Poster Presentation Australian Society for Microbiology Annual Scientific Meeting 2024

Hit for Saks(enaea): an emerging cause of severe mucormycosis in North Queensland (#13)

Sophie Cunningham 1 , Kae-Duen Su 2 , Nari Crevatin 2 , Robert Norton 1
  1. Pathology Queensland, Townsville, QLD, Australia
  2. Internal Medicine, Townsville University Hospital, Townsville, QLD, Australia

PURPOSE 

Mucormycetes are ubiquitous, fast growing, saprophytic fungi (moulds) characterised by rapidly progressive disease, extensive tissue destruction and angioinvasion. The most frequently reported pathogens causing mucormycosis globally are Rhizopus spp., Mucor spp., and Lichtheimia spp. There is significant geographic variation and thus knowledge of local epidemiology is important [1].

Saksenaea species are commonly associated with cutaneous infections in immunocompetent hosts, particularly following traumatic inoculation. Despite a worldwide distribution, cases have been mostly reported from tropical regions in India and Australia, while cases in Central European climatic conditions are rare [2,3]. 

This retrospective review aimed to describe spectrum of disease, local epidemiology and relative pathogen prevalence in North Queensland as compared to other Australian studies and overseas.

 

MATERIALS AND METHOD

An extended enquiry of the laboratory information system (Auslab) and the local Infectious Diseases consult database was performed to identify proven and probable mucormycotic infections in North Queensland. Isolates fulfilling the EORTC/MSG criteria for proven or probable invasive fungal infection [4], with adequate clinical details, were included for analysis.

 

RESULTS

A total of 32 proven and probable cases of mucormycosis were identified. Most infections (84.4%) involved the skin and soft tissue, largely attributed to antecedent trauma (73.1%) or iatrogenic injury (15.4%). Diabetes was the most frequently reported comorbidity.

Eleven cases of subcutaneous mucormycosis (34.4%) were caused by Saksenaea spp. All patients with documented causation had a history of trauma, and most were immunocompetent.  

  

CONCLUSION

Our results are in keeping with prior literature demonstrating an association between infection with Saksenaea spp., trauma, cutaneous infection and residence in the tropics [5].

Given the higher frequency of infection with Saksenaea spp. than previously described, there is need for further multi-site research across northern Australia and the tropics to determine its true prevalence and pathogenic potential, particularly in setting of active global ecological change.

 

  1. Cornely OA, Alastruey-Izquierdo A, Arenz D et al. Global guidelines for the diagnosis and management of mucormycosis: an initiative of the European Confederation of Medical Mycology in cooperation with the Mycoses Study Group Education and Research Consortium. Lancet Infectious Diseases. 2019;19:e405-421. https://doi.org/10.1016/S1473-3099(19)30312-3
  2. Singh S, Kanaujia R, Kuar M et al. Saksenaea vasiformis infection: Extensive abdominal wall necrotising fasciitis with systematic review and analysis of 65 cases. Mycoses. 2023;66:697-704. https://doi.org/10.1111/myc.13592
  3. Planegger A, Uyulmaz S, Poskevicius A, Zbinden A, Müller NJ, Calcagni M. Cutaneous Invasive Fungal Infections with Saksenaea Species in Immunocompetent Patients in Europe: A Systematic Review and Case Report. Plast Reconstr Surg Glob Open. 2022 Apr 8;10(4):e4230. doi: 10.1097/GOX.0000000000004230.
  4. Donnelly JP, Chen SC-A, Kauffman CA et al. Revision and Update of the Consensus Definitions of Invasive Fungal Disease From the European Organization for Research and Treatment of Cancer and the Mycoses Study Group Education and Research Consortium. Clinical Infectious Diseases. 2020;71(6):1367–1376. https://doi.org/10.1093/cid/ciz1008
  5. Hume A, Heney C. Epidemiology of culture-positive mucormycosis in Queensland: 2013-2018. Pathology. 2020;52(1):S123-S124. https://doi.org/10.1016/j.pathol.2020.01.421