant mechanism have been isolated from patients' homes and backyards, at a lower frequency than the TR34/L98H-containing strains. In Nijmegen, the hospital pediatric department yielded both strains from the air. Among 140 resistant strains identified in the environment, 14 (10%) contained the new resistant mutation TR46/Y121F/T289A [2]. One such strain has been identified in neighboring Belgium, but not elsewhere, yet.
So what are the implications of these findings?
Read more: http://cid.oxfordjournals.org/content/57/4/521.full.html?etoc
Given the slim pipeline of new antifungal agents, complacency and inaction with respect to this topic is a poor option, given the history of antimicrobial resistance and the remarkable dispersal potential of A. fumigatus.
thanks to Pieter Lomans