In December 2017 the new revised guideline for the management of invasive mycoses was published in the Netherlands.
Important change in the guideline is the management of invasive aspergillosis. The guideline now recommends combination antifungal therapy as first line treatment of patients suspected of invasive aspergillosis. The combination of voriconazole or isavuconazole with an echinocandin or with liposomal amphotericin B is recommended at least until results of resistance testing are obtained. The change was prompted by the high azole resistance rates in Aspergillus fumigatus that have been reported in the Netherlands, which range between 10% and 20% (Nethmap 2017). Only patients in whom results of resistance testing are expected rapidly, through direct resistance PCR, may be started on azole monotherapy. If azole susceptible infection is documented treatment can be changed to azole monotherapy.
The need to confirm the diagnosis and to test for resistance is also emphasized in the guideline. Maximal efforts should be undertaken to obtain samples for mycology culture and susceptibility testing. In A. fumigatus culture positive patients 4-well screening agar followed by MIC testing are mentioned as options to obtain information about resistance rapidly.