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Background An increased incidence of fungal infections caused by Candida species, especially Candida glabrata and Candida krusei, which are less susceptible to azoles, has been observed. Standardized susceptibility testing is essential for clinical management and for monitoring the epidemiology of resistance. Aims We evaluated the performance of two different susceptibility testing commercial methods, Vitek 2® and Sensititre YeastOne®, and compared them with the standard broth microdilution method (CLSI). Methods A total of 80 isolates of several Candida species (Candida albicans, Candida parapsilosis complex, Candida tropicalis, C. glabrata and C. krusei) were selected for this study. Results We analyzed the categorical agreement (CA) between the methods, stratifying the disagreements. The average CA between the methods was 96.3% for Vitek 2® and 84% for Sensititre YeastOne®. No very major errors were observed. Major errors and minor errors were found for all the isolates tested. With the azoles, both Vitek 2® and Sensititre YeastOne® had good and similar performance levels, except for C. tropicalis and C. krusei (Sensititre YeastOne® showed low CA, 56.2%). With the echinocandins, both methods showed good performance for C. albicans, C. parapsilosis and C. tropicalis. However, we observed important discrepancies for C. krusei with caspofungin: Vitek 2® had 100% CA while Sensititre YeastOne® had only 25%. With amphotericin B, both Vitek 2® and Sensititre YeastOne® had good performance with high CA. Conclusions Despite the limited isolates tested, we concluded that both methods have good performance and are reliable for antifungal susceptibility testing. However, caspofungin activity against C. krusei and C. glabrata should be interpreted carefully when using Sensititre YeastOne® because we observed a low CA.

Persistent candidemia refers to the continued isolation of the same Candida species in the blood of a candidemic patient despite appropriate therapy. Despite the clinical importance of persistent candidemia, studies have superficially addressed the biological conditions behind this phenomenon. The aim of this study was to evaluate the correlation between the biofilm-forming ability by Candida bloodstream isolates and the persistence of infection. A total of 55 isolates of Candida were tested and characterized in two groups: (i) group I, which included seven patients with persistent candidemia, and (ii) group II, which included 18 patients with nonpersistent candidemia. Microorganisms were identified at the species level by sequencing the internal transcribed spacer (ITS) region of ribosomal DNA (rDNA). Biofilm quantification was evaluated by the crystal violet staining method and confocal scanning laser microscopy (CSLM). Molecular tests confirmed the identification of Candida albicans (92% group I and 94% group II) and Candida dubliniensis isolates (8% group I and 6% group II). All 55 isolates were able to form biofilms, but a higher biofilm mass was produced by C. albicans/C. dubliniensis strains cultured from the persistent group (P < .05). Our data suggest that Candida sp. biofilm production should be considered a relevant biologic variable in explaining patients who fail to clear a bloodstream infection despite adequate antifungal treatment with triazoles.

IntroductionAcute viral hepatitis is a disease of great clinical importance. This study proposes actions to better characterise cases of acute hepatitis in Brazil and to provide relevant information to institutionalised health policies within the Unified Health System. Available data on acute hepatitis in Brazil need to be re-evaluated regarding the different hepatotropic agent (hepatitis A to E virus) frequencies, as well as other agents that can cause similar clinical conditions, such as Herpes Simplex Virus 1 and 2(HSV1, HSV2), Varicella Zoster Virus (VZV), Cytomegalovirus (CMV), Epstein Barr Virus (EBV), Human Herpes Virus 6 and 7 (HHV6, HHV7), arbovirus (yellow fever, dengue, chikungunya, Zika), parvovirus B19, adenovirus, parechovirus, enterovirus, HIV, leptospirosis, toxoplasmosis and syphilis, in addition to autoimmune hepatitis. In this context, the primary aim of this study is the clinical-epidemiological and molecular characterisation of acute viral hepatitis in Brazilian health services from all geographical regions of the country. The present article describes the study protocol.Methods and analysisThis study will evaluate 2280 patients with symptoms and/or signs suggestive of acute liver disease in Brazilian health institutions in all five geographic Brazilian regions. Demographic, epidemiological and clinical data will be collected, as well as blood samples to be analysed at Hospital Israelita Albert Einstein Clinical Laboratory.Ethics and disseminationEthics approval was obtained at the national research ethics committee (Conselho Nacional de Ética em Pesquisa— CONEP–CAAE 00952818.4.1001.0071) and at all participating sites. Results will be published in journals and presented at scientific meetings.

Background Hemodialysis has been described as an important risk factor for the development of candidemia in patients suffering from chronic renal failure . Aims The aim of this study was to evaluate the epidemiology of candidemia in outpatients with renal replacement therapy (RRT) by hemodialysis where the fungemia clearly represents a healthcare-associated infection. Methods We retrospectively collected clinical and laboratory data from patients undergoing at least 3 months of RRT by hemodialysis who developed candidemia within 48 h of hospital admission. Results We identified 14 patients with candidemia with central venous catheters (CVC) in place for 11–277 days before developing fungemia. Deep-seated infection was documented in 6 out of 14 candidiasis cases (43%), including 5 cases of endocarditis (36%). Conclusions CVC in patients under RRT should be promptly replaced by fistulas and grafts to avoid bloodstream infections. Facing a case of candidemia, adequate source control and prompt initiation of antifungal therapy are mandatory to avoid morbidity and mortality.

Candida parapsilosis is the main non- albicans Candida species isolated from patients in Latin America. Mutations in the ERG11 gene and overexpression of membrane transporter proteins have been linked to fluconazole resistance. The aim of this study was to evaluate the molecular mechanisms in fluconazole-resistant strains of C. parapsilosis isolated from critically ill patients. The identities of the nine collected C. parapsilosis isolates at the species level were confirmed through molecular identification with a TaqMan qPCR assay. The clonal origin of the strains was checked by microsatellite typing. The Galleria mellonella infection model was used to confirm in vitro resistance. We assessed the presence of ERG11 mutations, as well as the expression of ERG11 and two additional genes that contribute to antifungal resistance ( CDR1 and MDR1 ), by using real-time quantitative PCR. All of the C. parapsilosis ( sensu stricto ) isolates tested exhibited fluconazole MICs between 8 and 16 μg/ml. The in vitro data were confirmed by the failure of fluconazole in the treatment of G. mellonella infected with fluconazole-resistant strains of C. parapsilosis . Sequencing of the ERG11 gene revealed a common mutation leading to a Y132F amino acid substitution in all of the isolates, a finding consistent with their clonal origin. After fluconazole exposure, overexpression was noted for ERG11 , CDR1 , and MDR1 in 9/9, 9/9, and 2/9 strains, respectively. We demonstrated that a combination of molecular mechanisms, including the presence of point mutations in the ERG11 gene, overexpression of ERG11 , and genes encoding efflux pumps, are involved in fluconazole resistance in C. parapsilosis .

An increased incidence of fungal infections caused by Candida species, especially Candida glabrata and Candida krusei, which are less susceptible to azoles, has been observed. Standardized susceptibility testing is essential for clinical management and for monitoring the epidemiology of resistance.We evaluated the performance of two different susceptibility testing commercial methods, Vitek 2A total of 80 isolates of several Candida species (Candida albicans, Candida parapsilosis complex, Candida tropicalis, C. glabrata and C. krusei) were selected for this study.We analyzed the categorical agreement (CA) between the methods, stratifying the disagreements. The average CA between the methods was 96.3% for Vitek 2Despite the limited isolates tested, we concluded that both methods have good performance and are reliable for antifungal susceptibility testing. However, caspofungin activity against C. krusei and C. glabrata should be interpreted carefully when using Sensititre YeastOne

Background Candidemia is an increasing problem in tertiary care hospitals worldwide. Here, we report the first outbreak of candidemia caused by fluconazole-resistant C. parapsilosis (FRCP) strains in Brazil. Methods This was a cross-sectional study of clinical and microbiological data of all candidemic episodes diagnosed from July 2011 to February 2012 in a 200-bed tertiary care hospital. Initial yeast identification and susceptibility testing were performed using the VITEK 2 - System. Isolates of Candida spp. resistant to fluconazole were sent to a reference laboratory (LEMI-UNIFESP) for further molecular identification and confirmation of resistance by CLSI microdilution test. A multivariate analysis was conducted to identify factors associated with FRCP infection. Results We identified a total of 40 critically ill patients with candidemia (15 women) with a median age of 70 years. The incidence of candidemia was 6 cases/1,000 patients admissions, including 28 cases (70 %) of infection with C. parapsilosis, 21 of which (75 %) were resistant to fluconazole. In only 19 % of FRCP candidemia cases had fluconazole been used previously. The results of our study indicated that diabetes is a risk factor for FRCP candidemia (p = 0.002). Overall, mortality from candidemia was 45 %, and mortality from episodes of FRCP infections was 42.9 %. Conclusions The clustering of incident cases in the ICU and molecular typing of strains suggest horizontal transmission of FRCP. Accurate vigilant monitoring for new nosocomial strains of FRCP is required.

Candidemia is a growing problem in hospitals all over the world. Despite advances in the medical support of critically ill patients, candidiasis leads to prolonged hospitalization, and has a crude mortality rate around 50%. We conducted a multicenter surveillance study in 16 hospitals distributed across five regions of Brazil to assess the incidence, species distribution, antifungal susceptibility, and risk factors for bloodstream infections due to Candida species. From June 2007 to March 2010, we studied a total of 2,563 nosocomial bloodstream infection (nBSI) episodes. Candida spp. was the 7th most prevalent agent. Most of the patients were male, with a median age of 56 years. A total of 64 patients (46.7%) were in the ICU when candidemia occurred. Malignancies were the most common underlying condition (32%). The crude mortality rate of candidemia during the hospital admission was 72.2%. Non-albicans species of Candida accounted for 65.7% of the 137 yeast isolates. C. albicans (34.3%), Candida parapsilosis (24.1%), Candida tropicalis (15.3%) and Candida glabrata (10.2%) were the most prevalent species. Only 47 out of 137 Candida isolates were sent to the reference laboratory for antifungal susceptibility testing. All C. albicans, C. tropicalis and C. parapsilosis isolates were susceptible to the 5 antifungal drugs tested. Among 11 C. glabrata isolates, 36% were resistant to fluconazole, and 64% SDD. All of them were susceptible to anidulafungin and amphotericin B. We observed that C. glabrata is emerging as a major player among non-albicans Candida spp. and fluconazole resistance was primarily confined to C. glabrata and C. krusei strains. Candida resistance to echinocandins and amphotericin B remains rare in Brazil. Mortality rates remain increasingly higher than that observed in the Northern Hemisphere countries, emphasizing the need for improving local practices of clinical management of candidemia, including early diagnosis, source control and precise antifungal therapy.