Virulence and resistance factors of Nakaseomyces glabratus (formerly known as Candida glabrata) in Europe: A systematic review

Abstract Background Nakaseomyces glabratus ( N. glabratus ) formerly known as Candida glabrata ( C. glabrata ), is an endogenous opportunistic pathogen, which is generally located in the gastrointestinal tract but can spread in immunocompromised patients. N. glabratus is the second most common pathogen that causes candidemia in several countries. N. glabratus virulence factors may increase antifungal resistance and reduce the number of available treatment options. High resistance to azoles and increasing resistance to echinocandins have been previously reported in N. glabratus . Objective To establish the distribution of N. glabratus isolates in Europe and its drug susceptibility/resistance in each country over the last 7 years. Methods The search was performed across three databases: PubMed, Scopus and Scielo, using the MeSH terms: “ Candida glabrata ”, “ Nakaseomyces glabratus ”, “Europe”, “resistance” and “Epidemiology” exclusively in English. All available information from January 2002 to December 2022 was included, excluding reviews, meta‐analyses and book chapters. Results Fifty‐seven articles with information on antifungal susceptibility in Europe were retrieved and analysed with a total of 15,400 reported C. glabrata isolates. Remarkably, nations that presented the maximum number of cases during the study period included the United Kingdom ( n = 7241, 47.02%), France ( n = 3190, 20.71%), Spain ( n = 900, 5.84%), Hungary ( n = 745, 4.84%) and Italy ( n = 486, 3.16%). C. glabrata isolates presented resistance to azoles [voriconazole ( n = 2225, 14.45%), fluconazole ( n = 1612, 10.47%), itraconazole ( n = 337, 2.19%) and clotrimazole ( n = 89, 0.58%)], increased resistance to echinocandins, especially to anidulafungin ( n = 138, 0.89%), and high sensitivity to amphotericin B. Conclusion The number of candidemia cases associated with triazole‐resistant N. glabratus isolates have been increasing in Europe. Therefore, echinocandins and amphotericin B can be considered optional empirical treatments; however, antifungal susceptibility testing is required to determine the best therapeutic options.