Candida auris: Diagnostic Challenges and Emerging Opportunities for the Clinical Microbiology Laboratory.

Purpose of Review: This review summarises the epidemiology of Candida auris infection and describes contemporary and emerging diagnostic methods for detection and identification of C. auris. Recent Findings: A fifth C. auris clade has been described. Diagnostic accuracy has improved with development of selective/differential media for C. auris. Advances in spectral databases of matrix-associated laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) systems have reduced misidentification. Direct detection of C. auris in clinical specimens using real time PCR is increasingly used, as is whole genome sequencing (WGS) to track nosocomial spread and to study phylogenetic relationships and drug resistance. Summary: C. auris is an important transmissible, nosocomial pathogen. The microbiological laboratory diagnostic capacity has extended beyond culture-based methods to include PCR and WGS. Microbiological techniques on the horizon include the use of MALDI-TOF MS for early echinocandin antifungal susceptibility testing (AST) and expansion of the versatile and information-rich WGS methods for outbreak investigation.

The rise of methicillin resistant Staphylococcus aureus: now the dominant cause of skin and soft tissue infection in Central Australia.

This study aimed to examine the epidemiology and treatment outcomes of community-onset purulent staphylococcal skin and soft tissue infections (SSTI) in Central Australia. We performed a prospective observational study of patients hospitalised with community-onset purulent staphylococcal SSTI (n = 160). Indigenous patients accounted for 78% of cases. Patients were predominantly young adults; however, there were high rates of co-morbid disease. Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) was the dominant phenotype, accounting for 60% of cases. Hospitalisation during the preceding 6 months, and haemodialysis dependence were significant predictors of CA-MRSA infection on univariate analysis. Clinical presentation and treatment outcomes were found to be comparable for methicillin-susceptible S. aureus (MSSA) and methicillin-resistant cases. All MRSA isolates were characterised as non-multi-resistant, with this term used interchangeably with CA-MRSA in this analysis. We did not find an association between receipt of an active antimicrobial agent within the first 48 h, and progression of infection; need for further surgical debridement; unplanned General Practitioner or hospital re-presentation; or need for further antibiotics. At least one adverse outcome was experienced by 39% of patients. Clindamycin resistance was common, while rates of trimethoprim-sulfamethoxazole resistance were low. This study suggested the possibility of healthcare-associated transmission of CA-MRSA. This is the first Australian report of CA-MRSA superseding MSSA as the cause of community onset staphylococcal SSTI.