Bone and joint infections by Mucorales, Scedosporium, Fusarium and even rarer fungi

Abstract

Mucorales, Scedosporium and Fusarium species are rarely considered as cause for bone and joint infections. However, these moulds are emerging as important fungal pathogens in immunocompromised and immunocompetent patients. Typical pre-disposing host conditions are immunosuppression and diabetes. Most common causative pathogens are Mucorales followed by Scedosporium and Fusarium. Acremonium and Phialemonium species are rare but some case reports exist. MRI is the gold standard imaging technique. Tissue specimens obtained as aspirates, imaging guided biopsy or open surgery need mycological and histopathological work-up for genus and species identification. Multimodal treatment strategies combine surgical debridement, drainage of joints or abscesses, removal of infected prosthetic joints and systemic antifungals. The treatment of mucormycosis is polyene based and may be combined with either posaconazole or – in rare cases – caspofungin. As Scedosporium species are intrinsically resistant to polyenes and azoles show absence of in vitro activity, voriconazole plus synergistic treatment regimens become the therapeutic standard. In fusariosis, fungal susceptibility is virtually impossible to predict, so that combination treatment of voriconazole and lipid-based amphotericin B should be the first-line strategy while susceptibility results are pending. In the absence of randomized controlled trials, infections due to the above moulds should be registered, e.g. in the registries of the European Confederation of Medical Mycology (ECMM).

• Acremonium species
• mucor
• osteomyelitis
• pseudallescheria
• rhizopus

Acknowledgements

We would like to thank Karen Pankraz for her support in revising the manuscript.

Declaration of interest

O.A.C. is supported by the German Federal Ministry of Research and Education (BMBF grant 01KN1106), has received research grants from 3 M, Actelion, Astellas, Basilea, Bayer, Celgene, Cubist, F2G, Genzyme, Gilead, GSK, Merck/MSD, Miltenyi, Optimer, Pfizer, Quintiles and Viropharma, is a consultant to 3 M, Astellas, Basilea, Cubist, F2G, Gilead, GSK, Merck/MSD, Optimer, Pfizer, Sanofi Pasteur and Summit/Vifor and received lecture honoraria from Astellas, Gilead, Merck/MSD and Pfizer. D.T. is affiliated to the COMBACTE consortium. She has received support from the Innovative Medicines Initiative Joint Undertaking under grant agreement no. 115523, resources of which are composed of financial contribution from the European Union's Seventh Framework Programme (FP7/2007–2013) and EFPIA companies’ in kind contribution. D.T. has received travel grants from MSD Sharp and Dohme and Gilead Sciences GmbH. P.K. has nothing to declare.