The laboratory investigation, management, and infection prevention and control of Candida auris: a narrative review to inform the 2024 national guidance update in England

Abstract

The emergent fungal pathogen Candida auris is increasingly recognised as an important cause of healthcare-associated infections globally. It is highly transmissible, adaptable, and persistent, resulting in an organism with significant outbreak potential that risks devastating consequences. Progress in the ability to identify C. auris in clinical specimens is encouraging, but laboratory diagnostic capacity and surveillance systems are lacking in many countries. Intrinsic resistance to commonly used antifungals, combined with the ability to rapidly acquire resistance to therapy, substantially restricts treatment options and novel agents are desperately needed. Despite this, outbreaks can be interrupted, and mortality avoided or minimised, through the application of rigorous infection prevention and control measures with an increasing evidence base. This review provides an update on epidemiology, the impact of the COVID-19 pandemic, risk factors, identification and typing, resistance profiles, treatment, detection of colonisation, and infection prevention and control measures for C. auris. This review has informed a planned 2024 update to the United Kingdom Health Security Agency (UKHSA) guidance on the laboratory investigation, management, and infection prevention and control of Candida auris. A multidisciplinary response is needed to control C. auris transmission in a healthcare setting and should emphasise outbreak preparedness and response, rapid contact tracing and isolation or cohorting of patients and staff, strict hand hygiene and other infection prevention and control measures, dedicated or single-use equipment, appropriate disinfection, and effective communication concerning patient transfers and discharge.

Fig. 1.. Global epidemiology of Candida auris. (a) Countries where C. auris has been reported are presented and categorised by reported association with HCAI outbreaks or evidence of endemicity within a country. (b) Countries where C. auris has been reported are presented according to the year that the first case was detected. Note: there are many countries where C. auris has not yet been reported (white shading); however, this does not mean that it is not present within these countries. Cases of C. auris have been detected and reported in Reunion; however, this is not visible on the maps. Maps were prepared in R (v4.3.1) using the package rworldmap. See Supplementary Material 1 for a full list of countries and references used to produce these maps.

Fig. 2.. (a) Candida auris (clade II) isolate streaked onto a plate of Chromagar Candida Plus with distinctive pale cream colony and diffusing blue halo. (b) Comparative colonial appearances of common species of Candida and allied yeast genera spotted onto Chromagar Candida Plus. Clinical isolates tested were: 1, Nakaseomyces glabratus (ex-Candida glabrata); 2, Saccharomyces cerevisiae; 3, Candida albicans; 4, Candida parapsilosis; 5, Candida auris (clade II); 6, Clavispora lusitaniae (ex-Candida lusitaniae); 7, Meyerozyma guilliermondii (ex-Candida guilliermondii); 8, Trichosporon asahii; 9, Pichia cactophila (ex-Candida inconspicua); 10, Candida auris (clade III); 11, Pichia kudriavzevii (ex-Candida krusei); 12, Meyerozyma caribbica (ex-Candida fermentati); 13, Candida tropicalis; 14, Candida dubliniensis. Plates incubated for 36 h at 35 °C. Image provided by Andrew M. Borman.