Performance of the T2Candida Panel for the Diagnosis of Intra-abdominal Candidiasis.
ABSTRACT: Performance of T2Candida for detecting intra-abdominal candidiasis (IAC) was assessed in 48 high-risk patients. T2Candida sensitivity/specificity and positive/negative predictive values were 33%/93% and 71%/74%, respectively. IAC was present in 100% of cases with concordant positive T2Candida/1,3-beta-d-glucan and absent in 90% of concordant negative results. Combination T2Candida/1,3-beta-d-glucan may help guide treatment decisions.
Project description:Intra-abdominal candidiasis (IAC) is poorly understood compared to candidemia. We described the clinical characteristics, microbiology, treatment and outcomes of IAC, and identified risk factors for mortality. We performed a retrospective study of adults diagnosed with IAC at our center in 2012-2013. Risk factors for mortality were evaluated using multivariable logistic regression. We identified 163 patients with IAC, compared to 161 with candidemia. Types of IAC were intra-abdominal abscesses (55%), secondary peritonitis (33%), primary peritonitis (5%), infected pancreatic necrosis (5%), and cholecystitis/cholangitis (3%). Eighty-three percent and 66% of secondary peritonitis and abscesses, respectively, stemmed from gastrointestinal (GI) tract sources. C. albicans (56%) and C. glabrata (24%) were the most common species. Bacterial co-infections and candidemia occurred in 67% and 6% of patients, respectively. Seventy-two percent of patients underwent an early source control intervention (within 5 days) and 72% received early antifungal treatment. 100-day mortality was 28%, and highest with primary (88%) or secondary (40%) peritonitis. Younger age, abscesses and early source control were independent predictors of survival. Younger age, abscesses and early antifungal treatment were independently associated with survival for IAC stemming from GI tract sources. Infectious diseases (ID) consultations were obtained in only 48% of patients. Consulted patients were significantly more likely to receive antifungal treatment. IAC is a common disease associated with heterogeneous manifestations, which result in poor outcomes. All patients should undergo source control interventions and receive antifungal treatment promptly. It is important for the ID community to become more engaged in treating IAC.
Project description:The pathogenesis of Candida glabrata infections is poorly understood. We studied the pathogenesis of intra-abdominal candidiasis (IAC) in mice that were infected intraperitoneally with C. glabrata and sterile feces. C. glabrata BG2 (5 × 10(8) CFU) caused a 100% mortality rate. Sublethal inocula of BG2 (1 × 10(8) or 1 × 10(7) CFU) caused peritonitis that progressed to abscesses. Three clinical C. glabrata strains (5 × 10(8) CFU) caused 80 to 100% mortality rates, while a fourth (strain 346) caused a 29% mortality rate. Following sublethal inocula (1 × 10(7) CFU), the intra-abscess burdens of virulent strain 356 were ?1 log greater than those of strain 346. A C. glabrata ?plb1-2 mutant (phospholipase B genes disrupted) killed mice as well as BG2 did. When sublethal inocula were used, however, the ?plb1-2 mutant was associated with more rapid abscess resolution and lower intra-abscess burdens; these findings were reversed by PLB1 and PLB2 reinsertion. The ?plb1-2 mutant was also more susceptible than BG2 to killing by human neutrophils in vitro. BG2 and the ?plb1-2 mutant were indistinguishable during hematogenously disseminated candidiasis. C. albicans SC5314 was more virulent than C. glabrata BG2 during IAC, causing a 100% mortality rate following a challenge with 5 × 10(7) CFU. In contrast, a sublethal inoculum (1 × 10(7) CFU) of BG2 caused less neutrophil infiltration and greater burdens in peritoneal fluid than SC5314 did and abscesses that persisted longer and contained greater burdens. In conclusion, a mouse model of C. glabrata IAC mimics disease in humans and distinguishes the relative virulence of clinical and gene disruption strains. C. glabrata differed from C. albicans during IAC by being less lethal and eliciting dampened neutrophil responses but resulting in more persistent peritonitis and abscesses.
Project description:BACKGROUND:(1,3)-?-D-Glucan has been widely used in clinical practice for the diagnosis of invasive Candida infections. However, such serum biomarker showed potential to guide antimicrobial therapy in order to reduce the duration of empirical antifungal treatment in critically ill septic patients with suspected invasive candidiasis. METHODS:This was a single-centre, randomized, open-label clinical trial in which critically ill patients were enrolled during the admission to the intensive care unit (ICU). All septic patients who presented invasive Candida infection risk factors and for whom an empirical antifungal therapy was commenced were randomly assigned (1:1) in those stopping antifungal therapy if (1,3)-?-D-glucan was negative ((1,3)-?-D-glucan group) or those continuing the antifungal therapy based on clinical rules (control group). Serum 1,3-?-D-glucan was measured at the enrolment and every 48/72?h over 14?days afterwards. The primary endpoint was the duration of antifungal treatment in the first 30?days after enrolment. RESULTS:We randomized 108 patients into the (1,3)-?-D-glucan (n?=?53) and control (n?=?55) groups. Median [IQR] duration of antifungal treatment was 2?days [1-3] in the (1,3)-?-D-glucan group vs. 10?days [6-13] in the control group (between-group absolute difference in means, 6.29?days [95% CI 3.94-8.65], p?<?0.001). Thirty-day mortality was similar (28.3% [(1,3)-?-D-glucan group] vs. 27.3% [control group], p?=?0.92) as well as the overall rate of documented candidiasis (11.3% [(1,3)-?-D-glucan group] vs. 12.7% [control group], p?=?0.94), the length of mechanical ventilation (p?=?0.97) and ICU stay (p?=?0.23). CONCLUSIONS:In critically ill septic patients admitted to the ICU at risk of invasive candidiasis, a (1,3)-?-D-glucan-guided strategy could reduce the duration of empirical antifungal therapy. However, the safety of this algorithm needs to be confirmed in future, multicentre clinical trial with a larger population. TRIAL REGISTRATION:ClinicalTrials.gov, NCT03117439 , retrospectively registered on 18 April 2017.
Project description:The incidence of nosocomial invasive fungal infections involving Candida spp. has increased markedly in recent years in patients undergoing abdominal surgery. This post hoc analysis aimed to determine the efficacy and safety of anidulafungin treatment in patients with intra-abdominal candidiasis (IAC) from five prospective studies (one comparative and four open-label) of adult surgical patients with microbiologically confirmed Candida intra-abdominal infection. Patients received an intravenous (IV) loading dose of anidulafungin 200 mg, followed by a daily 100-mg maintenance dose. Per study protocols, some patients could be switched to an oral azole after ??5 or ??10 days of IV treatment. Antifungal treatment was maintained for ??14 days after the last positive Candida culture and resolution of symptoms. The global response rate (GRR) at the end of IV treatment (EOIVT) was the primary endpoint. GRR at the end of therapy (EOT), all-cause mortality at days 14 and 28, and safety was also evaluated. Seventy-nine patients had IAC from peritoneal fluid or hepatobiliary tract. C. albicans (72.2%) and C. glabrata (32.9%) were the most common pathogens. Overall GRR was 73.4% and 67.1% at EOIVT and EOT, respectively. All-cause mortality was 17.7% at day 14 and 24.1% at day 28 in the modified intent-to-treat population. Anidulafungin was well tolerated in this population, with most adverse events mild or moderate in severity. In these patients with IAC, anidulafungin showed a GRR at EOIVT similar to the anidulafungin registrational trial, and the results of our analysis confirmed the known safety profile of anidulafungin. ClinicalTrials.gov registration number NCT00496197, registered July 3, 2007, https://clinicaltrials.gov/ct2/show/study/NCT00496197 ; ClinicalTrials.gov registration number NCT00548262, registered October 19, 2007, https://clinicaltrials.gov/ct2/show/record/NCT00548262 ; ClinicalTrials.gov registration number NCT00537329, registered September 25, 2007, https://clinicaltrials.gov/ct2/show/record/NCT00537329 ; ClinicalTrials.gov registration number NCT00689338, registered May 29, 2008, https://clinicaltrials.gov/ct2/show/study/NCT00689338 ; ClinicalTrials.gov registration number NCT00805740, registered November 26, 2008, https://clinicaltrials.gov/ct2/show/NCT00805740.
Project description:Patients undergoing emergency gastrointestinal surgery for intra-abdominal infection are at risk of invasive candidiasis (IC) and candidates for preemptive antifungal therapy.This exploratory, randomized, double-blind, placebo-controlled trial assessed a preemptive antifungal approach with micafungin (100 mg/d) in intensive care unit patients requiring surgery for intra-abdominal infection. Coprimary efficacy variables were the incidence of IC and the time from baseline to first IC in the full analysis set; an independent data review board confirmed IC. An exploratory biomarker analysis was performed using logistic regression.The full analysis set comprised 124 placebo- and 117 micafungin-treated patients. The incidence of IC was 8.9% for placebo and 11.1% for micafungin (difference, 2.24%; [95% confidence interval, -5.52 to 10.20]). There was no difference between the arms in median time to IC. The estimated odds ratio showed that patients with a positive (1,3)-?-d-glucan (ßDG) result were 3.66 (95% confidence interval, 1.01-13.29) times more likely to have confirmed IC than those with a negative result.This study was unable to provide evidence that preemptive administration of an echinocandin was effective in preventing IC in high-risk surgical intensive care unit patients with intra-abdominal infections. This may have been because the drug was administered too late to prevent IC coupled with an overall low number of IC events. It does provide some support for using ßDG to identify patients at high risk of IC.NCT01122368.
Project description:Intra-abdominal candidiasis (IAC) is a prominent invasive fungal infection associated with high mortality. Prompt antifungal therapy and source control are crucial for successful treatment. Echinocandin antifungal drugs are first-line agents; however, their clinical effectiveness is highly variable, with known potential for breakthrough resistance, and little is known about drug exposure at the site of infection. Using matrix-assisted desorption ionization mass spectrometry imaging technology, we investigated the spatial and quantitative distribution in tissue lesions for two echinocandin drugs, micafungin and CD101, in a clinically relevant IAC mouse model. Drug accumulation within lesions was observed with both drugs at their humanized therapeutic doses. CD101, but not micafungin, accumulated in lesions at levels above the mutant prevention concentration of the infecting strain. These findings indicate that current echinocandin drugs are limited by penetration at the site of infection and have implications for clinical outcomes and emergence of resistance in patients with IAC.
Project description:The pathogenesis of intra-abdominal candidiasis is poorly understood.Mice were intraperitoneally infected with Candida albicans (1 × 10(6) colony-forming units) and sterile stool. nanoString assays were used to quantitate messenger RNA for 145 C. albicans genes within the peritoneal cavity at 48 hours.Within 6 hours after infection, mice developed peritonitis, characterized by high yeast burdens, neutrophil influx, and a pH of 7.9 within peritoneal fluid. Organ invasion by hyphae and early abscess formation were evident 6 and 24 hours after infection, respectively; abscesses resolved by day 14. nanoString assays revealed adhesion and responses to alkaline pH, osmolarity, and stress as biologic processes activated in the peritoneal cavity. Disruption of the highly-expressed gene RIM101, which encodes an alkaline-regulated transcription factor, did not impact cellular morphology but reduced both C. albicans burden during early peritonitis and C. albicans persistence within abscesses. RIM101 influenced expression of 49 genes during intra-abdominal candidiasis, including previously unidentified Rim101 targets. Overexpression of the RIM101-dependent gene SAP5, which encodes a secreted protease, restored the ability of a rim101 mutant to persist within abscesses.A mouse model of intra-abdominal candidiasis is valuable for studying pathogenesis and C. albicans gene expression. RIM101 contributes to persistence within intra-abdominal abscesses, at least in part through activation of SAP5.
Project description:We studied three clinical isolates of Candida spp. (one C. tropicalis isolate and two C. glabrata isolates) from patients with invasive candidiasis. The first isolate emerged during echinocandin treatment, while the others emerged after the same treatment. These strains harbored an amino acid substitution in Fksp never linked before with reduced echinocandin susceptibility in C. tropicalis or in C. glabrata. The molecular mechanism of reduced susceptibility was confirmed using a 1,3-beta-D-glucan synthase inhibition assay.
Project description:Innate immunity depends upon recognition of surface features common to broad groups of pathogens. The glucose polymer beta-glucan has been implicated in fungal immune recognition. Fungal walls have two kinds of beta-glucan: beta-1,3-glucan and beta-1,6-glucan. Predominance of beta-1,3-glucan has led to the presumption that it is the key immunological determinant for neutrophils. Examining various beta-glucans for their ability to stimulate human neutrophils, we find that the minor cell wall component beta-1,6-glucan mediates neutrophil activity more efficiently than beta-1,3-glucan, as measured by engulfment, production of reactive oxygen species, and expression of heat shock proteins. Neutrophils rapidly ingest beads coated with beta-1,6-glucan while ignoring those coated with beta-1,3-glucan. Complement factors C3b/C3d are deposited on beta-1,6-glucan more readily than on beta-1,3-glucan. Beta-1,6-glucan is also important for efficient engulfment of the human pathogen Candida albicans. These unique stimulatory effects offer potential for directed stimulation of neutrophils in a therapeutic context.
Project description:β-1,3-Glucanase is considered as a useful enzymatic tool for β-1,3-glucan degradation to produce (1→3)-linked β-glucan oligosaccharides with pharmacological activity properties. To validly isolate β-1,3-glucanase-producing microorganisms, the soil of Wolfiporia extensa, considered an environment rich in β-1,3-glucan-degrading microorganisms, was subjected to high throughput sequencing. The results demonstrated that the genera Streptomyces (1.90%) and Arthrobacter (0.78%) belonging to the order Actinomycetales (8.64%) in the phylum Actinobacteria (18.64%) were observed in soil for P. cocos cultivation (FTL?). Actinomycetes were considered as the candidates for isolation of glucan-degrading microorganisms. Out of 58 isolates, only 11 exhibited β-1,3-glucan-degrading activity. The isolate SYBCQL belonging to the genus Kitasatospora with β-1,3-glucan-degrading activity was found and reported for the first time and the isolate SYBC17 displayed the highest yield (1.02 U/mg) among the isolates. To check the β-1,3-glucanase contribution to β-1,3-glucan-degrading activity, two genes, 17-W and 17-Q, encoding β-1,3-glucanase in SYBC17 and one gene QLK1 in SYBCQL were cloned and expressed for verification at the molecular level. Our findings collectively showed that the isolates able to secrete β-1,3-glucanase could be obtained with the assistance of high-throughput sequencing and genes expression analysis. These methods provided technical support for isolating β-1,3-glucanase-producing microorganisms.